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The first direct elections for native Kenyans to the Legislative Council took place in 1957. Despite British hopes of handing power to "moderate" local rivals, it was the Kenya African National Union (KANU) of Jomo Kenyatta that formed a government. The Colony of Kenya and the Protectorate of Kenya each came to an end on 12 December 1963 with independence being conferred on all of Kenya. The United Kingdom ceded sovereignty over the Colony of Kenya and, under an agreement dated 8 October 1963, the Sultan of Zanzibar agreed that simultaneous with independence for the Colony of Kenya, the Sultan would cease to have sovereignty over the Protectorate of Kenya so that all of Kenya would be one sovereign, independent state. In this way, Kenya became an independent country under the Kenya Independence Act 1963 of the United Kingdom. Exactly 12 months later on 12 December 1964, Kenya became a republic under the name "Republic of Kenya".
The election held in 1988 saw the advent of the mlolongo (queuing) system, where voters were supposed to line up behind their favoured candidates instead of a secret ballot. This was seen as the climax of a very undemocratic regime and it led to widespread agitation for constitutional reform. Several contentious clauses, including one that allowed for only one political party were changed in the following years. In democratic, multiparty elections in 1992 and 1997, Daniel arap Moi won re-election.
Kenya is a presidential representative democratic republic. The President is both the head of state and head of government, and of a multi-party system. Executive power is exercised by the government. Legislative power is vested in both the government and the National Assembly and the Senate. The Judiciary is independent of the executive and the legislature. There was growing concern especially during former president Daniel arap Moi's tenure that the executive was increasingly meddling with the affairs of the judiciary.[citation needed]
Kenya ranks low on Transparency International's Corruption Perception Index (CPI), a metric which attempts to gauge the prevalence of public sector corruption in various countries. In 2012, the nation placed 139th out of 176 total countries in the CPI, with a score of 27/100. However, there are several rather significant developments with regards to curbing corruption from the Kenyan government, for instance, the establishment of a new and independent Ethics and Anti-Corruption Commission (EACC).
In the Presidential elections, President Kibaki under the Party of National Unity ran for re-election against the main opposition party, the Orange Democratic Movement (ODM). The elections were seen to have been flawed with international observers saying that they were below international standards. After a split which took a crucial 8% of the votes away from the ODM to the newly formed Orange Democratic Movement-Kenya (ODM-K)'s candidate, Kalonzo Musyoka, the race tightened between ODM candidate Raila Odinga and Kibaki. As the count came into the Electoral Commission of Kenya (ECK) headquarters, Odinga was shown to have a slight, and then substantial lead as the results from his strongholds came in early. As the ECK continued to count the votes, Kibaki closed the gap and then overtook his opponent by a substantial margin after votes from his stronghold arrived later. This led to protests and open discrediting of the ECK for complicity and to Odinga declaring himself the "people's president" and calling for a recount.
Since the election riots, the government and civil society organisations started programmes to avoid similar disasters in the future, said Agnes R. M. Aboum – executive director of TAABCO Research and Development Consultants in Nairobi – in the magazine D+C Development and Cooperation. For example, the Truth, Justice and Reconciliation Commission initiated community dialogues, the Evangelical Lutheran Church in Kenya started peace meetings and the Kenya National Dialogue and Reconciliation process was started.
On 28 February 2008, Kibaki and Odinga signed an agreement on the formation of a coalition government in which Odinga would become Kenya's second Prime Minister. Under the deal, the president would appoint cabinet ministers from both PNU and ODM camps depending on each party's strength in Parliament. The agreement stipulated that the cabinet would include a vice-president and two deputy Prime Ministers. After debates, it was passed by Parliament, the coalition would hold until the end of the current Parliament or if either of the parties withdraws from the deal before then.
The new office of the PM will have power and authority to co-ordinate and supervise the functions of the Government and will be occupied by an elected MP who will be the leader of the party or coalition with majority members in Parliament. The world watched Annan and his UN-backed panel and African Union chairman Jakaya Kikwete as they brought together the former rivals to the signing ceremony, beamed live on national TV from the steps of Nairobi's Harambee House. On 29 February 2008, representatives of PNU and ODM began working on the finer details of the power-sharing agreement. Kenyan lawmakers unanimously approved a power-sharing deal 18 March 2008, aimed at salvaging a country usually seen as one of the most stable and prosperous in Africa. The deal brought Kibaki's PNU and Odinga's ODM together and heralded the formation of the grand coalition, in which the two political parties would share power equally.
A constitutional change was considered that would eliminate the position of Prime Minister and simultaneously reduce the powers of the President. A referendum to vote on the proposed constitution was held on 4 August 2010, and the new constitution passed by a wide margin. Among other things, the new constitution delegates more power to local governments and gives Kenyans a bill of rights. It was promulgated on 27 August 2010 at a euphoric ceremony in Nairobi's Uhuru Park, accompanied by a 21-gun salute. The event was attended by various African leaders and praised by the international community. As of that day, the new constitution heralding the Second Republic came into force.
In December 2014, President Uhuru Kenyatta signed a Security Laws Amendment Bill, which supporters of the law suggested was necessary to guard against armed groups. Opposition politicians, human rights groups, and nine Western countries criticised the security bill, arguing that it infringed on democratic freedoms. The governments of the United States, Britain, Germany and France also collectively issued a press statement cautioning about the law's potential impact. Through the Jubillee Coalition, the Bill was later passed on 19 December in the National Assembly under acrimonious circumstances.
With International Criminal Court trial dates in 2013 for both President Kenyatta and Deputy President William Ruto related to the 2007 election aftermath, US President Barack Obama chose not to visit the country during his mid-2013 African trip. Later in the summer, Kenyatta visited China at the invitation of President Xi Jinping after a stop in Russia and not having visited the United States as president. In July 2015 Obama visited Kenya, as the first American president to visit the country while in office.
The armed forces are regularly deployed in peacekeeping missions around the world. Further, in the aftermath of the national elections of December 2007 and the violence that subsequently engulfed the country, a commission of inquiry, the Waki Commission, commended its readiness and adjudged it to "have performed its duty well." Nevertheless, there have been serious allegations of human rights violations, most recently while conducting counter-insurgency operations in the Mt Elgon area and also in the district of Mandera central.
Kenya’s armed forces, like many government institutions in the country, have been tainted by corruption allegations. Because the operations of the armed forces have been traditionally cloaked by the ubiquitous blanket of “state security”, the corruption has been less in public view, and thus less subject to public scrutiny and notoriety. This has changed recently. In what are by Kenyan standards unprecedented revelations, in 2010, credible claims of corruption were made with regard to recruitment and procurement of Armoured Personnel Carriers. Further, the wisdom and prudence of certain decisions of procurement have been publicly questioned.
Although Kenya is the biggest and most advanced economy in east and central Africa, and has an affluent urban minority, it has a Human Development Index (HDI) of 0.519, ranked 145 out of 186 in the world. As of 2005, 17.7% of Kenyans lived on less than $1.25 a day. The important agricultural sector is one of the least developed and largely inefficient, employing 75% of the workforce compared to less than 3% in the food secure developed countries. Kenya is usually classified as a frontier market or occasionally an emerging market, but it is not one of the least developed countries.
East and Central Africa's biggest economy has posted tremendous growth in the service sector, boosted by rapid expansion in telecommunication and financial activity over the last decade, and now[when?] contributes 62% of GDP. 22% of GDP still comes from the unreliable agricultural sector which employs 75% of the labour force (a consistent characteristic of under-developed economies that have not attained food security – an important catalyst of economic growth) A small portion of the population relies on food aid.[citation needed] Industry and manufacturing is the smallest sector, accounting for 16% of GDP. The service, industry and manufacturing sectors only employ 25% of the labour force but contribute 75% of GDP.
Kenya's services sector, which contributes 61% of GDP, is dominated by tourism. The tourism sector has exhibited steady growth in most years since independence and by the late 1980s had become the country's principal source of foreign exchange. Tourists, the largest number being from Germany and the United Kingdom, are attracted mainly to the coastal beaches and the game reserves, notably, the expansive East and West Tsavo National Park 20,808 square kilometres (8,034 sq mi) in the southeast. Tourism has seen a substantial revival over the past several years and is the major contributor to the pick-up in the country's economic growth. Tourism is now Kenya's largest foreign exchange earning sector, followed by flowers, tea, and coffee. In 2006 tourism generated US$803 million, up from US$699 million the previous year. Presently, there are also numerous Shopping Malls in Kenya. In addition, there are four main hypermarket chains in Kenya.
Agriculture is the second largest contributor to Kenya's gross domestic product (GDP), after the service sector. In 2005 agriculture, including forestry and fishing, accounted for 24% of GDP, as well as for 18% of wage employment and 50% of revenue from exports. The principal cash crops are tea, horticultural produce, and coffee. Horticultural produce and tea are the main growth sectors and the two most valuable of all of Kenya's exports. The production of major food staples such as corn is subject to sharp weather-related fluctuations. Production downturns periodically necessitate food aid—for example, in 2004 aid for 1.8 million people because of one of Kenya's intermittent droughts.[citation needed]
A consortium led by the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) has had some success in helping farmers grow new pigeon pea varieties, instead of maize, in particularly dry areas. Pigeon peas are very drought resistant, so can be grown in areas with less than 650 mm annual rainfall. Successive projects encouraged the commercialisation of legumes, by stimulating the growth of local seed production and agro-dealer networks for distribution and marketing. This work, which included linking producers to wholesalers, helped to increase local producer prices by 20–25% in Nairobi and Mombasa. The commercialisation of the pigeon pea is now enabling some farmers to buy assets, ranging from mobile phones to productive land and livestock, and is opening pathways for them to move out of poverty.
Tea, coffee, sisal, pyrethrum, corn, and wheat are grown in the fertile highlands, one of the most successful agricultural production regions in Africa. Livestock predominates in the semi-arid savanna to the north and east. Coconuts, pineapples, cashew nuts, cotton, sugarcane, sisal, and corn are grown in the lower-lying areas. Unfortunately, the country has not attained the level of investment and efficiency in agriculture that can guarantee food security and coupled with resulting poverty (53% of the population lives below the poverty line), a significant portion of the population regularly starves and is heavily dependent on food aid. Poor roads, an inadequate railway network, under-used water transport and expensive air transport have isolated mostly arid and semi-arid areas and farmers in other regions often leave food to rot in the fields because they cannot access markets. This was last seen in August and September 2011 prompting the Kenyans for Kenya initiative by the Red Cross.
Although Kenya is the most industrially developed country in the African Great Lakes region, manufacturing still accounts for only 14% of the GDP. Industrial activity, concentrated around the three largest urban centres, Nairobi, Mombasa and Kisumu, is dominated by food-processing industries such as grain milling, beer production, and sugarcane crushing, and the fabrication of consumer goods, e.g., vehicles from kits. There is a cement production industry.[citation needed] Kenya has an oil refinery that processes imported crude petroleum into petroleum products, mainly for the domestic market. In addition, a substantial and expanding informal sector commonly referred to as Jua Kali engages in small-scale manufacturing of household goods, motor-vehicle parts, and farm implements.[citation needed]
Kenya's inclusion among the beneficiaries of the US Government's African Growth and Opportunity Act (AGOA) has given a boost to manufacturing in recent years. Since AGOA took effect in 2000, Kenya's clothing sales to the United States increased from US$44 million to US$270 million (2006).[citation needed] Other initiatives to strengthen manufacturing have been the new government's favourable tax measures, including the removal of duty on capital equipment and other raw materials.[citation needed]
The largest share of Kenya's electricity supply comes from hydroelectric stations at dams along the upper Tana River, as well as the Turkwel Gorge Dam in the west. A petroleum-fired plant on the coast, geothermal facilities at Olkaria (near Nairobi), and electricity imported from Uganda make up the rest of the supply. Kenya's installed capacity stood at 1,142 megawatts between 2001 and 2003. The state-owned Kenya Electricity Generating Company (KenGen), established in 1997 under the name of Kenya Power Company, handles the generation of electricity, while Kenya Power handles the electricity transmission and distribution system in the country. Shortfalls of electricity occur periodically, when drought reduces water flow. To become energy sufficient, Kenya aims to build a nuclear power plant by 2017.
Kenya has proven deposits of oil in Turkana and the commercial viability was just discovered. Tullow Oil estimates Kenya's oil reserves to be around 10 billion barrels. Exploration is still continuing to determine if there are more reserves. Kenya currently imports all crude petroleum requirements. Kenya, east Africa's largest economy, has no strategic reserves and relies solely on oil marketers' 21-day oil reserves required under industry regulations. Petroleum accounts for 20% to 25% of the national import bill.
Published comments on Kenya's Capital FM website by Liu Guangyuan, China's ambassador to Kenya, at the time of President Kenyatta's 2013 trip to Beijing, said, "Chinese investment in Kenya ... reached $474 million, representing Kenya's largest source of foreign direct investment, and ... bilateral trade ... reached $2.84 billion" in 2012. Kenyatta was "[a]ccompanied by 60 Kenyan business people [and hoped to] ... gain support from China for a planned $2.5 billion railway from the southern Kenyan port of Mombasa to neighboring Uganda, as well as a nearly $1.8 billion dam", according to a statement from the president's office also at the time of the trip. Base Titanium, a subsidiary of Base resources of Australia, shipped its first major consignment of minerals to China. About 25,000 tonnes of ilmenite was flagged off the Kenyan coastal town of Kilifi. The first shipment was expected to earn Kenya about Shs15 – Shs20 Billion in earnings. China has been causing environmental and social problems that include the recent suspension of the railway project.
In 2007, the Kenyan government unveiled Vision 2030, an economic development programme it hopes will put the country in the same league as the Asian Economic Tigers by the year 2030. In 2013, it launched a National Climate Change Action Plan, having acknowledged that omitting climate as a key development issue in Vision 2030 was an oversight. The 200-page Action Plan, developed with support from the Climate & Development Knowledge Network, sets out the Government of Kenya's vision for a 'low carbon climate resilient development pathway'. At the launch in March 2013, the Secretary of the Ministry of Planning, National Development and Vision 2030 emphasised that climate will be a central issue in the renewed Medium Term Plan that will be launched in the coming months. This will create a direct and robust delivery framework for the Action Plan and ensure climate change is treated as an economy-wide issue.
Child labour is common in Kenya. Most working children are active in agriculture. In 2006, UNICEF estimated that up to 30% of girls in the coastal areas of Malindi, Mombasa, Kilifi, and Diani were subject to prostitution. Most of the prostitutes in Kenya are aged 9–18. The Ministry of Gender and Child Affairs employed 400 child protection officers in 2009. The causes of child labour include poverty, the lack of access to education and weak government institutions. Kenya has ratified Convention No. 81 on labour inspection in industries and Convention No. 129 on labour inspection in agriculture.
Kenya's various ethnic groups typically speak their mother tongues within their own communities. The two official languages, English and Swahili, are used in varying degrees of fluency for communication with other populations. English is widely spoken in commerce, schooling and government. Peri-urban and rural dwellers are less multilingual, with many in rural areas speaking only their native languages. British English is primarily used in the country. Additionally, a distinct local dialect, Kenyan English, is used by some communities and individuals in the country, and contains features unique to it that were derived from local Bantu languages, such as Swahili and Kikuyu. It has been developing since colonisation and also contains certain elements of American English. Sheng is a Swahili-based cant spoken in some urban areas. Primarily consisting of a mixture of Swahili and English, it is an example of linguistic code-switching.
The vast majority of Kenyans are Christian (83%), with 47.7% regarding themselves as Protestant and 23.5% as Roman Catholic of the Latin Rite. The Presbyterian Church of East Africa has 3 million followers in Kenya and the surrounding countries. There are smaller conservative Reformed churches, the Africa Evangelical Presbyterian Church, the Independent Presbyterian Church in Kenya, and the Reformed Church of East Africa. 621,200 of Kenyans are Orthodox Christians. Notably, Kenya has the highest number of Quakers in the world, with around 133,000 members. The only Jewish synagogue in the country is located in the capital, Nairobi.
Sizeable minorities of other faiths do exist (Muslim 11.2%, indigenous beliefs 1.7%), and nonreligious 2.4%. Sixty percent of the Muslim population lives in Kenya's Coastal Region, comprising 50% of the total population there. Roughly 4% of Muslims are Ahmadiyya, 8% Shia and another 8% are non-denominational Muslims, while 73% are Sunni. Western areas of the Coast Region are mostly Christian. The upper part of Kenya's Eastern Region is home to 10% of the country's Muslims, where they constitute the majority religious group. In addition, there is a large Hindu population in Kenya (around 300,000), who have played a key role in the local economy; they are mostly of Indian origin.
Nurses treat 80% of the population who visit dispensaries, health centres and private clinics in rural and under-served urban areas. Complicated cases are referred to clinical officers, medical officers and medical practitioners. According to the Kenya National Bureau of Statistics, in 2011 there were 65,000 qualified nurses registered in the country; 8,600 clinical officers and 7,000 doctors for the population of 43 million people (These figures from official registers include those who have died or left the profession hence the actual number of these workers may be lower).
Diseases of poverty directly correlate with a country's economic performance and wealth distribution: Half of Kenyans live below the poverty level. Preventable diseases like malaria, HIV/AIDS, pneumonia, diarrhoea and malnutrition are the biggest burden, major child-killers, and responsible for much morbidity; weak policies, corruption, inadequate health workers, weak management and poor leadership in the public health sector are largely to blame. According to 2009 estimates, HIV prevalence is about 6.3% of the adult population. However, the 2011 UNAIDS Report suggests that the HIV epidemic may be improving in Kenya, as HIV prevalence is declining among young people (ages 15–24) and pregnant women. Kenya had an estimated 15 million cases of malaria in 2006.
Kenya's first system of education was introduced by British colonists. After Kenya's independence on 12 December 1963, an authority named the Ominde Commission was formed to introduce changes that would reflect the nation's sovereignty. The commission focused on identity and unity, which were critical issues at the time. Changes in the subject content of history and geography were made to reflect national cohesion. Between 1964 and 1985, the 7–4–2–3 system was adopted – seven years of primary, four years of lower secondary, two years of upper secondary, and three years of university. All schools had a common curriculum.
In 1981, the Presidential Working Party on the Second University was commissioned to look at both the possibilities of setting up a second university in Kenya as well as the reforming of the entire education system. The committee recommended that the 7–4–2–3 system be changed to an 8–4–4 system (eight years in primary, four years in secondary, and four years in university education). The table under Present-day education in Kenya below shows the structure of the 8–4–4 system. Although the 7–4–2–3 system theoretically ended with the introduction of the new 8–4–4 system in 1985, the last batch of students from the former system graduated from Kenyan Universities in 1992.
The current 8–4–4 system was launched in January 1985. It put more emphasis on vocational subjects on the assumption that the new structure would enable school drop-outs at all levels either to be self-employed or to secure employment in the informal sector. In January 2003, the Government of Kenya announced the introduction of free primary education. As a result, primary school enrolment increased by about 70%. Secondary and tertiary education enrolment has not increased proportionally because payment is still required for attendance. In 2007 the government issued a statement declaring that from 2008, secondary education would be heavily subsidiszed, with the government footing all tuition fees.
Basic formal education starts at age six years and lasts 12 years comprising eight years in primary school and four years in high school or secondary school. Primary school is free in public schools and those who exit at this level can join a vocational youth/village polytechnic or make their own arrangements for an apprenticeship program and learn a trade such as tailoring, carpentry, motor vehicle repair, brick-laying and masonry for about two years. Those who complete high school can join a polytechnic or other technical college and study for three years or proceed directly to the university and study for four years. Graduates from the polytechnics and colleges can then join the workforce and later obtain a specialised higher diploma qualification after a further one to two years of training, or join the university – usually in the second or third year of their respective course. The higher diploma is accepted by many employers in place of a bachelor's degree and direct or accelerated admission to post-graduate studies is possible in some universities.
The country's literacy level stands at 85% of the whole population. Preschool, which targets children from age three to five, is an integral component of the education system and is a key requirement for admission to Standard One (First Grade). At the end of primary education, pupils sit the Kenya Certificate of Primary Education (KCPE), which determines those who proceed to secondary school or vocational training. The result of this examination is needed for placement at secondary school. Primary school age is 6/7-13/14 years. For those who proceed to secondary level, there is a national examination at the end of Form Four – the Kenya Certificate of Secondary Education (KCSE), which determines those proceeding to the universities, other professional training or employment. Students sit examinations in eight subjects of their choosing. However, English, Kiswahili (languages) and mathematics are compulsory subjects.
Other than the curriculum led learning, there are also National and Public Library Services led by the Kenya National Library Service (KNLS). KNLS is the body mandated to establish, equip, manage and maintain national and public libraries in the country. In addition, some of the counties within the country have either established or taken over libraries within their regions. Nairobi County operates four libraries within their network, which included the McMillan Memorial Library located at the central business district of Nairobi. A public library is seen as a peoples university since it is open to all irrespective of age, literacy level and has materials relevant to people of all walks of life.
Kenya is active in several sports, among them cricket, rallying, football, rugby union and boxing. The country is known chiefly for its dominance in middle-distance and long-distance athletics, having consistently produced Olympic and Commonwealth Games champions in various distance events, especially in 800 m, 1,500 m, 3,000 m steeplechase, 5,000 m, 10,000 m and the marathon. Kenyan athletes (particularly Kalenjin) continue to dominate the world of distance running, although competition from Morocco and Ethiopia has reduced this supremacy. Kenya's best-known athletes included the four-time women's Boston Marathon winner and two-time world champion Catherine Ndereba, 800m world record holder David Rudisha, former Marathon world record-holder Paul Tergat, and John Ngugi.
Kenya won several medals during the Beijing Olympics, six gold, four silver and four bronze, making it Africa's most successful nation in the 2008 Olympics. New athletes gained attention, such as Pamela Jelimo, the women's 800m gold medalist who went ahead to win the IAAF Golden League jackpot, and Samuel Wanjiru who won the men's marathon. Retired Olympic and Commonwealth Games champion Kipchoge Keino helped usher in Kenya's ongoing distance dynasty in the 1970s and was followed by Commonwealth Champion Henry Rono's spectacular string of world record performances. Lately, there has been controversy in Kenyan athletics circles, with the defection of a number of Kenyan athletes to represent other countries, chiefly Bahrain and Qatar. The Kenyan Ministry of Sports has tried to stop the defections, but they have continued anyway, with Bernard Lagat the latest, choosing to represent the United States. Most of these defections occur because of economic or financial factors. Some elite Kenyan runners who cannot qualify for their country's strong national team find it easier to qualify by running for other countries.[citation needed]
Kenya has been a dominant force in women's volleyball within Africa, with both the clubs and the national team winning various continental championships in the past decade.[citation needed] The women's team has competed at the Olympics and World Championships but without any notable success. Cricket is another popular and the most successful team sport. Kenya has competed in the Cricket World Cup since 1996. They upset some of the World's best teams and reached semi-finals of the 2003 tournament. They won the inaugural World Cricket League Division 1 hosted in Nairobi and participated in the World T20. Their current captain is Rakep Patel. They participated in the ICC Cricket World Cup 2011. Kenya is represented by Lucas Onyango as a professional rugby league player who plays with Oldham Roughyeds. Besides the former European Super League team, he has played for Widnes Vikings and rugby union with Sale Sharks. Rugby union is increasing in popularity, especially with the annual Safari Sevens tournament. Kenya sevens team ranked 9th in IRB Sevens World Series for the 2006 season. Kenya was also a regional powerhouse in soccer. However, its dominance has been eroded by wrangles within the now defunct Kenya Football Federation, leading to a suspension by FIFA which was lifted in March 2007.
In the motor rallying arena, Kenya is home to the world famous Safari Rally, commonly acknowledged as one of the toughest rallies in the world. It was a part of the World Rally Championship for many years until its exclusion after the 2002 event owing to financial difficulties. Some of the best rally drivers in the world have taken part in and won the rally, such as Björn Waldegård, Hannu Mikkola, Tommi Mäkinen, Shekhar Mehta, Carlos Sainz and Colin McRae. Although the rally still runs annually as part of the Africa rally championship, the organisers are hoping to be allowed to rejoin the World Rally championship in the next couple of years.
Kenyans generally have three meals in a day – breakfast in the morning (kiamsha kinywa), lunch in the afternoon (chakula cha mchana) and supper in the evening (chakula cha jioni or known simply as "chajio"). In between, they have the 10 o'clock tea (chai ya saa nne) and 4 pm tea (chai ya saa kumi). Breakfast is usually tea or porridge with bread, chapati, mahamri, boiled sweet potatoes or yams. Ugali with vegetables, sour milk, meat, fish or any other stew is generally eaten by much of the population for lunch or supper. Regional variations and dishes also exist.
The Intergovernmental Panel on Climate Change (IPCC) is a scientific intergovernmental body under the auspices of the United Nations, set up at the request of member governments. It was first established in 1988 by two United Nations organizations, the World Meteorological Organization (WMO) and the United Nations Environment Programme (UNEP), and later endorsed by the United Nations General Assembly through Resolution 43/53. Membership of the IPCC is open to all members of the WMO and UNEP. The IPCC produces reports that support the United Nations Framework Convention on Climate Change (UNFCCC), which is the main international treaty on climate change. The ultimate objective of the UNFCCC is to "stabilize greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous anthropogenic [i.e., human-induced] interference with the climate system". IPCC reports cover "the scientific, technical and socio-economic information relevant to understanding the scientific basis of risk of human-induced climate change, its potential impacts and options for adaptation and mitigation."
Korean economist Hoesung Lee is the chair of the IPCC since October 8, 2015, following the election of the new IPCC Bureau. Before this election, the IPCC was led by his vice-Chair Ismail El Gizouli, who was designated acting Chair after the resignation of Rajendra K. Pachauri in February 2015. The previous chairs were Rajendra K. Pachauri, elected in May 2002; Robert Watson in 1997; and Bert Bolin in 1988. The chair is assisted by an elected bureau including vice-chairs, working group co-chairs, and a secretariat.
The IPCC Panel is composed of representatives appointed by governments and organizations. Participation of delegates with appropriate expertise is encouraged. Plenary sessions of the IPCC and IPCC Working groups are held at the level of government representatives. Non Governmental and Intergovernmental Organizations may be allowed to attend as observers. Sessions of the IPCC Bureau, workshops, expert and lead authors meetings are by invitation only. Attendance at the 2003 meeting included 350 government officials and climate change experts. After the opening ceremonies, closed plenary sessions were held. The meeting report states there were 322 persons in attendance at Sessions with about seven-eighths of participants being from governmental organizations.
The IPCC receives funding through the IPCC Trust Fund, established in 1989 by the United Nations Environment Programme (UNEP) and the World Meteorological Organization (WMO), Costs of the Secretary and of housing the secretariat are provided by the WMO, while UNEP meets the cost of the Depute Secretary. Annual cash contributions to the Trust Fund are made by the WMO, by UNEP, and by IPCC Members; the scale of payments is determined by the IPCC Panel, which is also responsible for considering and adopting by consensus the annual budget. The organisation is required to comply with the Financial Regulations and Rules of the WMO.
The IPCC does not carry out research nor does it monitor climate related data. Lead authors of IPCC reports assess the available information about climate change based on published sources. According to IPCC guidelines, authors should give priority to peer-reviewed sources. Authors may refer to non-peer-reviewed sources (the "grey literature"), provided that they are of sufficient quality. Examples of non-peer-reviewed sources include model results, reports from government agencies and non-governmental organizations, and industry journals. Each subsequent IPCC report notes areas where the science has improved since the previous report and also notes areas where further research is required.
Each chapter has a number of authors who are responsible for writing and editing the material. A chapter typically has two "coordinating lead authors", ten to fifteen "lead authors", and a somewhat larger number of "contributing authors". The coordinating lead authors are responsible for assembling the contributions of the other authors, ensuring that they meet stylistic and formatting requirements, and reporting to the Working Group chairs. Lead authors are responsible for writing sections of chapters. Contributing authors prepare text, graphs or data for inclusion by the lead authors.
The executive summary of the WG I Summary for Policymakers report says they are certain that emissions resulting from human activities are substantially increasing the atmospheric concentrations of the greenhouse gases, resulting on average in an additional warming of the Earth's surface. They calculate with confidence that CO2 has been responsible for over half the enhanced greenhouse effect. They predict that under a "business as usual" (BAU) scenario, global mean temperature will increase by about 0.3 °C per decade during the [21st] century. They judge that global mean surface air temperature has increased by 0.3 to 0.6 °C over the last 100 years, broadly consistent with prediction of climate models, but also of the same magnitude as natural climate variability. The unequivocal detection of the enhanced greenhouse effect is not likely for a decade or more.
In 2001, 16 national science academies issued a joint statement on climate change. The joint statement was made by the Australian Academy of Science, the Royal Flemish Academy of Belgium for Science and the Arts, the Brazilian Academy of Sciences, the Royal Society of Canada, the Caribbean Academy of Sciences, the Chinese Academy of Sciences, the French Academy of Sciences, the German Academy of Natural Scientists Leopoldina, the Indian National Science Academy, the Indonesian Academy of Sciences, the Royal Irish Academy, Accademia Nazionale dei Lincei (Italy), the Academy of Sciences Malaysia, the Academy Council of the Royal Society of New Zealand, the Royal Swedish Academy of Sciences, and the Royal Society (UK). The statement, also published as an editorial in the journal Science, stated "we support the [TAR's] conclusion that it is at least 90% certain that temperatures will continue to rise, with average global surface temperature projected to increase by between 1.4 and 5.8 °C above 1990 levels by 2100". The TAR has also been endorsed by the Canadian Foundation for Climate and Atmospheric Sciences, Canadian Meteorological and Oceanographic Society, and European Geosciences Union (refer to "Endorsements of the IPCC").
IPCC author Richard Lindzen has made a number of criticisms of the TAR. Among his criticisms, Lindzen has stated that the WGI Summary for Policymakers (SPM) does not faithfully summarize the full WGI report. For example, Lindzen states that the SPM understates the uncertainty associated with climate models. John Houghton, who was a co-chair of TAR WGI, has responded to Lindzen's criticisms of the SPM. Houghton has stressed that the SPM is agreed upon by delegates from many of the world's governments, and that any changes to the SPM must be supported by scientific evidence.
In addition to climate assessment reports, the IPCC is publishing Special Reports on specific topics. The preparation and approval process for all IPCC Special Reports follows the same procedures as for IPCC Assessment Reports. In the year 2011 two IPCC Special Report were finalized, the Special Report on Renewable Energy Sources and Climate Change Mitigation (SRREN) and the Special Report on Managing Risks of Extreme Events and Disasters to Advance Climate Change Adaptation (SREX). Both Special Reports were requested by governments.
The IPCC concentrates its activities on the tasks allotted to it by the relevant WMO Executive Council and UNEP Governing Council resolutions and decisions as well as on actions in support of the UNFCCC process. While the preparation of the assessment reports is a major IPCC function, it also supports other activities, such as the Data Distribution Centre and the National Greenhouse Gas Inventories Programme, required under the UNFCCC. This involves publishing default emission factors, which are factors used to derive emissions estimates based on the levels of fuel consumption, industrial production and so on.
This projection was not included in the final summary for policymakers. The IPCC has since acknowledged that the date is incorrect, while reaffirming that the conclusion in the final summary was robust. They expressed regret for "the poor application of well-established IPCC procedures in this instance". The date of 2035 has been correctly quoted by the IPCC from the WWF report, which has misquoted its own source, an ICSI report "Variations of Snow and Ice in the past and at present on a Global and Regional Scale".
Former IPCC chairman Robert Watson has said "The mistakes all appear to have gone in the direction of making it seem like climate change is more serious by overstating the impact. That is worrying. The IPCC needs to look at this trend in the errors and ask why it happened". Martin Parry, a climate expert who had been co-chair of the IPCC working group II, said that "What began with a single unfortunate error over Himalayan glaciers has become a clamour without substance" and the IPCC had investigated the other alleged mistakes, which were "generally unfounded and also marginal to the assessment".
The third assessment report (TAR) prominently featured a graph labeled "Millennial Northern Hemisphere temperature reconstruction" based on a 1999 paper by Michael E. Mann, Raymond S. Bradley and Malcolm K. Hughes (MBH99), which has been referred to as the "hockey stick graph". This graph extended the similar graph in Figure 3.20 from the IPCC Second Assessment Report of 1995, and differed from a schematic in the first assessment report that lacked temperature units, but appeared to depict larger global temperature variations over the past 1000 years, and higher temperatures during the Medieval Warm Period than the mid 20th century. The schematic was not an actual plot of data, and was based on a diagram of temperatures in central England, with temperatures increased on the basis of documentary evidence of Medieval vineyards in England. Even with this increase, the maximum it showed for the Medieval Warm Period did not reach temperatures recorded in central England in 2007. The MBH99 finding was supported by cited reconstructions by Jones et al. 1998, Pollack, Huang & Shen 1998, Crowley & Lowery 2000 and Briffa 2000, using differing data and methods. The Jones et al. and Briffa reconstructions were overlaid with the MBH99 reconstruction in Figure 2.21 of the IPCC report.
These studies were widely presented as demonstrating that the current warming period is exceptional in comparison to temperatures between 1000 and 1900, and the MBH99 based graph featured in publicity. Even at the draft stage, this finding was disputed by contrarians: in May 2000 Fred Singer's Science and Environmental Policy Project held a press event on Capitol Hill, Washington, D.C., featuring comments on the graph Wibjörn Karlén and Singer argued against the graph at a United States Senate Committee on Commerce, Science and Transportation hearing on 18 July 2000. Contrarian John Lawrence Daly featured a modified version of the IPCC 1990 schematic, which he mis-identified as appearing in the IPCC 1995 report, and argued that "Overturning its own previous view in the 1995 report, the IPCC presented the 'Hockey Stick' as the new orthodoxy with hardly an apology or explanation for the abrupt U-turn since its 1995 report". Criticism of the MBH99 reconstruction in a review paper, which was quickly discredited in the Soon and Baliunas controversy, was picked up by the Bush administration, and a Senate speech by US Republican senator James Inhofe alleged that "manmade global warming is the greatest hoax ever perpetrated on the American people". The data and methodology used to produce the "hockey stick graph" was criticized in papers by Stephen McIntyre and Ross McKitrick, and in turn the criticisms in these papers were examined by other studies and comprehensively refuted by Wahl & Ammann 2007, which showed errors in the methods used by McIntyre and McKitrick.
On 23 June 2005, Rep. Joe Barton, chairman of the House Committee on Energy and Commerce wrote joint letters with Ed Whitfield, Chairman of the Subcommittee on Oversight and Investigations demanding full records on climate research, as well as personal information about their finances and careers, from Mann, Bradley and Hughes. Sherwood Boehlert, chairman of the House Science Committee, said this was a "misguided and illegitimate investigation" apparently aimed at intimidating scientists, and at his request the U.S. National Academy of Sciences arranged for its National Research Council to set up a special investigation. The National Research Council's report agreed that there were some statistical failings, but these had little effect on the graph, which was generally correct. In a 2006 letter to Nature, Mann, Bradley, and Hughes pointed out that their original article had said that "more widespread high-resolution data are needed before more confident conclusions can be reached" and that the uncertainties were "the point of the article".
The IPCC Fourth Assessment Report (AR4) published in 2007 featured a graph showing 12 proxy based temperature reconstructions, including the three highlighted in the 2001 Third Assessment Report (TAR); Mann, Bradley & Hughes 1999 as before, Jones et al. 1998 and Briffa 2000 had both been calibrated by newer studies. In addition, analysis of the Medieval Warm Period cited reconstructions by Crowley & Lowery 2000 (as cited in the TAR) and Osborn & Briffa 2006. Ten of these 14 reconstructions covered 1,000 years or longer. Most reconstructions shared some data series, particularly tree ring data, but newer reconstructions used additional data and covered a wider area, using a variety of statistical methods. The section discussed the divergence problem affecting certain tree ring data.
On 1 February 2007, the eve of the publication of IPCC's major report on climate, a study was published suggesting that temperatures and sea levels have been rising at or above the maximum rates proposed during the last IPCC report in 2001. The study compared IPCC 2001 projections on temperature and sea level change with observations. Over the six years studied, the actual temperature rise was near the top end of the range given by IPCC's 2001 projection, and the actual sea level rise was above the top of the range of the IPCC projection.
Another example of scientific research which suggests that previous estimates by the IPCC, far from overstating dangers and risks, have actually understated them is a study on projected rises in sea levels. When the researchers' analysis was "applied to the possible scenarios outlined by the Intergovernmental Panel on Climate Change (IPCC), the researchers found that in 2100 sea levels would be 0.5–1.4 m [50–140 cm] above 1990 levels. These values are much greater than the 9–88 cm as projected by the IPCC itself in its Third Assessment Report, published in 2001". This may have been due, in part, to the expanding human understanding of climate.
Michael Oppenheimer, a long-time participant in the IPCC and coordinating lead author of the Fifth Assessment Report conceded in Science Magazine's State of the Planet 2008-2009 some limitations of the IPCC consensus approach and asks for concurring, smaller assessments of special problems instead of the large scale approach as in the previous IPCC assessment reports. It has become more important to provide a broader exploration of uncertainties. Others see as well mixed blessings of the drive for consensus within the IPCC process and ask to include dissenting or minority positions or to improve statements about uncertainties.
The IPCC process on climate change and its efficiency and success has been compared with dealings with other environmental challenges (compare Ozone depletion and global warming). In case of the Ozone depletion global regulation based on the Montreal Protocol has been successful, in case of Climate Change, the Kyoto Protocol failed. The Ozone case was used to assess the efficiency of the IPCC process. The lockstep situation of the IPCC is having built a broad science consensus while states and governments still follow different, if not opposing goals. The underlying linear model of policy-making of more knowledge we have, the better the political response will be is being doubted.
According to Sheldon Ungar's comparison with global warming, the actors in the ozone depletion case had a better understanding of scientific ignorance and uncertainties. The ozone case communicated to lay persons "with easy-to-understand bridging metaphors derived from the popular culture" and related to "immediate risks with everyday relevance", while the public opinion on climate change sees no imminent danger. The stepwise mitigation of the ozone layer challenge was based as well on successfully reducing regional burden sharing conflicts. In case of the IPCC conclusions and the failure of the Kyoto Protocol, varying regional cost-benefit analysis and burden-sharing conflicts with regard to the distribution of emission reductions remain an unsolved problem. In the UK, a report for a House of Lords committee asked to urge the IPCC to involve better assessments of costs and benefits of climate change but the Stern Review ordered by the UK government made a stronger argument in favor to combat human-made climate change.
Since the IPCC does not carry out its own research, it operates on the basis of scientific papers and independently documented results from other scientific bodies, and its schedule for producing reports requires a deadline for submissions prior to the report's final release. In principle, this means that any significant new evidence or events that change our understanding of climate science between this deadline and publication of an IPCC report cannot be included. In an area of science where our scientific understanding is rapidly changing, this has been raised as a serious shortcoming in a body which is widely regarded as the ultimate authority on the science. However, there has generally been a steady evolution of key findings and levels of scientific confidence from one assessment report to the next.[citation needed]
In February 2010, in response to controversies regarding claims in the Fourth Assessment Report, five climate scientists – all contributing or lead IPCC report authors – wrote in the journal Nature calling for changes to the IPCC. They suggested a range of new organizational options, from tightening the selection of lead authors and contributors, to dumping it in favor of a small permanent body, or even turning the whole climate science assessment process into a moderated "living" Wikipedia-IPCC. Other recommendations included that the panel employ a full-time staff and remove government oversight from its processes to avoid political interference.
Chloroplasts' main role is to conduct photosynthesis, where the photosynthetic pigment chlorophyll captures the energy from sunlight and converts it and stores it in the energy-storage molecules ATP and NADPH while freeing oxygen from water. They then use the ATP and NADPH to make organic molecules from carbon dioxide in a process known as the Calvin cycle. Chloroplasts carry out a number of other functions, including fatty acid synthesis, much amino acid synthesis, and the immune response in plants. The number of chloroplasts per cell varies from 1 in algae up to 100 in plants like Arabidopsis and wheat.
Chloroplasts are highly dynamic—they circulate and are moved around within plant cells, and occasionally pinch in two to reproduce. Their behavior is strongly influenced by environmental factors like light color and intensity. Chloroplasts, like mitochondria, contain their own DNA, which is thought to be inherited from their ancestor—a photosynthetic cyanobacterium that was engulfed by an early eukaryotic cell. Chloroplasts cannot be made by the plant cell and must be inherited by each daughter cell during cell division.
Chloroplasts are one of many types of organelles in the plant cell. They are considered to have originated from cyanobacteria through endosymbiosis—when a eukaryotic cell engulfed a photosynthesizing cyanobacterium that became a permanent resident in the cell. Mitochondria are thought to have come from a similar event, where an aerobic prokaryote was engulfed. This origin of chloroplasts was first suggested by the Russian biologist Konstantin Mereschkowski in 1905 after Andreas Schimper observed in 1883 that chloroplasts closely resemble cyanobacteria. Chloroplasts are only found in plants and algae.
Cyanobacteria are considered the ancestors of chloroplasts. They are sometimes called blue-green algae even though they are prokaryotes. They are a diverse phylum of bacteria capable of carrying out photosynthesis, and are gram-negative, meaning that they have two cell membranes. Cyanobacteria also contain a peptidoglycan cell wall, which is thicker than in other gram-negative bacteria, and which is located between their two cell membranes. Like chloroplasts, they have thylakoids within. On the thylakoid membranes are photosynthetic pigments, including chlorophyll a. Phycobilins are also common cyanobacterial pigments, usually organized into hemispherical phycobilisomes attached to the outside of the thylakoid membranes (phycobilins are not shared with all chloroplasts though).
Somewhere around a billion years ago, a free-living cyanobacterium entered an early eukaryotic cell, either as food or as an internal parasite, but managed to escape the phagocytic vacuole it was contained in. The two innermost lipid-bilayer membranes that surround all chloroplasts correspond to the outer and inner membranes of the ancestral cyanobacterium's gram negative cell wall, and not the phagosomal membrane from the host, which was probably lost. The new cellular resident quickly became an advantage, providing food for the eukaryotic host, which allowed it to live within it. Over time, the cyanobacterium was assimilated, and many of its genes were lost or transferred to the nucleus of the host. Some of its proteins were then synthesized in the cytoplasm of the host cell, and imported back into the chloroplast (formerly the cyanobacterium).
These chloroplasts, which can be traced back directly to a cyanobacterial ancestor, are known as primary plastids ("plastid" in this context means almost the same thing as chloroplast). All primary chloroplasts belong to one of three chloroplast lineages—the glaucophyte chloroplast lineage, the rhodophyte, or red algal chloroplast lineage, or the chloroplastidan, or green chloroplast lineage. The second two are the largest, and the green chloroplast lineage is the one that contains the land plants.
The alga Cyanophora, a glaucophyte, is thought to be one of the first organisms to contain a chloroplast. The glaucophyte chloroplast group is the smallest of the three primary chloroplast lineages, being found in only 13 species, and is thought to be the one that branched off the earliest. Glaucophytes have chloroplasts that retain a peptidoglycan wall between their double membranes, like their cyanobacterial parent. For this reason, glaucophyte chloroplasts are also known as muroplasts. Glaucophyte chloroplasts also contain concentric unstacked thylakoids, which surround a carboxysome - an icosahedral structure that glaucophyte chloroplasts and cyanobacteria keep their carbon fixation enzyme rubisco in. The starch that they synthesize collects outside the chloroplast. Like cyanobacteria, glaucophyte chloroplast thylakoids are studded with light collecting structures called phycobilisomes. For these reasons, glaucophyte chloroplasts are considered a primitive intermediate between cyanobacteria and the more evolved chloroplasts in red algae and plants.
Rhodoplasts have a double membrane with an intermembrane space and phycobilin pigments organized into phycobilisomes on the thylakoid membranes, preventing their thylakoids from stacking. Some contain pyrenoids. Rhodoplasts have chlorophyll a and phycobilins for photosynthetic pigments; the phycobilin phycoerytherin is responsible for giving many red algae their distinctive red color. However, since they also contain the blue-green chlorophyll a and other pigments, many are reddish to purple from the combination. The red phycoerytherin pigment is an adaptation to help red algae catch more sunlight in deep water—as such, some red algae that live in shallow water have less phycoerytherin in their rhodoplasts, and can appear more greenish. Rhodoplasts synthesize a form of starch called floridean, which collects into granules outside the rhodoplast, in the cytoplasm of the red alga.
The chloroplastidan chloroplasts, or green chloroplasts, are another large, highly diverse primary chloroplast lineage. Their host organisms are commonly known as the green algae and land plants. They differ from glaucophyte and red algal chloroplasts in that they have lost their phycobilisomes, and contain chlorophyll b instead. Most green chloroplasts are (obviously) green, though some aren't, like some forms of Hæmatococcus pluvialis, due to accessory pigments that override the chlorophylls' green colors. Chloroplastidan chloroplasts have lost the peptidoglycan wall between their double membrane, and have replaced it with an intermembrane space. Some plants seem to have kept the genes for the synthesis of the peptidoglycan layer, though they've been repurposed for use in chloroplast division instead.
While primary chloroplasts have a double membrane from their cyanobacterial ancestor, secondary chloroplasts have additional membranes outside of the original two, as a result of the secondary endosymbiotic event, when a nonphotosynthetic eukaryote engulfed a chloroplast-containing alga but failed to digest it—much like the cyanobacterium at the beginning of this story. The engulfed alga was broken down, leaving only its chloroplast, and sometimes its cell membrane and nucleus, forming a chloroplast with three or four membranes—the two cyanobacterial membranes, sometimes the eaten alga's cell membrane, and the phagosomal vacuole from the host's cell membrane.
Euglenophytes are a group of common flagellated protists that contain chloroplasts derived from a green alga. Euglenophyte chloroplasts have three membranes—it is thought that the membrane of the primary endosymbiont was lost, leaving the cyanobacterial membranes, and the secondary host's phagosomal membrane. Euglenophyte chloroplasts have a pyrenoid and thylakoids stacked in groups of three. Starch is stored in the form of paramylon, which is contained in membrane-bound granules in the cytoplasm of the euglenophyte.
Cryptophytes, or cryptomonads are a group of algae that contain a red-algal derived chloroplast. Cryptophyte chloroplasts contain a nucleomorph that superficially resembles that of the chlorarachniophytes. Cryptophyte chloroplasts have four membranes, the outermost of which is continuous with the rough endoplasmic reticulum. They synthesize ordinary starch, which is stored in granules found in the periplastid space—outside the original double membrane, in the place that corresponds to the red alga's cytoplasm. Inside cryptophyte chloroplasts is a pyrenoid and thylakoids in stacks of two.
Apicomplexans are another group of chromalveolates. Like the helicosproidia, they're parasitic, and have a nonphotosynthetic chloroplast. They were once thought to be related to the helicosproidia, but it is now known that the helicosproida are green algae rather than chromalveolates. The apicomplexans include Plasmodium, the malaria parasite. Many apicomplexans keep a vestigial red algal derived chloroplast called an apicoplast, which they inherited from their ancestors. Other apicomplexans like Cryptosporidium have lost the chloroplast completely. Apicomplexans store their energy in amylopectin starch granules that are located in their cytoplasm, even though they are nonphotosynthetic.
Apicoplasts have lost all photosynthetic function, and contain no photosynthetic pigments or true thylakoids. They are bounded by four membranes, but the membranes are not connected to the endoplasmic reticulum. The fact that apicomplexans still keep their nonphotosynthetic chloroplast around demonstrates how the chloroplast carries out important functions other than photosynthesis. Plant chloroplasts provide plant cells with many important things besides sugar, and apicoplasts are no different—they synthesize fatty acids, isopentenyl pyrophosphate, iron-sulfur clusters, and carry out part of the heme pathway. This makes the apicoplast an attractive target for drugs to cure apicomplexan-related diseases. The most important apicoplast function is isopentenyl pyrophosphate synthesis—in fact, apicomplexans die when something interferes with this apicoplast function, and when apicomplexans are grown in an isopentenyl pyrophosphate-rich medium, they dump the organelle.
The most common dinophyte chloroplast is the peridinin-type chloroplast, characterized by the carotenoid pigment peridinin in their chloroplasts, along with chlorophyll a and chlorophyll c2. Peridinin is not found in any other group of chloroplasts. The peridinin chloroplast is bounded by three membranes (occasionally two), having lost the red algal endosymbiont's original cell membrane. The outermost membrane is not connected to the endoplasmic reticulum. They contain a pyrenoid, and have triplet-stacked thylakoids. Starch is found outside the chloroplast An important feature of these chloroplasts is that their chloroplast DNA is highly reduced and fragmented into many small circles. Most of the genome has migrated to the nucleus, and only critical photosynthesis-related genes remain in the chloroplast.
The fucoxanthin dinophyte lineages (including Karlodinium and Karenia) lost their original red algal derived chloroplast, and replaced it with a new chloroplast derived from a haptophyte endosymbiont. Karlodinium and Karenia probably took up different heterokontophytes. Because the haptophyte chloroplast has four membranes, tertiary endosymbiosis would be expected to create a six membraned chloroplast, adding the haptophyte's cell membrane and the dinophyte's phagosomal vacuole. However, the haptophyte was heavily reduced, stripped of a few membranes and its nucleus, leaving only its chloroplast (with its original double membrane), and possibly one or two additional membranes around it.
Members of the genus Dinophysis have a phycobilin-containing chloroplast taken from a cryptophyte. However, the cryptophyte is not an endosymbiont—only the chloroplast seems to have been taken, and the chloroplast has been stripped of its nucleomorph and outermost two membranes, leaving just a two-membraned chloroplast. Cryptophyte chloroplasts require their nucleomorph to maintain themselves, and Dinophysis species grown in cell culture alone cannot survive, so it is possible (but not confirmed) that the Dinophysis chloroplast is a kleptoplast—if so, Dinophysis chloroplasts wear out and Dinophysis species must continually engulf cryptophytes to obtain new chloroplasts to replace the old ones.
Some dinophytes, like Kryptoperidinium and Durinskia have a diatom (heterokontophyte) derived chloroplast. These chloroplasts are bounded by up to five membranes, (depending on whether you count the entire diatom endosymbiont as the chloroplast, or just the red algal derived chloroplast inside it). The diatom endosymbiont has been reduced relatively little—it still retains its original mitochondria, and has endoplasmic reticulum, ribosomes, a nucleus, and of course, red algal derived chloroplasts—practically a complete cell, all inside the host's endoplasmic reticulum lumen. However the diatom endosymbiont can't store its own food—its starch is found in granules in the dinophyte host's cytoplasm instead. The diatom endosymbiont's nucleus is present, but it probably can't be called a nucleomorph because it shows no sign of genome reduction, and might have even been expanded. Diatoms have been engulfed by dinoflagellates at least three times.
Lepidodinium viride and its close relatives are dinophytes that lost their original peridinin chloroplast and replaced it with a green algal derived chloroplast (more specifically, a prasinophyte). Lepidodinium is the only dinophyte that has a chloroplast that's not from the rhodoplast lineage. The chloroplast is surrounded by two membranes and has no nucleomorph—all the nucleomorph genes have been transferred to the dinophyte nucleus. The endosymbiotic event that led to this chloroplast was serial secondary endosymbiosis rather than tertiary endosymbiosis—the endosymbiont was a green alga containing a primary chloroplast (making a secondary chloroplast).
While most chloroplasts originate from that first set of endosymbiotic events, Paulinella chromatophora is an exception that acquired a photosynthetic cyanobacterial endosymbiont more recently. It is not clear whether that symbiont is closely related to the ancestral chloroplast of other eukaryotes. Being in the early stages of endosymbiosis, Paulinella chromatophora can offer some insights into how chloroplasts evolved. Paulinella cells contain one or two sausage shaped blue-green photosynthesizing structures called chromatophores, descended from the cyanobacterium Synechococcus. Chromatophores cannot survive outside their host. Chromatophore DNA is about a million base pairs long, containing around 850 protein encoding genes—far less than the three million base pair Synechococcus genome, but much larger than the approximately 150,000 base pair genome of the more assimilated chloroplast. Chromatophores have transferred much less of their DNA to the nucleus of their host. About 0.3–0.8% of the nuclear DNA in Paulinella is from the chromatophore, compared with 11–14% from the chloroplast in plants.
Chloroplasts have their own DNA, often abbreviated as ctDNA, or cpDNA. It is also known as the plastome. Its existence was first proved in 1962, and first sequenced in 1986—when two Japanese research teams sequenced the chloroplast DNA of liverwort and tobacco. Since then, hundreds of chloroplast DNAs from various species have been sequenced, but they're mostly those of land plants and green algae—glaucophytes, red algae, and other algal groups are extremely underrepresented, potentially introducing some bias in views of "typical" chloroplast DNA structure and content.
The inverted repeat regions are highly conserved among land plants, and accumulate few mutations. Similar inverted repeats exist in the genomes of cyanobacteria and the other two chloroplast lineages (glaucophyta and rhodophyceæ), suggesting that they predate the chloroplast, though some chloroplast DNAs have since lost or flipped the inverted repeats (making them direct repeats). It is possible that the inverted repeats help stabilize the rest of the chloroplast genome, as chloroplast DNAs which have lost some of the inverted repeat segments tend to get rearranged more.
The mechanism for chloroplast DNA (cpDNA) replication has not been conclusively determined, but two main models have been proposed. Scientists have attempted to observe chloroplast replication via electron microscopy since the 1970s. The results of the microscopy experiments led to the idea that chloroplast DNA replicates using a double displacement loop (D-loop). As the D-loop moves through the circular DNA, it adopts a theta intermediary form, also known as a Cairns replication intermediate, and completes replication with a rolling circle mechanism. Transcription starts at specific points of origin. Multiple replication forks open up, allowing replication machinery to transcribe the DNA. As replication continues, the forks grow and eventually converge. The new cpDNA structures separate, creating daughter cpDNA chromosomes.
In cpDNA, there are several A → G deamination gradients. DNA becomes susceptible to deamination events when it is single stranded. When replication forks form, the strand not being copied is single stranded, and thus at risk for A → G deamination. Therefore, gradients in deamination indicate that replication forks were most likely present and the direction that they initially opened (the highest gradient is most likely nearest the start site because it was single stranded for the longest amount of time). This mechanism is still the leading theory today; however, a second theory suggests that most cpDNA is actually linear and replicates through homologous recombination. It further contends that only a minority of the genetic material is kept in circular chromosomes while the rest is in branched, linear, or other complex structures.
One of competing model for cpDNA replication asserts that most cpDNA is linear and participates in homologous recombination and replication structures similar to bacteriophage T4. It has been established that some plants have linear cpDNA, such as maize, and that more species still contain complex structures that scientists do not yet understand. When the original experiments on cpDNA were performed, scientists did notice linear structures; however, they attributed these linear forms to broken circles. If the branched and complex structures seen in cpDNA experiments are real and not artifacts of concatenated circular DNA or broken circles, then a D-loop mechanism of replication is insufficient to explain how those structures would replicate. At the same time, homologous recombination does not expand the multiple A --> G gradients seen in plastomes. Because of the failure to explain the deamination gradient as well as the numerous plant species that have been shown to have circular cpDNA, the predominant theory continues to hold that most cpDNA is circular and most likely replicates via a D loop mechanism.
Endosymbiotic gene transfer is how we know about the lost chloroplasts in many chromalveolate lineages. Even if a chloroplast is eventually lost, the genes it donated to the former host's nucleus persist, providing evidence for the lost chloroplast's existence. For example, while diatoms (a heterokontophyte) now have a red algal derived chloroplast, the presence of many green algal genes in the diatom nucleus provide evidence that the diatom ancestor (probably the ancestor of all chromalveolates too) had a green algal derived chloroplast at some point, which was subsequently replaced by the red chloroplast.
Curiously, around half of the protein products of transferred genes aren't even targeted back to the chloroplast. Many became exaptations, taking on new functions like participating in cell division, protein routing, and even disease resistance. A few chloroplast genes found new homes in the mitochondrial genome—most became nonfunctional pseudogenes, though a few tRNA genes still work in the mitochondrion. Some transferred chloroplast DNA protein products get directed to the secretory pathway (though it should be noted that many secondary plastids are bounded by an outermost membrane derived from the host's cell membrane, and therefore topologically outside of the cell, because to reach the chloroplast from the cytosol, you have to cross the cell membrane, just like if you were headed for the extracellular space. In those cases, chloroplast-targeted proteins do initially travel along the secretory pathway).
After a chloroplast polypeptide is synthesized on a ribosome in the cytosol, an enzyme specific to chloroplast proteins phosphorylates, or adds a phosphate group to many (but not all) of them in their transit sequences. Phosphorylation helps many proteins bind the polypeptide, keeping it from folding prematurely. This is important because it prevents chloroplast proteins from assuming their active form and carrying out their chloroplast functions in the wrong place—the cytosol. At the same time, they have to keep just enough shape so that they can be recognized by the chloroplast. These proteins also help the polypeptide get imported into the chloroplast.
In land plants, chloroplasts are generally lens-shaped, 5–8 μm in diameter and 1–3 μm thick. Greater diversity in chloroplast shapes exists among the algae, which often contain a single chloroplast that can be shaped like a net (e.g., Oedogonium), a cup (e.g., Chlamydomonas), a ribbon-like spiral around the edges of the cell (e.g., Spirogyra), or slightly twisted bands at the cell edges (e.g., Sirogonium). Some algae have two chloroplasts in each cell; they are star-shaped in Zygnema, or may follow the shape of half the cell in order Desmidiales. In some algae, the chloroplast takes up most of the cell, with pockets for the nucleus and other organelles (for example some species of Chlorella have a cup-shaped chloroplast that occupies much of the cell).
There are some common misconceptions about the outer and inner chloroplast membranes. The fact that chloroplasts are surrounded by a double membrane is often cited as evidence that they are the descendants of endosymbiotic cyanobacteria. This is often interpreted as meaning the outer chloroplast membrane is the product of the host's cell membrane infolding to form a vesicle to surround the ancestral cyanobacterium—which is not true—both chloroplast membranes are homologous to the cyanobacterium's original double membranes.
The chloroplast double membrane is also often compared to the mitochondrial double membrane. This is not a valid comparison—the inner mitochondria membrane is used to run proton pumps and carry out oxidative phosphorylation across to generate ATP energy. The only chloroplast structure that can considered analogous to it is the internal thylakoid system. Even so, in terms of "in-out", the direction of chloroplast H+ ion flow is in the opposite direction compared to oxidative phosphorylation in mitochondria. In addition, in terms of function, the inner chloroplast membrane, which regulates metabolite passage and synthesizes some materials, has no counterpart in the mitochondrion.
The chloroplast membranes sometimes protrude out into the cytoplasm, forming a stromule, or stroma-containing tubule. Stromules are very rare in chloroplasts, and are much more common in other plastids like chromoplasts and amyloplasts in petals and roots, respectively. They may exist to increase the chloroplast's surface area for cross-membrane transport, because they are often branched and tangled with the endoplasmic reticulum. When they were first observed in 1962, some plant biologists dismissed the structures as artifactual, claiming that stromules were just oddly shaped chloroplasts with constricted regions or dividing chloroplasts. However, there is a growing body of evidence that stromules are functional, integral features of plant cell plastids, not merely artifacts.
Some chloroplasts contain a structure called the chloroplast peripheral reticulum. It is often found in the chloroplasts of C4 plants, though it has also been found in some C3 angiosperms, and even some gymnosperms. The chloroplast peripheral reticulum consists of a maze of membranous tubes and vesicles continuous with the inner chloroplast membrane that extends into the internal stromal fluid of the chloroplast. Its purpose is thought to be to increase the chloroplast's surface area for cross-membrane transport between its stroma and the cell cytoplasm. The small vesicles sometimes observed may serve as transport vesicles to shuttle stuff between the thylakoids and intermembrane space.
Chloroplasts have their own ribosomes, which they use to synthesize a small fraction of their proteins. Chloroplast ribosomes are about two-thirds the size of cytoplasmic ribosomes (around 17 nm vs 25 nm). They take mRNAs transcribed from the chloroplast DNA and translate them into protein. While similar to bacterial ribosomes, chloroplast translation is more complex than in bacteria, so chloroplast ribosomes include some chloroplast-unique features. Small subunit ribosomal RNAs in several Chlorophyta and euglenid chloroplasts lack motifs for shine-dalgarno sequence recognition, which is considered essential for translation initiation in most chloroplasts and prokaryotes. Such loss is also rarely observed in other plastids and prokaryotes.

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