Update app.py

app.py

@@ -214,29 +214,37 @@ with c2:
     </div>
     """, unsafe_allow_html=True)
 
-# 2. Charts
+    # 2. Charts
+st.subheader("US Emissions Trajectory vs. AI Impact")
 
-years = [2015, 2020, 2023]
-emissions_hist = [6600, 6000, 6200] 
-target_2030 = 7200 * 0.50 
-bau_2030 = 6200 
+# Updated Data from Our World in Data (Billion tCO2e -> Million tCO2e)
+years = [2020, 2021, 2022, 2023, 2024]
+emissions_hist = [4690, 5020, 5060, 4920, 4900] 
+
+# Target: 50% reduction from 2005 levels (approx 6130 MMT CO2 in 2005 -> ~3065 MMT target)
+# Adjusted to match the specific CO2-only metric provided
+target_2030 = 3065 
+bau_2030 = 4800 # Optimistic business-as-usual decline for CO2 only
 
 fig1 = go.Figure()
 
+# History Line
 fig1.add_trace(go.Scatter(
     x=years, y=emissions_hist, 
     mode='lines+markers', 
-    name='Historical Emissions', 
+    name='Historical CO₂ (Fossil/Industry)', 
     line=dict(color='gray', width=2)
 ))
 
+# Target Dot (Changed from line to single marker)
 fig1.add_trace(go.Scatter(
-    x=[2023, 2030], y=[6200, target_2030], 
-    mode='lines', 
+    x=[2030], y=[target_2030], 
+    mode='markers', 
     name='2030 Climate Goal (50% Cut)', 
-    line=dict(color='green', dash='dash', width=2)
+    marker=dict(color='green', size=12, symbol='circle')
 ))
 
+# AI Impact Stacked Bar
 fig1.add_trace(go.Bar(
     x=[2030], y=[bau_2030], 
     name='2030 Baseline Estimate', 
@@ -251,16 +259,16 @@ fig1.add_trace(go.Bar(
 
 fig1.update_layout(
     height=650,
-    font=dict(size=18), # Scales all text globally
+    font=dict(size=18), 
     title={
-        'text': "US Emissions Trajectory vs. AI Impact",
-        'font': {'size': 30},
+        'text': "Can we hit the 50% reduction target?",
+        'font': {'size': 24},
         'x': 0.5,
         'xanchor': 'center'
     },
     yaxis={
         'title': {
-            'text': "Emissions (Million tCO<sub>2</sub>e)",
+            'text': "Emissions (Million tCO<sub>2</sub>)",
             'font': {'size': 20}
         },
         'tickfont': {'size': 16}
@@ -286,8 +294,9 @@ st.markdown("---")
 with st.expander("📚 Data Sources & Methodology"):
     st.markdown(f"""
     **Methodology Updates:**
-    * **2030 Baseline Emissions:** Assumes 2023 emissions stay static, {US_BASELINE_MMT} Million tCO2e (EPA Gross GHG Inventory).
+    * **Historical Data:** US Annual CO₂ emissions from fossil fuels and industry (2020-2024). Land-use change emissions are not included. [Source: Our World in Data](https://ourworldindata.org/profile/co2/united-states).
+    * **Baseline Emissions:** Compared against approx. {US_BASELINE_MMT} MMT (EPA Gross GHG Inventory).
     * **Efficiency Logic:** Emissions Factor is calculated dynamically based on the **Electrical Efficiency** slider ({turbine_eff_percent}% currently selected).
         * *Formula:* `EF = (Benchmark Carbon Content) / Efficiency %`
-        * *Benchmark:* Based on standard [NREL](https://docs.nrel.gov/docs/fy21osti/80580.pdf) life cycle emissions data for Combined Cycle Gas Turbines (486 gCO2e/kWh @ 60% efficiency).
+        * Based on standard [NREL](https://docs.nrel.gov/docs/fy21osti/80580.pdf) life cycle emissions data for Combined Cycle Gas Turbines (486 gCO₂e/kWh @ 60% efficiency).
     """)