Key Climate Reports: IEA · UNEP · IPCC · CCPI 🌡️
IEA World Energy Outlook 2024 · UNEP Emissions Gap Report 2024 & 2025 · IPCC AR6 Synthesis Report 2023 · CCPI 2025 & 2026 — All old reports replaced with latest editions. Carbon Budget explained simply.
IEA World Energy Outlook 2024 — The Annual Energy Bible
💡 What Is the IEA and Why Does UPSC Care?
The International Energy Agency (IEA) was established in 1974 after the OPEC oil crisis — to ensure energy security for member nations (mostly OECD developed countries). Today it’s the world’s most authoritative energy analyst. Its World Energy Outlook (WEO) — published every October — maps global energy demand, supply, investment, and emissions under multiple scenarios. India is an Association member of the IEA since 2017 (not a full member — IEA membership requires OECD membership). UPSC tests both the content of IEA reports AND knowledge about the IEA itself.
- STEPS (Stated Policies Scenario): What happens if countries implement only their CURRENT stated policies — no new ambition. Energy demand and emissions projections based on today’s reality.
- APS (Announced Pledges Scenario): What if ALL national energy and climate targets and pledges (including net-zero goals) are met in full and on time — gives a “best case with current pledges” picture.
- NZE (Net Zero Emissions by 2050 Scenario): The pathway required to reach net zero by 2050 and limit warming to 1.5°C — maps out what would need to happen. Described as an “increasingly narrow path.”
- Peak emissions approaching: The world is close to peaking CO₂ emissions by around 2025 — but after peaking, emissions would NOT decline substantially under current policies without more government action
- Clean energy surge: More than 560 GW of renewables was added in 2023. Even under current policies, renewables will reach 10,000 GW by 2030 — enough to push power sector emissions into decline.
- Energy security + climate linked: Extreme weather events (intensified by high emissions) are already posing energy security risks. In 2023, ~800 TWh of electricity was used for cooling during extreme heat events (vs <300 TWh in the 1990s)
- Fossil fuel oversupply: WEO 2024 projects an overhang of oil and LNG supply during the second half of the 2020s — a major market shift from scarcity to buyers’ market for fossil fuels. Has implications for India’s energy import costs.
- 750 million without electricity: Mainly in Sub-Saharan Africa. 2 billion without clean cooking. The NZE scenario is the only one providing universal energy access by 2030.
- Geopolitical risks: ~20% of global oil and LNG supplies flow through the Strait of Hormuz — highlighting energy security vulnerabilities. India imports ~85% of its oil needs → vulnerable.
- Electricity demand surge: Data centres, AI, and EV charging are driving new electricity demand peaks — demanding faster grid expansion and storage solutions.
- India in WEO 2024:
- India saw the second-largest absolute energy demand growth in 2024 (after China)
- India’s clean energy investment: US$68 billion in 2023 — up 40% from 2016-20 average. Nearly half in solar PV.
- India’s energy demand growth is on track to outpace all other regions by 2050
- India’s target: Net zero by 2070 | 500 GW non-fossil capacity by 2030 | 50% energy from renewables by 2030
- Clean energy investment needs to rise a further 20% to get India fully on track for its goals
- Established: November 1974 | after OPEC oil embargo (1973)
- Headquarters: Paris, France
- Members: 31 member countries (all OECD members) | 13 association members
- India: Association member since March 2017 (not full member — would require joining OECD first)
- Mission: Energy security, economic development, and clean energy. The “Three Es”: Energy security, Economic growth, Environmental sustainability
- Key publications: World Energy Outlook (annual, October) | World Energy Investment (annual) | Global Energy Review (annual) | Electricity Market Report
- IEA Global Energy Review 2025 (latest): Total energy-related CO₂ hit all-time high of 37.8 Gt CO₂ in 2024. Solar + wind + nuclear deployment prevented 2.6 billion tonnes additional CO₂. India’s energy CO₂ rose 5.3% in 2024 — highest rate among major economies.
UNEP Emissions Gap Report 2024 — “No More Hot Air…Please!”
💡 What Is the “Emissions Gap”? — Think of It as a Budget Shortfall
Every country makes climate pledges called NDCs (Nationally Determined Contributions) — their plan to cut emissions under the Paris Agreement. The UNEP Emissions Gap Report asks: even if all these pledges are actually kept, how much would global temperatures still rise? The “gap” is the difference between where emissions NEED to be (to limit warming to 1.5°C or 2°C) and where they ARE headed under current pledges. Think of it like a household budget: the target says “spend ₹5,000 this month,” but even after all your promised cuts, you’re still spending ₹12,000. The Emissions Gap Report is the annual auditor that measures this shortfall.
Paris Agreement Target
Full NDC Implementation
Only Unconditional NDCs
Current Policies Only
- Report title: “No more hot air…please!” — named to signal frustration that countries keep making pledges without delivering
- The Gap: Nations must cut 42% of global GHG emissions by 2030 and 57% by 2035 vs 2019 levels to stay on a 1.5°C pathway. Current pledges fall dramatically short.
- No G20 country strengthened its 2030 NDC targets (as of 2024 report)
- Carbon budget (remaining, 2024):
- For <2°C warming (66% chance): 900 GtCO₂ remaining
- For <1.5°C warming (50% chance): 200 GtCO₂ remaining
- Good news: Solar, wind, and forests offer real promise for sweeping and fast emissions cuts. 60 countries have 2035 NDC targets in some form. If 60% recycling of e-waste by 2030 etc.
- What’s needed: 6-fold increase in mitigation investment | G20 nations must “do the heavy lifting” | Reform of global financial architecture | Minimum 101 parties (82% of emissions) have adopted net-zero pledges
- India’s NDC (for context): India submitted updated NDC in 2022 — committed to: 500 GW non-fossil capacity by 2030, 50% electricity from renewables by 2030, 45% emissions intensity reduction by 2030 (vs 2005), net zero by 2070
UNEP Emissions Gap Report 2025 — “Off Target” Latest
- Global GHG emissions 2024: Record high of 57.7 GtCO₂e — up 2.6% from 2023. Another year of missed opportunity to peak emissions.
- Temperature under current policies: 2.8°C — slightly better than 2024 report’s 3.1°C, but improvement includes 0.1°C from methodology update, 0.1°C cancelled by US Paris withdrawal
- Temperature under full NDC implementation: 2.3–2.5°C — still far above Paris target
- Temporary 1.5°C overshoot: The multi-decadal temperature average will exceed 1.5°C at least temporarily. Best case: overshoot of ~0.3°C before potentially returning to 1.5°C by 2100 — only if rapid mitigation starts in 2025.
- US withdrawal from Paris Agreement: Will cancel ~0.1°C of progress made elsewhere
- China: EGR 2025 is the first to project China’s emissions may peak in 2025 — followed by a reduction of 0.3–1.4 GtCO₂e by 2030
- Only 1/3 of Paris parties submitted or announced new NDCs by September 2025 cutoff. G20 not collectively on track for even 2030 NDC targets.
- Finance gap: Developing countries estimate needing US$5.3 trillion to meet NDC commitments. Huge gap between ambition and finance available.
- India’s absolute emissions rise: India recorded the highest absolute rise in GHG emissions globally in 2024 (largest volume increase among all countries)
- India’s percentage rise: 3.6% increase in emissions — second highest percentage after Indonesia (4.6%)
- India’s CO₂ from energy (IEA GER 2025): India’s energy-related CO₂ rose 5.3% in 2024 — highest rate among major economies
- But: India’s per capita emissions remain well below the global average — 2.9 tCO₂e vs global average 6.6 tCO₂e (CCPI 2025). India argues this context is crucial — a developing country growing economically.
- India missed NDC deadline: India failed to submit new NDC 3.0 by September 30, 2025 deadline — creating pressure at COP30 in Belém, Brazil
- India’s position: “Climate justice trap” — low per-capita emissions (moral high ground) but rising total emissions. India has consistently argued that developed economies have failed to deliver the promised $100 billion/year climate finance under UNFCCC.
- Six largest emitters in total GHG (2024): China → USA → India → EU → Russia → Indonesia
- Historic cumulative CO₂: USA (largest historically) → China → EU. India much lower historically — the basis of “common but differentiated responsibilities” (CBDR) principle
Climate Change Performance Index (CCPI) — 2025 & 2026
- Full name: Climate Change Performance Index (CCPI)
- Published by: Germanwatch + NewClimate Institute + Climate Action Network (CAN) International — annually since 2005
- Coverage: 63 countries + EU (over 90% of global GHG emissions)
- Four assessment categories: (1) GHG Emissions (40% weight) · (2) Renewable Energy (20%) · (3) Energy Use/Efficiency (20%) · (4) Climate Policy (20%)
- Key quirk: Top 3 spots always remain VACANT — because no country performs well enough across ALL categories to earn a “very high” overall rating. This means rank 4 is effectively #1. This is a favourite UPSC trap!
- Ratings: Very High → High → Medium → Low → Very Low
| Rank | Country | Rating | Note |
|---|---|---|---|
| 1–3 | VACANT | — | No country scored high enough across all 4 categories |
| 4 | 🇩🇰 Denmark | Very High | Top performer — only country to achieve “high” in climate policy. Strong renewable energy, clear national agenda. |
| 5 | 🇳🇱 Netherlands | High | Strong climate policy, though new government raises concerns |
| 6 | 🇬🇧 United Kingdom | High | Coal phase-out, pledge to stop new fossil fuel licenses |
| 7 | 🇵🇭 Philippines | High | Strong renewable push, low per-capita emissions |
| 8 | 🇲🇦 Morocco | High | Leading renewable energy adoption in Africa |
| 9 | 🇳🇴 Norway | High | High EV adoption, renewables-rich electricity |
| 10 | 🇮🇳 India | High | Among only 2 G20 countries rated “high” (UK + India). Per capita 2.9 tCO₂e vs global 6.6. But coal dependency noted. |
| 54 | 🇨🇳 China | Low | Large total emissions, ongoing coal use |
| 64 | 🇺🇸 USA | Very Low | High fossil fuel dependence |
| 65 | 🇸🇦 Saudi Arabia | Very Low | Fossil fuel economy |
| 67 | 🇮🇷 Iran | Very Low | Lowest ranked overall |
- India’s rank: 23rd (down from 10th in CCPI 2025 — a 13-place fall)
- India’s rating: Shifted from “High” to “Medium” performer
- Reasons for India’s fall:
- Rising domestic production and consumption of coal — India is among the biggest producers of oil, gas, and coal worldwide
- India scored medium in GHG emissions, climate policy, and energy use
- India scored low in renewable energy (despite solar surge, coal still dominates the grid)
- India’s failure to submit new NDC 3.0 before COP30 deadline
- Top performers (CCPI 2026): Denmark (4th, 80.52 points) → UK (5th) → Morocco (6th)
- Worst G20 performers: USA, China, Russia, Australia, Japan, Saudi Arabia — all “very low”
- Only UK among G20 received a “high” rating in CCPI 2026
- Top 3 vacant again — no country achieves “very high” across all indicators
- India’s score: 61.31
IPCC AR6 Synthesis Report 2023 — Science’s Verdict on the Climate Crisis
💡 Think of IPCC Like a Doctor Giving Earth’s Diagnosis
The IPCC (Intergovernmental Panel on Climate Change) doesn’t do original research — it reviews and synthesises thousands of existing scientific papers to give the world’s governments the most authoritative, comprehensive picture of climate science. The AR6 Synthesis Report is the “final diagnosis” after 5 years of work by 782 scientists. It has three parts: (1) What has already happened to Earth’s climate (Current Status), (2) What will happen under different emissions scenarios (Future Risks), (3) What we can still do (Near-term Responses). UN Secretary-General António Guterres called it “an atlas of human suffering and a damning indictment of failed climate leadership.”
Physical Science Basis
Impacts, Adaptation & Vulnerability
Mitigation of Climate Change
- 1. Current warming (CONFIRMED): Global mean surface temperature is already 1.1°C above pre-industrial levels (2011-2020 average). Human activities are unequivocally the dominant cause.
- 2. 1.5°C breach timing: Even with strong action, 1.5°C will be reached as early as the early 2030s — possibly temporarily. This will cause significantly worse impacts than current climate.
- 3. Cuts required for 1.5°C:
- Emissions must fall 43% by 2030 (vs 2019 levels)
- Emissions must fall 60% by 2035
- Net zero CO₂ by approximately 2050
- 4. Impacts already worse than expected: About half of global population faces severe water scarcity at least 1 month/year. Climate change has slowed agricultural productivity growth in middle and low latitudes. Crop productivity growth shrank by 1/3 in Africa since 1961.
- 5. Irreversible losses are happening: Some terrestrial, coastal, and oceanic ecosystems, freshwater systems, and cryosphere changes are already irreversible. West Antarctic and Greenland ice sheets could melt almost completely if warming reaches 2–3°C.
- 6. Solar and wind are the heroes: Costs of solar PV fell 85%, wind power 55%, in the decade to 2020. This is why the energy transition has accelerated beyond all expectations.
- 7. The window is closing: IPCC is “strongly convinced” that risks increase with every increment of warming. Every tenth of a degree matters. There is no safe level of global warming.
- 8. Multiple climate tipping points: At 1.5°C: risk of triggering tipping points (Amazon dieback, Arctic permafrost collapse, coral reef die-off) increases substantially.
- 9. Adaptation is happening but insufficient: Adaptation measures at national and local levels are increasing, but are “lagging dangerously behind” relative to what is needed.
- 10. AR7 — Next report: IPCC AR7 cycle expected to conclude around 2028–2030. Will be critical input for the 2035 NDC target period and the second Global Stocktake.
Carbon Budget — The Simplest Explanation for Students
💡 The Carbon Budget = Earth’s CO₂ Credit Card
Imagine Earth’s atmosphere has a credit card limit for CO₂ — once you exceed it, the consequences kick in (in this case: 1.5°C or 2°C warming). The remaining carbon budget is how much CO₂ humanity can still emit before reaching that limit. Every tonne of CO₂ we emit today brings us closer to maxing out the card. Once it’s maxed out, no amount of future “good behaviour” can undo the damage quickly — the warming is baked in for centuries.
The current numbers (EGR 2024): For a 50% chance of staying below 1.5°C — we have only 200 GtCO₂ left. At current emission rates (~40 GtCO₂/year from fossil fuels), that’s gone in about 5 years. For a 66% chance of staying below 2°C: 900 GtCO₂ left — roughly 20+ years at current rates.
- Definition: The total amount of CO₂ that can still be emitted into the atmosphere while keeping global warming below a certain temperature threshold with a given probability
- Expressed as: GtCO₂ (gigatonnes of CO₂) — 1 GtCO₂ = 1 billion tonnes
- Why it works: CO₂ has a nearly linear relationship with global temperature — each additional tonne of CO₂ causes a proportional increment of warming
- Two important numbers (EGR 2024, as of 2024):
- 200 GtCO₂ remaining to have a 50% chance of limiting warming to 1.5°C
- 900 GtCO₂ remaining to have a 66% chance of limiting warming to 2°C
- The carbon budget gets smaller every year: Each year humanity emits ~40+ GtCO₂ from fossil fuels alone. At this rate, the 1.5°C carbon budget runs out within 5 years. This is why urgency is paramount.
- Who “owns” the remaining budget? This is a justice debate. If remaining budget is shared equally per capita, developed countries (who already used their share in industrialisation) have little or no budget left. Developing countries (India, Africa, etc.) have greater claims on the remaining budget — this is the basis of India’s “CBDR + per-capita equity” argument in climate negotiations.
- Carbon budget vs GHG budget: Carbon budget usually refers only to CO₂. Including other GHGs (methane, N₂O) in CO₂-equivalent terms changes the budget size but the concept is the same.
- Cumulative vs annual emissions: Carbon budget is about CUMULATIVE (total over time) emissions, not annual. This is why stopping emissions sooner matters more than stopping them slowly over a longer period.
⭐ Master Cheat Sheet — All 4 Reports at a Glance
- IEA: International Energy Agency | Est. 1974 (post-OPEC crisis) | HQ Paris | India: Association member since 2017 | WEO (annual flagship) | Three scenarios: STEPS / APS / NZE
- IEA WEO 2024: Emissions peak by ~2025 but slow decline after | 560 GW renewables added in 2023 | 750 million without electricity | Oil/LNG market shifting to buyers’ market | Energy security + climate inextricably linked
- IEA GER 2025: Energy CO₂ hit all-time high 37.8 Gt in 2024 | India energy CO₂ rose 5.3% — highest rate among major economies | Solar/wind/nuclear deployment prevented 2.6 Bn tonnes additional CO₂
- UNEP EGR 2024 “No more hot air”: 15th edition | Temperature trajectories: Current policies = 3.1°C | Unconditional NDCs = 2.8°C | Full conditional NDCs = 2.6°C | Target 1.5°C needs 42% cut by 2030, 57% by 2035 | Carbon budget remaining: 200 Gt (1.5°C) | 900 Gt (2°C)
- UNEP EGR 2025 “Off Target”: 16th edition | Released Nov 4, 2025 ahead of COP30 Belém | Global GHG: record 57.7 GtCO₂e | Current policies → 2.8°C | Full NDCs → 2.3-2.5°C | India = highest absolute GHG rise in 2024 | India 2nd in % growth (3.6%, after Indonesia 4.6%) | China may peak 2025 | 1.5°C will be temporarily exceeded | Best case: return to 1.5°C by 2100 with immediate action
- Top 6 GHG emitters (2024): China → USA → India → EU → Russia → Indonesia
- India context: Highest absolute emitter rise 2024 BUT per capita 2.9 tCO₂e vs global 6.6 | Net zero by 2070 | India failed to submit NDC 3.0 before COP30 | Historically low cumulative CO₂
- CCPI basics: By Germanwatch + NewClimate Institute + CAN | Annual since 2005 | 63 countries + EU | 4 criteria: GHG (40%) + Renewables (20%) + Energy use (20%) + Climate policy (20%) | Top 3 ALWAYS VACANT
- CCPI 2025 (Nov 2024): Denmark 4th (top) | Netherlands 5th | UK 6th | India 10th — “High” performer | Only 2 G20 countries “high”: UK + India | China 54th, USA 64th, Iran 67th (last)
- CCPI 2026 (Nov 2025): Denmark 4th | UK 5th | Morocco 6th | India 23rd — down 13 places, “Medium” | Score 61.31 | Reason: coal production/consumption rise | Only UK in G20 gets “high” | Top 3 still vacant
- IPCC AR6 Synthesis Report (March 20, 2023): Final report of AR6 cycle | 782 scientists total (WGI: 234, WGII: 270, WGIII: 278) | Released after 5 years
- AR6 key findings: Current warming = 1.1°C | 1.5°C reached early 2030s | 43% cut needed by 2030, 60% by 2035 (vs 2019) | Solar cost fell 85%, wind 55% in a decade | Some losses already irreversible | ~50% global population faces severe water scarcity 1+ month/year
- AR6 Working Groups: WGI (Physical Science, Aug 2021) | WGII (Impacts, Feb 2022) | WGIII (Mitigation, April 2022) + 3 Special Reports: SR1.5 (2018), SRCCL (2019), SROCC (2019)
- AR7: Expected to conclude 2028-2030 | Will be key input for 2035 NDC cycle and 2nd Global Stocktake
- Carbon Budget (remaining, EGR 2024): 200 GtCO₂ for 1.5°C (50% chance) | 900 GtCO₂ for 2°C (66% chance) | At ~40 GtCO₂/year current pace: 1.5°C budget gone in ~5 years


