Climate Change
1. What is Climate Change?
- Definition: Long-term alteration in average weather patterns, primarily due to human activities since the Industrial Revolution (≈1750).
- Global Warming vs Climate Change: Global warming = rise in Earth’s average surface temperature; Climate change includes warming plus shifts in precipitation, wind patterns, frequency/severity of extreme events.
2. Causes – Natural & Anthropogenic
| Natural Drivers | Anthropogenic Drivers (Dominant since 1850) |
|---|---|
| Volcanic eruptions, Solar variability, Orbital cycles (Milankovitch) | Fossil-fuel combustion (CO₂ 75% of GHGs), Deforestation, Industrial processes, Agriculture (CH₄, N₂O), F-gases |
3. Key Greenhouse Gases (GHGs)
| Gas | Global Warming Potential (100-yr) | Share in total GHGs (2022) | Main Sources |
|---|---|---|---|
| CO₂ | 1 | 75% | Coal/oil/gas, cement, land-use change |
| CH₄ | 28–34 | 17% | Rice, livestock, oil & gas leaks, landfills |
| N₂O | 265–298 | 6% | Fertilisers, manure, industry |
| F-gases (HFC, PFC, SF₆) | 100–23,500 | 2% | Refrigerants, electronics |
4. Vital Statistics & Figures
- Pre-industrial CO₂: 280 ppm → May 2023 (Mauna Loa): 424 ppm (highest in >4 million yrs).
- Average surface temperature rise: +1.15 ± 0.13 °C (2011-2020 vs 1850-1900) – IPCC AR6.
- IPCC safe limit (Paris Agreement): “well below 2 °C” & pursue 1.5 °C; 1.5 °C likely crossed during 2030-35 at current trajectory.
- Global CO₂-eq emissions 2022: 58 Gt; to stay ≤1.5 °C remaining budget ≈ 400 Gt (8 yrs at today’s rate).
- Sea-level rise rate: 3.7 mm/yr (1993-2020) – nearly 2× that of 1901-1971.
- Arctic sea-ice loss: 13% per decade (1979-2022).
5. Impact Snapshot
| Sector | Key Effects |
|---|---|
| Agriculture | 10-25% yield loss in wheat, maize per +1 °C in tropics |
| Health | 296,000 heat-related deaths/yr (1998-2017, WHO) |
| Biodiversity | 20-30% species at very high extinction risk at +2 °C |
| Economy | Climate disasters cost US$ 313 bn in 2022 (Munich Re) |
6. Important Dates & Events
| Year | Milestone |
|---|---|
| 1988 | IPCC established by WMO & UNEP |
| 1992 | UNFCCC (Rio Earth Summit) – 154 signatories |
| 1997 | Kyoto Protocol (1st binding cuts; adopted COP-3) |
| 2005 | Kyoto Protocol enters into force (16-Feb) |
| 2015 | Paris Agreement (COP-21) – 196 Parties |
| 2018 | IPCC 1.5 °C Special Report |
| 26-31 Oct 2021 | COP-26 (Glasgow) – “Glasgow Climate Pact”, net-zero pledges |
| 6-18 Nov 2022 | COP-27 (Sharm el-Sheikh) – Loss & Damage fund agreed |
7. India-Specific Facts
- India’s rank in 2022 GHG emitters: 3rd (after China, USA) – 7% of global total.
- Per-capita emission: 2.3 t CO₂ (world avg 6.3 t).
- National Action Plan on Climate Change (NAPCC) launched: 30-Jun-2008 (8 missions).
- Intended Nationally Determined Contribution (INDC) targets (2015):
- 40% cumulative electric power from non-fossil by 2030
- 33-35% emission intensity reduction of GDP vs 2005
- Additional 2.5-3 bn t CO₂ eq carbon sink through forest & tree cover
- Net-zero pledge by India: 2070 (announced by PM Modi at COP-26).
- Largest solar park (as of 2023): Bhadla Solar Park, Rajasthan – 2.25 GW.
- First coastal blue-carbon climate project: Sundarbans (Mangrove restoration).
8. Quick-Reference Tables
Table-1: Major Global Climate Reports
| Report | Released by | Latest Edition | Key takeaway |
|---|---|---|---|
| IPCC Assessment Report | IPCC | AR6 (2021-23) | Human influence “unequivocal”; 1.5 °C window narrowing |
| Emissions Gap Report | UNEP | 2022 | Current policies lead to 2.8 °C warming by 2100 |
| Production Gap Report | UNEP | 2021 | Nations plan to produce 110% more fossil fuels than 1.5 °C allows |
| Lancet Countdown | Lancet | 2022 | Climate-related health impacts at record high |
Table-2: India’s Eight National Missions under NAPCC
| Mission | Launch | Aim |
|---|---|---|
| Solar | 2010 | 100 GW solar by 2022 (achieved 63 GW grid-connected by 2022) |
| Enhanced Energy Efficiency | 2010 | Perform-Achieve-Trade (PAT) for industries |
| Sustainable Habitat | 2011 | Promote green buildings, waste-to-energy |
| Water | 2009 | 20% improvement in water-use efficiency |
| Himalayan Eco-system | 2010 | Protect fragile Himalayan biodiversity |
| Green India | 2014 | Increase forest cover 5 m ha, carbon sink 50 m t |
| Sustainable Agriculture | 2011 | Climate-resilient farming practices |
| Strategic Knowledge | 2014 | Climate modelling & data for policy |
9. One-Liner Rapid-Fire Facts
- CO₂ levels today are 50% higher than in 1750.
- 19 of the 20 warmest years on record occurred since 2000.
- Methane’s atmospheric lifetime ≈ 12 yrs, but traps 80× more heat than CO₂ over 20 yrs.
- Arctic warming at ~4× the global average (“Arctic amplification”).
- Coral reefs expected to decline by 70-90% at 1.5 °C warming.
- Every 1 °C rise can cut rice yield by 3-7% in India.
- Oceans absorb ~90% of excess heat & 25% of human CO₂ emissions.
- Climate finance gap for developing nations: US$ 5.8 trillion needed by 2030.
- Kyoto’s 2nd commitment period (Doha Amendment) ended 2020.
- India’s first biennial update report to UNFCCC submitted in 2016.
10. Multiple-Choice Questions (Railway Exam Pattern)
1. Which gas has the highest share in total global greenhouse emissions?
Ans: Carbon dioxide (CO₂)
2. The Paris Agreement was adopted in which year?
Ans: 2015
3. The target of keeping global temperature rise “well below 2 °C” was agreed at:
Ans: COP-21, Paris
4. India’s net-zero emission target year is:
Ans: 2070
5. Which of the following is NOT a mission under India’s NAPCC?
Ans: Wind Mission (no such mission exists)
6. The IPCC was jointly established by:
Ans: WMO and UNEP
7. Current atmospheric CO₂ concentration exceeds:
Ans: 420 ppm
8. Which GHG has the shortest atmospheric lifetime but highest short-term warming potential?
Ans: Methane
9. The Kyoto Protocol entered into force in:
Ans: 2005
10. At COP-27, which new global funding mechanism was agreed?
Ans: Loss and Damage Fund
11. Approximately what percentage of climate-disaster economic losses in 2022 were uninsured?
Ans: 60%
12. Which Indian state hosts the world’s largest single-location solar park as of 2023?
Ans: Rajasthan
13. The global average temperature has risen by how much since pre-industrial times?
Ans: ~1.1 °C
14. Which report series is released by UNEP to highlight the gap between pledges & required emission cuts?
Ans: Emissions Gap Report
15. Sea-level rise is currently occurring at an average rate of roughly:
Ans: 3-4 mm per year
16. What is India’s rank in the 2022 list of absolute global GHG emitters?
Ans: 3rd
17. The “Himalayan Eco-system” mission under NAPCC mainly aims at:
Ans: Protecting Himalayan biodiversity & glacier monitoring
Last-Minute Cheat Sheet
- 1.5 °C = 2030-35 crossing | 2 °C = catastrophic tipping points
- CO₂ 280 → 424 ppm; CH₄ 0.7 → 1.9 ppm; N₂O 270 → 335 ppb
- Kyoto: 1997, 2005; Paris: 2015, 2020 (ratification); Glasgow: COP-26 2021
- India: 100 GW solar (2014-target 2022), 2070 net-zero, 33-35% intensity cut
- Reports: IPCC AR6, UNEP Gap, Lancet Countdown, Production Gap
- Arctic ice ‑13%/decade, sea level +3.7 mm/yr, oceans absorb 90% heat
BETA
