Daily Hot Topic
Topic : Northern Hemisphere Summer 2023: Hottest in 2,000 Years (Nature Study)
GS-3 Mains : Environment
Revision Notes
- Cause: Rising greenhouse gas emissions and climate patterns.
- Temperature: 1.19°C warmer than previous record (246 AD, 0.88°C).
- This period (1-500 AD) considered warmest in past 2,000 years (Late Roman Warm Period, natural causes).
- Comparison: Almost 4°C warmer than coldest summer (536 AD, post-volcanic eruption).
- Impact: 2015 Paris Agreement’s 1.5°C warming limit likely exceeded.
- Data Source: Tree ring analysis by researchers from UK, Germany, Czech Republic (past climate over 2,000 years).
- Wider rings indicate warm/wet years, thinner rings indicate cold/dry years.
- Past temperature data helps assess human impact on climate change (natural variability vs. recent trends).
- June-July-August 2023 temperatures 2.07°C warmer than pre-industrial average (1850-1900).
- Southern Hemisphere data limited, so conclusions not possible there.
- El Nino events (warm Pacific Ocean phase) linked to warmer periods in past 2,000 years.
- Central Pacific Nino 3.4 sea surface temperature (SST) used as a reference point.
- El Nino events linked to stronger heatwaves due to global warming.
- Prof. Jan Esper (Johannes Gutenberg University Mainz, Germany) emphasizes human influence on El Nino intensity.
- 2023 heatwave consistent with earlier predictions of extreme summer temperatures.
- May 2024 NOAA forecast: El Nino likely transitions to neutral in June, with a possible La Nina development later (49% chance June-August, 69% chance July-Sept).
Source : https://www.downtoearth.org.in/news/climate-change/northern-hemisphere-2023-summer-warmest-in-two-millennia-study-calls-for-urgent-greenhouse-gas-reduction-96152
हिन्दी