Four factors driving 2023’s extreme heat and climate disasters
- July 29, 2023
- Posted by: OptimizeIAS Team
- Category: DPN Topics
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Four factors driving 2023’s extreme heat and climate disasters
Subject : Environment
Section: Climate Change
Context:
- A recent study determined that the weeks long heat wave in Texas and Mexico that started in June 2023 would have been virtually impossible without Human-caused global warming.
- Details:
Human activities that release greenhouse gas emissions into the atmosphere have been increasing temperatures gradually, at an average of 0.2 degrees Fahrenheit (0.1 Celsius) per decade. - Three additional natural factors are also helping drive up global temperatures and fuel disasters this year:
- El Niño,
- Solar fluctuations and
- A massive underwater volcanic eruption.
How is El-Nino involved?
- El Niño is a climate phenomenon that occurs every few years when surface water in the tropical Pacific reverses direction and heats up. That warms the atmosphere above, which influences temperatures and weather patterns around the globe.
- The atmosphere becomes warmer than usual during El-Nino years, that is why 2016 is the warmest year on record.
- A weak El Niño also occurred in 2019-2020, contributing to 2020 becoming the world’s second-warmest year.
- El Niño’s opposite, La Niña, involves cooler-than-usual Pacific currents flowing westward, absorbing heat out of the atmosphere, which cools the globe.
- The world just came out of three straight years of La Niña (2021-2023), meaning we’re experiencing an even greater temperature swing.
- June 2023 was the hottest in modern record. Which is a case of the combined effect of global warming and El-Nino.
Solar Fluctuations:
- The sun’s radiating energy changes over many different time scales known as the solar cycle which is of 11 years.
- Rapid convection within our Sun both generates a strong magnetic field aligned with its spin axis and causes this field to fully flip and reverse every 11 years. This is what causes the 11-year cycle in emitted solar radiation.
- Earth’s temperature increase during a solar maximum, compared with average solar output, is only about 0.09 F (0.05 C), roughly a third of a large El Niño. The opposite happens during a solar minimum.
- The current solar cycle will peak in 2025.
A massive volcanic eruption
- Volcanic eruptions can also significantly affect global climates. They usually do this by lowering global temperatures when erupted sulfate aerosols shield and block a portion of incoming sunlight – but not always.
- The largest volcanic eruption of the 21st century so far, the 2022 eruption of Tonga’s Hunga Tonga-Hunga Ha’apai is having a warming and not cooling effect.
- The eruption released an unusually small amount of cooling sulfate aerosols but an enormous amount of water vapor.
- The molten magma exploded underwater, vaporising a huge volume of ocean water that erupted like a geyser high into the atmosphere.
- Water vapor is a powerful greenhouse gas, and the eruption may end up warming Earth’s surface by about 0.06 F (0.035 C).
Underlying it all: Global warming
- All of this comes on top of anthropogenic, or human-caused, global warming.
- Humans have increased the amount of carbon dioxide in the atmosphere by 50%, primarily through combustion of fossil fuels in vehicles and power plants.