Temperature Distribution Anamolies
Issue:
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March 2023 was the second warmest March
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The warmest March occurred in 2016, when the biggest El Niño of the 21st century triggered a ‘mini’ global warming.
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However, the January-to-March average temperature anomaly ranks 2023 as the fourth warmest such period on record.
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The Arabian Sea has also warmed more than expected this March, this can favour a stronger monsoon but may also enhance cyclogenesis (i.e. the birth of cyclonic circulation) over the Arabian Sea.
Why such a high temperature?
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Natural climate variability caused by events like El Niño can temporarily spike temperatures.
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A year is an ‘El Niño year’ if warmer water spreads in a band from west to east over the equatorial Pacific Ocean.
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In a ‘La Niña year’, cooler water spreads east to west in the same region.
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Both phenomena have distinct and significant effects on the global climate.
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(Global mean temperatures themselves represent the increasing amount of additional energy we are trapping in the earth system and preventing its escape to space by, among other things, increasing the atmospheric concentration of heat-trapping greenhouse gases.)
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Global temperature:
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Global warming does not necessarily mean that each month or each year will be warmer than the previous month or the previous year.
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Reason:
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It is due to land-ocean-atmosphere processes that dynamically determine the weather and climate
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Some of the processes include EL-Nino and LA-Nina, IOD etc.
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Precipitation anomalies
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It shows that warmer March has led to below-normal precipitation over Eurasia.
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The reduced snowfall over the Eurasian landmass has historically tended to favour a stronger monsoon.
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As it happens, 2023 is expected to be an El Niño year, and El Niños tend to produce weaker monsoons. So this summer’s El Niño effect could be blunted by the lower snow cover over Eurasia.