Today's Headlines - 25 July 2023
Marine heat waves gripped world’s oceans
GS Paper - 1 (Geography)
Sweltering temperatures have induced extreme heat warnings, wildfires and poor air quality in different regions. But it isn’t just on the land that the mercury has soared – the average daily global sea surface temperature is off the charts too. Ocean temperatures have remained at record-high levels, giving rise to marine heat waves (MHWs) around the globe.
What are marine heat waves?
A marine heat wave is an extreme weather event. It occurs when the surface temperature of a particular region of the sea rises to 3 or 4 degree Celsius above the average temperature for at least five days.
MHWs can last for weeks, months or even years, according to the US government’s agency National Oceanic and Atmospheric Administration (NOAA).
At present, MHWs have gripped the north-east Pacific, the southern hemisphere in the southern Indian Ocean and the Pacific, the north-east Atlantic, tropical North Atlantic, and the Mediterranean, according to a recent forecast of the non-profit science organisation Mercator Ocean International.
MHWs can have debilitating effects on both marine ecosystems and humans. They may cause the deaths of several marine species, alter their migration patterns, lead to coral bleaching and even impact weather patterns.
MHWs can make storms stronger and severely affect coastal communities. What’s more, these disastrous consequences are set to become even worse as the world continues to get warmer, making MHWs more intense and longer.
What is the impact of marine heat waves on ocean life?
Although an increase of 3 or 4 degrees Celsius in average temperatures may not be much for humans, it can be catastrophic for marine life.
For instance, MHWs along the Western Australian coast during the summer of 2010 and 2011 caused some “devastating” fish kills — the sudden and unexpected death of many fish or other aquatic animals over a short period and mainly within a particular area — as per a 2013 study in the Journal of Marine Systems.
A different study revealed that the same MHWs destroyed kelp forests and fundamentally altered the ecosystem of the coast. Kleps usually grow in cooler waters, providing habitat and food for many marine animals.
Another example is when high ocean temperatures in the tropical Atlantic and Caribbean in 2005 led to a massive coral bleaching event.
Higher ocean temperatures, which are associated with MHWs, can make storms like hurricanes and tropical cyclones stronger.
#upsc #news #todayheadline #marine #worldoceans #temperatures #wildfires #MHWs #global #celsius #NOAA #ecosystems #humans #coastal #tropical #atlantic #caribbean #cyclones #debilitating #mediterranean #humans #devastating
Marine heat waves gripped world’s oceans
GS Paper - 1 (Geography)
Sweltering temperatures have induced extreme heat warnings, wildfires and poor air quality in different regions. But it isn’t just on the land that the mercury has soared – the average daily global sea surface temperature is off the charts too. Ocean temperatures have remained at record-high levels, giving rise to marine heat waves (MHWs) around the globe.
What are marine heat waves?
A marine heat wave is an extreme weather event. It occurs when the surface temperature of a particular region of the sea rises to 3 or 4 degree Celsius above the average temperature for at least five days.
MHWs can last for weeks, months or even years, according to the US government’s agency National Oceanic and Atmospheric Administration (NOAA).
At present, MHWs have gripped the north-east Pacific, the southern hemisphere in the southern Indian Ocean and the Pacific, the north-east Atlantic, tropical North Atlantic, and the Mediterranean, according to a recent forecast of the non-profit science organisation Mercator Ocean International.
MHWs can have debilitating effects on both marine ecosystems and humans. They may cause the deaths of several marine species, alter their migration patterns, lead to coral bleaching and even impact weather patterns.
MHWs can make storms stronger and severely affect coastal communities. What’s more, these disastrous consequences are set to become even worse as the world continues to get warmer, making MHWs more intense and longer.
What is the impact of marine heat waves on ocean life?
Although an increase of 3 or 4 degrees Celsius in average temperatures may not be much for humans, it can be catastrophic for marine life.
For instance, MHWs along the Western Australian coast during the summer of 2010 and 2011 caused some “devastating” fish kills — the sudden and unexpected death of many fish or other aquatic animals over a short period and mainly within a particular area — as per a 2013 study in the Journal of Marine Systems.
A different study revealed that the same MHWs destroyed kelp forests and fundamentally altered the ecosystem of the coast. Kleps usually grow in cooler waters, providing habitat and food for many marine animals.
Another example is when high ocean temperatures in the tropical Atlantic and Caribbean in 2005 led to a massive coral bleaching event.
Higher ocean temperatures, which are associated with MHWs, can make storms like hurricanes and tropical cyclones stronger.
#upsc #news #todayheadline #marine #worldoceans #temperatures #wildfires #MHWs #global #celsius #NOAA #ecosystems #humans #coastal #tropical #atlantic #caribbean #cyclones #debilitating #mediterranean #humans #devastating
Today's Headlines - 01 August 2023
Key takeaways of WMO report
GS Paper - 3 (Environment)
According to a new report, released by the World Meteorological Organization (WMO), Asia is the world’s most disaster-prone region and it experienced 81 weather, climate and water-related disasters in 2022. These events directly affected more than 50 million people with about 5,000 getting killed and economic damage worth $ 36 billion, the report added. Although, in 2021, the continent had been affected by around 100 natural disasters, the extent of these hazards was more prominent in 2022 — the number of people and facilities affected, and economic damage has increased.
What are the key takeaways from the report?
According to the report, while the mean temperature over Asia in 2022 was about 0.72 degree Celsius above the 1991–2020 average, it was about 1.68 degree Celsius above the 1961–1990 average.
This rise in temperatures has had some severe fallouts, including an uptick in the occurrence of extreme weather events.
For instance, droughts ravaged numerous parts of Asia in 2022. China particularly suffered the most as last year, the Yangtze River Basin, located in the country’s southwest, experienced the worst drought in the last six decades.
This not only affected crops and vegetation, as well as the drinking water supply but also caused an economic loss of about $ 7.6 billion.
Many other regions were hit by severe floods and extreme monsoon rainfalls. Pakistan is the most notable example – it received 60 percent of normal total monsoon rainfall within just three weeks of the start of the 2022 monsoon season, and the heavy rains resulted in urban and flash floods, landslides, and glacial lake outburst floods across the country.
More than 33 million people were affected, over 1,730 people died and almost eight million people were displaced, according to the report.
Apart from natural disasters, climate change has exacerbated glaciers melting in Asia due to high temperatures and dry conditions.
Four glaciers in the High Mountain Asia region, centred on the Tibetan Plateau, have recorded significant mass losses, with an accelerating trend since the mid-1990s.
At the same time, these four glaciers show an overall weaker cumulative mass loss than the average for the global reference glaciers during the period 1980–2022.
Even thesea surface temperatures in Asia are getting warmer than ever before. The report pointed out that in the north-western Arabian Sea, the Philippine Sea and the seas east of Japan, the warming rates have exceeded 0.5 degree Celsius per decade since the 1980s. It is about three times faster than the global average surface ocean warming rate.
India in report
In India, heavy rainfalls “lasting from May to September triggered multiple landslides and river overflows and floods, resulting in casualties and damage”.
In total, this flooding resulted in over 2,000 deaths and affected 1.3 million people — the disaster event caused the highest number of casualties of any disaster event in 2022 in India.
The report also said economic loss due to disasters relating to floods exceeded the average for the 2002–2021 period. Pakistan incurred a loss of over $ 15 billion, followed by China, over $ 5 billion, and India, over $ 4.2 billion.
Another extreme weather event that became a mainstay in Asia last year was heat waves.
The report noted that India and Pakistan experienced “abnormally warm conditions” in the pre-monsoon season (March–May), the report mentioned. China, Hong Kong and Japan also saw the mercury rising to record high levels in 2022.
#upsc #news #headline #WMO #report #enviroment #world #meteorological #organization #disasters #economic #temperature #asia #china #yangtze #river #basin #country #rainfalls #monsoon #pakistan #tibetan #plateau #mountain #celsius #arabian #sea #philippine #japan #glaciers
Key takeaways of WMO report
GS Paper - 3 (Environment)
According to a new report, released by the World Meteorological Organization (WMO), Asia is the world’s most disaster-prone region and it experienced 81 weather, climate and water-related disasters in 2022. These events directly affected more than 50 million people with about 5,000 getting killed and economic damage worth $ 36 billion, the report added. Although, in 2021, the continent had been affected by around 100 natural disasters, the extent of these hazards was more prominent in 2022 — the number of people and facilities affected, and economic damage has increased.
What are the key takeaways from the report?
According to the report, while the mean temperature over Asia in 2022 was about 0.72 degree Celsius above the 1991–2020 average, it was about 1.68 degree Celsius above the 1961–1990 average.
This rise in temperatures has had some severe fallouts, including an uptick in the occurrence of extreme weather events.
For instance, droughts ravaged numerous parts of Asia in 2022. China particularly suffered the most as last year, the Yangtze River Basin, located in the country’s southwest, experienced the worst drought in the last six decades.
This not only affected crops and vegetation, as well as the drinking water supply but also caused an economic loss of about $ 7.6 billion.
Many other regions were hit by severe floods and extreme monsoon rainfalls. Pakistan is the most notable example – it received 60 percent of normal total monsoon rainfall within just three weeks of the start of the 2022 monsoon season, and the heavy rains resulted in urban and flash floods, landslides, and glacial lake outburst floods across the country.
More than 33 million people were affected, over 1,730 people died and almost eight million people were displaced, according to the report.
Apart from natural disasters, climate change has exacerbated glaciers melting in Asia due to high temperatures and dry conditions.
Four glaciers in the High Mountain Asia region, centred on the Tibetan Plateau, have recorded significant mass losses, with an accelerating trend since the mid-1990s.
At the same time, these four glaciers show an overall weaker cumulative mass loss than the average for the global reference glaciers during the period 1980–2022.
Even thesea surface temperatures in Asia are getting warmer than ever before. The report pointed out that in the north-western Arabian Sea, the Philippine Sea and the seas east of Japan, the warming rates have exceeded 0.5 degree Celsius per decade since the 1980s. It is about three times faster than the global average surface ocean warming rate.
India in report
In India, heavy rainfalls “lasting from May to September triggered multiple landslides and river overflows and floods, resulting in casualties and damage”.
In total, this flooding resulted in over 2,000 deaths and affected 1.3 million people — the disaster event caused the highest number of casualties of any disaster event in 2022 in India.
The report also said economic loss due to disasters relating to floods exceeded the average for the 2002–2021 period. Pakistan incurred a loss of over $ 15 billion, followed by China, over $ 5 billion, and India, over $ 4.2 billion.
Another extreme weather event that became a mainstay in Asia last year was heat waves.
The report noted that India and Pakistan experienced “abnormally warm conditions” in the pre-monsoon season (March–May), the report mentioned. China, Hong Kong and Japan also saw the mercury rising to record high levels in 2022.
#upsc #news #headline #WMO #report #enviroment #world #meteorological #organization #disasters #economic #temperature #asia #china #yangtze #river #basin #country #rainfalls #monsoon #pakistan #tibetan #plateau #mountain #celsius #arabian #sea #philippine #japan #glaciers