Published 18:59 IST, February 20th 2021
What is happening in Texas? Will India face such drastic changes in climatic conditions?
While conditions overwhelmed Texas, the US National Weather Service explained that the boiling state is suddenly freezing over because of an “Arctic outbreak".
Texas is known for its sprawling deserts and excruciating heatwaves, however, right now, the US state is blanketed in a thick layer of ice. Power outages, caused by a combination of high demand, power plants crippled by the weather, and a grid that is cut off from the rest of the country, have left millions of people shivering in the dark. The state is seeing some of its coldest temperatures in more than 30 years, with some areas even breaking records that are more than a century old. The US President Joe Biden has already declared a state of emergency as for the first time, winter-storm warnings are in place in all 254 counties.
‘Sudden Stratospheric Warming’ explained
While conditions overwhelmed Texas, the US National Weather Service (NWS) explained that the boiling state is suddenly freezing over because of an “Arctic outbreak” that originated just about the US-Canada border, bringing a winter snowstorm as well as plummeting temperatures. The meteorologists explained that the extreme pattern was initiated by a large and recognizable phenomenon called ‘Sudden Stratospheric Warming’, or SSW. Texans’ current chill was caused by rapid heating in the stratosphere, the second-lowest section of the atmosphere, 8-50km above the Arctic.
SSW’s are a natural occurrence that happens every couple of winters and portends extreme weather in the weeks following them. This happens because when the Arctic warms rapidly it disrupts a spinning mass of cold air - the polar vortex - a semi-permanent weather system that is present each winter. The meteorologists explained that normally jet streams wind around the vortex and acts like a lasso of sorts, keeping the cold air trapped inside. However, when it gets warm in the Arctic, the jet stream weakens and elongates, allowing the cold air to plunge south.
This enables a broad mountain of warm air to form over the Arctic. The warm air then acts as an atmospheric block, redirecting the jet stream and bitterly cold air southward. It is worth noting that cold air outbreaks such as these are normally kept in the Arctic by a series of low-pressure systems, however, this one moved through Canada and spilled into the US last week.
As a result, hundreds of daily record lows were set within the past week, focused on the south-central Plains States. According to CBS News, dozens of all-time records were also set as the unprecedented cold gripped cities and towns unaccustomed to and unprepared for the bitter blast. Temperatures in the city of Dallas for example will reach a high of -10C next week when it should be more like 15C at this time of the year. Currently, the temperature in Dallas is already colder than in Anchorage, Alaska.
Extreme weather across the globe
The Associated Press reported that the meteorologists call this year’s SSW event one of the “biggest, nastiest, and longest-lasting ones” they’ve seen. Further, the experts noted that the event could be considered “not one, but three polar vortex disruptions”. As per reports, the rare cold snap has even reached northern Mexico.
The recent extreme weather was also not limited to the US as to when the jet stream is extreme in one region, it is often extreme all across the globe. In Saudi Arabia, snow-covered camels made for a rare sight. Snow also fell in Jerusalem, parts of Jordan and Syria, and Spain, while at the same time record heat was also impacting other parts of the Middle East like Iraq. Further, experts have warned that there could be widespread impacts on weather across vast swaths of North America and Eurasia.
Climate change in India
Meanwhile, it is worth mentioning that India is among the top ten most affected countries in the Global Climate Risk Index 2021 published by the Bonn-based environmental think tank Germanwatch. Another study also found that monsoon rainfall over the course of the century will get even more severe for southern India because of global heating. The researchers have said that a narrow band of tropical heavy rainfall, is moving steadily north. The researchers looked at 27 different climate models to conclude that by the end of the century, the intertropical convergence zone (ITCZ) will migrate towards eastern Africa and the Indian Ocean, even as the atmosphere in Earth’s northern hemisphere heats up.
This will have a varied impact, including “future increases of drought stress in south-eastern Africa and Madagascar, intensifying flooding in southern India and greater drought stress in Central America—large hydrological hotspots of global change that will have considerable impacts on food security and biodiversity”. The report further states that this will result in an increase in India’s monsoon rainfall, as well as an increase in extreme rainfall events.
Updated 18:59 IST, February 20th 2021