What is fueling extreme heat, wildfires and flooding sweeping across the globe?

As reported by Bloomberg, while climate change remains a central factor in driving temperatures to unprecedented levels, the situation is more complex than that. The intricate interplay between the Earth and its atmosphere allows weather patterns in one area to exert influence on distant parts of the globe.

High and low-pressure zones play a significant role in establishing these connections, forging links between weather conditions in different locations. Meteorologists refer to this phenomenon as “teleconnections,” and it revolves around the movement of air within the atmosphere, Bloomberg noted.

The presence of high and low-pressure zones is responsible for bringing extreme heat to certain regions and heavy rainfall and flooding to others. Typically, these weather systems traverse across the globe. However, the current situation is different; the atmospheric carousel seems to be stuck in one position, remaining stationary for several weeks. Unfortunately, forecasts indicate that this stationary pattern is expected to persist for the foreseeable future.

“The meandering river of wind that encircles the globe and creates our weather,” noted climate scientist Jennifer Francis, adding, “Right now, it’s unusually stuck in place,” said Francis of the Woodwell Climate Research Center in Massachusetts. 

“The multiple devastating heat domes and flooding events around the Northern Hemisphere in recent weeks are indeed connected,” Francis further reported.

As the domes of high pressure remain stationary, the extreme heat has resulted in devastating consequences.

Record-breaking temperatures have been linked to a significant increase in fatalities in Mexico. In California’s Death Valley National Park, conditions were so severe that a medical helicopter was unable to reach the scene where a 71-year-old man was dying. Phoenix, the fifth-largest city in the US, experienced an unprecedented 21 days with temperatures surpassing 110F (43C). Wildfires have erupted in Greece and Switzerland, and Rome experienced all-time high temperatures, while Tokyo shattered a 150-year-old heat record.

While the high-pressure systems bring scorching heat and calamity, the low-pressure systems are causing their own havoc with heavy rainfall. In India, prolonged heat waves have given way to torrential downpours, resulting in extensive damage due to flooding. China is facing threats of floods in Beijing and Tianjin, and the US Northeast has experienced two consecutive weekends of fatal flooding.

Paul Pastelok, a senior meteorologist at AccuWeather Inc., described the pressure systems as interconnected like a chain, where everything across the globe is linked together. This interconnection creates a complex web of weather patterns and influences, leading to the diverse and extreme conditions experienced worldwide.

Bloomberg further noted that one of the clearest examples of how the teleconnections work is seen with El Niño, the phenomenon in the equatorial Pacific that can upend weather patterns the world over. As surface waters become much warmer than usual, trade winds weaken or can even reverse. These changes then ripple around the globe. The world is now under its first El Niño weather in nearly four years.

On top of all this, the ocean temperatures are also setting new highs. 

“Once you get extremely warm oceans, it is easier to maintain heat waves” as more humidity gets unleashed, said Daniel Swain, a climatologist at the University of California Los Angeles.

Scientists are investigating a hypothesis suggesting that, under specific conditions, waves in the jet streams might result in the entrapment of high and low-pressure systems, causing them to remain stationary, Bloomberg noted.

“And that would indeed be at least consistent with what we are seeing, at least times, this summer,” Swain said in a live stream presentation Wednesday. “It is still a hypothesis with a growing amount of evidence in its favour, but not an overwhelming amount — that’s my current personal assessment.” Still, he added, “it’s increasingly likely that there is” something to the theory. 

Updated: 21 Jul 2023, 08:38 AM IST

As reported by Bloomberg, while climate change remains a central factor in driving temperatures to unprecedented levels, the situation is more complex than that. The intricate interplay between the Earth and its atmosphere allows weather patterns in one area to exert influence on distant parts of the globe.

High and low-pressure zones play a significant role in establishing these connections, forging links between weather conditions in different locations. Meteorologists refer to this phenomenon as “teleconnections,” and it revolves around the movement of air within the atmosphere, Bloomberg noted.

The presence of high and low-pressure zones is responsible for bringing extreme heat to certain regions and heavy rainfall and flooding to others. Typically, these weather systems traverse across the globe. However, the current situation is different; the atmospheric carousel seems to be stuck in one position, remaining stationary for several weeks. Unfortunately, forecasts indicate that this stationary pattern is expected to persist for the foreseeable future.

“The meandering river of wind that encircles the globe and creates our weather,” noted climate scientist Jennifer Francis, adding, “Right now, it’s unusually stuck in place,” said Francis of the Woodwell Climate Research Center in Massachusetts. 

“The multiple devastating heat domes and flooding events around the Northern Hemisphere in recent weeks are indeed connected,” Francis further reported.

As the domes of high pressure remain stationary, the extreme heat has resulted in devastating consequences.

Record-breaking temperatures have been linked to a significant increase in fatalities in Mexico. In California’s Death Valley National Park, conditions were so severe that a medical helicopter was unable to reach the scene where a 71-year-old man was dying. Phoenix, the fifth-largest city in the US, experienced an unprecedented 21 days with temperatures surpassing 110F (43C). Wildfires have erupted in Greece and Switzerland, and Rome experienced all-time high temperatures, while Tokyo shattered a 150-year-old heat record.

While the high-pressure systems bring scorching heat and calamity, the low-pressure systems are causing their own havoc with heavy rainfall. In India, prolonged heat waves have given way to torrential downpours, resulting in extensive damage due to flooding. China is facing threats of floods in Beijing and Tianjin, and the US Northeast has experienced two consecutive weekends of fatal flooding.

Paul Pastelok, a senior meteorologist at AccuWeather Inc., described the pressure systems as interconnected like a chain, where everything across the globe is linked together. This interconnection creates a complex web of weather patterns and influences, leading to the diverse and extreme conditions experienced worldwide.

Bloomberg further noted that one of the clearest examples of how the teleconnections work is seen with El Niño, the phenomenon in the equatorial Pacific that can upend weather patterns the world over. As surface waters become much warmer than usual, trade winds weaken or can even reverse. These changes then ripple around the globe. The world is now under its first El Niño weather in nearly four years.

On top of all this, the ocean temperatures are also setting new highs. 

“Once you get extremely warm oceans, it is easier to maintain heat waves” as more humidity gets unleashed, said Daniel Swain, a climatologist at the University of California Los Angeles.

Scientists are investigating a hypothesis suggesting that, under specific conditions, waves in the jet streams might result in the entrapment of high and low-pressure systems, causing them to remain stationary, Bloomberg noted.

“And that would indeed be at least consistent with what we are seeing, at least times, this summer,” Swain said in a live stream presentation Wednesday. “It is still a hypothesis with a growing amount of evidence in its favour, but not an overwhelming amount — that’s my current personal assessment.” Still, he added, “it’s increasingly likely that there is” something to the theory. 

Updated: 21 Jul 2023, 08:38 AM IST