Why in News?

• Several parts of Europe is witnessing an unprecedented winter heat wave.
• Calling it an “extreme event”, experts said that temperatures increased 10 to 20 degrees Celsius above normal.
• According to a report published in the Washington Post, the continent is experiencing an extreme warm spell because of the formation of a heat dome over the region.

What’s in today’s article?

• What is a Heat Dome?
• What is the relationship between heat domes and the jet stream?
• Is Climate Change responsible for heat domes?
• News Summary

 What is a Heat Dome?

• A heat dome occurs when an area of high-pressure traps warm air over a region, just like a lid on a pot, for an extended period of time.
• The longer that air remains trapped, the more the sun works to heat the air, producing warmer conditions with every passing day.
• Heat domes generally stay for a few days but sometimes they can extend up to weeks, which might cause deadly heat waves.
• Scientists suggest that any region of high pressure, whether a heat dome or not, forces air to sink and once it reaches the ground, it gets compressed and becomes even warmer.
• Moreover, when air sinks, it gets drier and further raises the temperature of the area.

What is the relationship between heat domes and the jet stream?

• The heat dome’s formation is related to the behaviour of the jet stream — an area of fast-moving air high in the atmosphere.
• The jet stream is believed to have a wave-like pattern that keeps moving from north to south and then north again.
• When these waves get bigger and elongated, they move slowly and sometimes can become stationary.
• This is when a high-pressure system gets stuck and leads to the occurrence of a heat dome.

Is Climate Change responsible for heat domes?

• Although heat domes are likely to have always existed, researchers say that climate change may be making them more intense and longer.
• They suggest with the rising temperatures, it is expected that the jet streams will become more wavy and will have larger deviations, causing more frequent extreme heat events.

News Summary:

• On the first day of the year, seven countries in Europe recorded their warmest January.
• Temperatures were at least 10 to 20 degrees Celsius above normal from France to western Europe.
• Climatologists suggested that the temperatures surged to summer or springtime levels.
  • For example, at Korbielów, a small village in Poland, the mercury reached 19 degree Celsius – a temperature the region is more used to in May.
  • It is 18 degree Celsius above the one degree Celsius yearly average for January.