HEAT DOMES - GEOGRAPHY
News: Heat
domes causing winter heat waves in Europe: What are heat domes and how does it
occur
What's in the news?
● As
India grapples with one of the coldest Januarys with cold waves gripping
northern states, several parts of Europe on the contrary witnessed an
unprecedented winter heat wave over the New Year’s week.
● The
change in winter waves is being called
an ‘extreme event’ by the experts as seven countries across the continent
recorded the hottest January ever, according to a report.
Key takeaways:
● The
temperatures in parts of Europe,
which usually hosts significantly cold winters, have risen by 10 to 20 degrees
Celsius above normal.
● As
per a Washington Post report, at least seven European countries recorded their
hottest January weather ever and these included Poland, Denmark, the Czech
Republic, the Netherlands, Belarus, Lithuania and Latvia.
Heat domes:
● 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.
● A
2022 study concluded that heat domes are
a phenomenon catalysed by climate change and its impacts and if not taken
seriously could become a once-in-a-decade event if global temperatures aren’t
kept under two degree Celsius above pre-industrialisation levels.
What is the relationship between heat domes and the
jet stream?
● The
heat dome’s formation is related to the behavior 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.