2010 Northern Hemisphere summer

The 2010 Northern Hemisphere summer heat waves included severe heat waves that impacted most of the United States, Kazakhstan, Mongolia, China, Hong Kong, North Africa and the European continent as a whole, along with parts of Canada, Russia, Indochina, South Korea and Japan during May, June, July, and August 2010. The first phase of the global heatwaves was caused by a moderate El Niño event, which lasted from June 2009 to May 2010. The first phase lasted only from April 2010 to June 2010, and caused only moderate above average temperatures in the areas affected. But it also set new record high temperatures for most of the area affected, in the Northern Hemisphere. The second phase (the main, and most devastating phase) was caused by a very strong La Niña event, which lasted from June 2010 to June 2011. According to meteorologists, the 2010–11 La Niña event was one of the strongest La Niña events ever observed. That same La Niña event also had devastating effects in the Eastern states of Australia. The second phase lasted from June 2010 to October 2010, caused severe heat waves, and multiple record-breaking temperatures. The heatwaves began in April 2010, when strong anticyclones began to develop, over most of the affected regions, in the Northern Hemisphere. The heatwaves ended in October 2010, when the powerful anticyclones over most of the affected areas dissipated.

The heat wave during the summer of 2010 was at its worst in June, over the Eastern United States, Middle East, Eastern Europe and European Russia, and over Northeastern China and southeastern Russia. June 2010 marked the fourth consecutive warmest month on record globally, at 0.66 °C (1.22 °F) above average, while the period April–June was the warmest ever recorded for land areas in the Northern Hemisphere, at 1.25 °C (2.25 °F) above average. The previous record for the global average temperature in June was set in 2005 at 0.66 °C (1.19 °F), and the previous warm record for April–June over Northern Hemisphere land areas was 1.16 °C (2.09 °F), set in 2007. The strongest of the anticyclones, the one situated over Siberia, registered a maximum high pressure of 1040 millibars. The weather caused forest fires in China, where three in a team of 300 died fighting a fire that broke out in the Binchuan County of Dali, as Yunnan suffered the worst drought in 60 years by February 17. A major drought was reported across the Sahel as early as January. In August, a section of the Petermann Glacier tongue connecting northern Greenland, the Nares Strait and the Arctic Ocean broke off, the biggest ice shelf in the Arctic to detach in 48 years. By the time the heatwaves had ended in late October 2010, about $500 billion (2011 USD) of damage was done, in the Northern Hemisphere alone.

More than 55,000 people died during the heat wave in Russia. The World Meteorological Organization stated that the heat waves, droughts and flooding events fit with predictions based on global warming for the 21st century, include those based on the Intergovernmental Panel on Climate Change's 2007 4th Assessment Report. Some climatologists argue that these weather events would not have happened if the atmospheric carbon dioxide was at pre-industrial levels.

Events

Europe

Europe in general

A heat wave hit Eastern Europe as exceptionally strong jet stream winds blew in from the Sahara across the Balkans and into both Poland and Ukraine on June 10. The Polish Institute of Meteorology and Water Management (IMGW) warned of temperatures in Poland exceeding for the next 5 days, followed by heavy winds, rain storms, thunderstorms and possible flooding especially in the north-west of the country and neighbouring parts of Germany.

The period between June 13 and 19 saw a low pressure zone move south eastwards taking a shallow pool of cooler air south eastwards across from the North Atlantic into Ireland and most of the United Kingdom.

As the floods eased in Central Europe and the Balkans, apart from those in Romania, temperatures began to climb across Western Europe, including Frankfurt am Main in Germany and the United Kingdom on June 30.

On July 2, Brussels saw its hottest day since 1976 and France, Germany and the Spanish resort Benidorm experienced record temperatures. Several heavy thunderstorms hit the Low Swiss Alps, accompanied by heavy sleet in some places.

On July 3, a heat wave hit parts of Ryazan Oblast, Krasnodar Krai, and the cities of Copenhagen, Bucharest and Budapest, killing a Romanian man with heat stroke. Heavy thunderstorms hit the High Swiss Alps, accompanied by heavy snow in some places.

On July 6, 3 low pressure areas moved towards and settled near the Black Sea after a week a high pressure in the region's jet stream far northward in its trek through Europe. The National Oceanic and Atmospheric Administration's GFS numerical model predicted the same weather for the following week.

A meteorological synoptic pressure corridor ran from Germany and Poland east and northeast to western and north western Russia causing temperatures that were 4 °C, 8 °C and in one case 10 °C above the seasonal norm. Cities from Berlin and Warsaw to Kyiv, Minsk, Moscow and St. Petersburg may well reach the 33 °C to 35 °C range.

Berlin and Warsaw recorded temperatures of 33 °C, while highs of nearly 34 °C in Moscow broke records. Earlier in June, temperatures in Minsk hit 30 °C, while temperatures as high as 34 °C were observed in Kyiv.

By July 8, a major heat wave hit most of Europe, European Russia and North America.

Both the French and Belgian authorities were on alert to respond to possible incidences of heat-related illnesses following the death of a Frenchman in the north of the country due to heat exhaustion. Brussels saw its next hottest day since 1976, while Portugal and Germany experienced record high temperatures.

Austria's Central Institute for Meteorology and Geodynamics (ZAMG) issued public safety warnings on the 8th as it predicted temperatures as high as by the weekend. The centre expected similar conditions continuing into the beginning of next week, where it would end in a heavy Alpine downpour.

The Swiss Meteorological Office reported that a record 34.8C was set in Basel and warned of both forest fires in the persistently drought-hit southern canton of Valais. The Swiss Health Office offered the public safety advice. The ozone level rose badly and was more than twice the permitted level at 257 microgrammes per cubic metre in Lugano on Friday, and things were in a generally bad condition across the Swiss Alps as a whole. Extreme heat and ozone levels were also harming tourists at the Gotthard Road Tunnel on the 8th and 9th.

The Swiss Ornithological Institute, based in Sempach, said young swifts were stifling to death and others were jumping out before they could fly properly, as temperatures reached in their under the roof nests. Most of them lived at the institute care home.

A heavy rainy thunderstorm hit Zürich on the 10th and the Swiss-French border. They also threatened to close the Avoriaz stage of the Tour de France cycle race.

The UK declared a heat wave, set at Met Office Level 2/4, for the period 9–16 July 2010 for South East England and East Anglia. This was after temperatures reached in London and night-time temperatures leveled around .

The UK recorded its highest temperature of the year, , in Gravesend, Kent, as the British Health Protection Agency gave out health advice and claimed there had been "several hundred" more deaths than normal over the previous two weeks and some appeared to be linked to the heat on the 11th.

July 11 and 12 saw heatstroke make several people ill throughout the Iberian Peninsula, European Russia, Belarus, eastern Poland and Ukraine.

The heat wave that left Morocco for the Iberian Peninsula on the 11th was attributed to the regional hot air currents that departed from the Sahara in Northern Africa at about 1000 meters (1 km) in altitude, which facilitated a movement in the hot air towards the Balkans and Ukraine via the Straits of Gibraltar, Spain and Italy.

On July 11, temperatures skyrocketed in Vienna, Berlin, Munich, Amsterdam, Madrid, Lisbon, Zurich and Bucharest. More heavy thunderstorms hit the High Swiss Alps, accompanied by heavy snow in some places.

Forty passengers were hospitalised with dehydration in Germany when 3 ICE trains' air conditioning system broke down in temperatures approaching 40 °C on the 11th. One thousand luckier passengers switched trains. Deutsche Bahn apologized for its ICE trains breaking down.

Hartmut Buyken, chairman of passenger association Pro Bahn, told radio station hr-INFO that the trains were ruined by cost-cutting measures, and weren't selling as well in international markets as the French TGV trains.

On the 12th, Portugal, Spain, Germany, Great Britain, Belgium, France, and the Czech Republic all suffered the hottest temperatures of the year, and the heat wave was most likely to continue over the weekend, according to German meteorologists.

Most of Germany, including Berlin, recorded temperatures of in some places. On the popular North Sea island of Helgoland, the temperature was only 20.5 degrees. In Berlin, the highest temperature was recorded at as 3 more non-air conditioned local passengers trains had to be evacuated due to overheating of the interior passenger compartments, leading to passengers getting heat stroke, Deutsche Welle reported. Hans-Dieter Muehlenberg, chief of a local rescue squad in Berlin told the German news agency DAPD he had found the temperature in a local train had reached and that nine people had to be hospitalized for dehydration. Later on, official reports from the rescue squad denied that 9 people reported dead had died and that the air conditioning systems fail to cool the trains in temperatures over . Deutsche Bahn paid 500 Euros for the heat victims without a doctors note. …