Tag Archives: heat wave

“Record-shattering” heatwaves will be much more likely in the future

Today’s fast pace of global warming virtually guarantees more extreme temperature records around the world, according to a new study. Much of the US, Europe, and Asia will experience more deadly heatwaves in the coming decades, just like the one recently experienced in the Pacific Northwest, with shattered temperature records. In other words, we’re just getting started with the heatwaves.

NASA computer model image of temperature departures from average on June 27 during the Pacific Northwest heat wave. Image credit: NASA Earth Observatory.

Heatwaves are not only a nuisance but can also be very dangerous, leading to illness and even death, especially among the most vulnerable (like older adults and the very young). Because of climate change, they are occurring more frequently, are getting more intense, and are lasting longer than they did in the past. 

“The main message is that we need to prepare for more record heat events in the coming decades that shatter previous record temperatures by large margins,” Erich Fischer, lead author, told Axios. “Because we are in a period of very rapid warming, we need to prepare for more heat events that shatter previous records by large margins.”

The researchers argued that climate change is still not much appreciated as a driver of extreme heat, despite the growing pace of emissions guaranteeing more extreme temperature records in the coming decades. Global average temperatures have already grown 1ºC compared to pre-industrial times, a trend set to continue in the future decades. However, this doesn’t mean that the entire globe will uniformly be hotter by one degree — the shifts are irregular and often more extreme in some parts of the world.

Heating up

Fisher and a team at ETH Zurich used computer models and records of past weather events to examine how the chances for record heat waves have been shifting and will continue to change as global warming continues. They focused on the occurrence of week-long heatwaves, such as the one that happened in the Pacific Northwest. 

Under a high-emissions scenario, heatwaves that break previous records by roughly 5ºC would become two to seven times more likely in the next three decades and three to 21 times more likely from 2051 to 2080, according to the study’s findings. Such extreme heatwaves would be impossible without global warming, the researchers said.

“This study underscores something that has been apparent in the record weather extremes we’ve seen this summer: dangerous climate change is here, and it’s now simply a matter of how dangerous we are willing to let it get,” climate expert Michael Mann from Pennsylvania State University, not part of the new research, told The Guardian. 

In a recent study, Mann and a global team of researchers concluded that the occurrence of a heatwave with maximum daily temperatures as observed in some areas of the US and Canada was “virtually impossible” without climate change. The temperatures were so extreme that they lie far outside the range of historically observed temperatures. 

Our best chance of limiting the effects of climate change is by reducing our greenhouse gas emissions. While we’re making some progress on this front, it’s far too underwhelming to avoid problems like this. Keeping the planet within 2ºC of warming will require a quick decarbonization of our economy and a transition to renewable energy.

The study was published in the journal Nature. 

Death Valley breaks all-time world heat record — again

For the second year in a row, Death Valley, California, reached the highest daily average temperature ever observed on Earth (reliably). According to the US National Weather Service, temperatures reached a 130 degrees Fahrenheit (54.4ºC) last Friday, edging the previous record of 129.9 degrees Fahrenheit set on August 16, 2020. 

Image credit: Flickr / Roadsidepictures

Climate heating

The blistering temperatures occurred amid a heatwave in the West region of the United States, where the areas between southern Nevada, Central Valley in California, and interior Oregon were especially affected. Intensified by climate change, the heatwave is also fueling fast-moving wildfires. A total of 59 large blazes are currently burning across a dozen states.

The new record was registered at the Stovepipe Wells weather station in the northern part of Death Valley National Park. This is separate from the frequently referenced temperature measurements at Death Valley’s Furnace Creek, located further southeast. The record will now have to be reviewed by the World Meteorological Organization (WMO).

Still, the measurements at Stovepipe Wells are probably legitimate as they were produced from the U.S. Climate Reference Network, the gold standard for weather observation. The network relies on high-quality instruments that monitor weather is stable, undisturbed locations, according to the National Oceanic Atmospheric Administration.

The record was set after three days of extreme temperatures in Death Valley, which began with the 130-degree high at Furnace Creek on Friday. If confirmed, it would mark the planet’s highest temperature since at least 1931. Only two other measurements have been higher: a 134-degree reading from Furnace Creek in 1913 and a 131-degree reading from Tunisia in 1931, neither of which are as reliable as this measurement. 

The legitimacy of these measurements is questioned by climatologists such as Christopher Burt, an expert on weather extremes. Burt wrote that the 1913 reading isn’t possible from a meteorological perspective, while the 1931 reading has “credibility issues.” This means the readings at Furnace Creek from 2020 and 2021 could be the highest pair of reliably measured temperatures observed on Earth.

Reliable measurements

Still, there are other factors to contemplate that could affect the recent record at Furnace Creek . William Reid, a climatologist expert on Death Valley meteorology, said that an increase in vegetation and structures built in the vicinity of the Furnace Creek site in recent decades has allowed the station to record hotter temperatures.

“An increase in vegetation and some man-made structures not too far south of the station have resulted in poorer ventilation through the station area. Since the station is above a bare and sandy surface, hot air along the ground during afternoon sunshine is less effectively mixed away from the instrumentation. The result is higher temperature readings during the afternoon comparably,” Reid wrote

Whether the record is officially confirmed or not, it’s clear that heatwaves are getting worse – and climate change has a lot to do with it. They are occurring more frequently, are more intense, and are lasting longer than they did in the past. Global temperatures have already increased by 1ºC compared to pre-industrial times, and show little sign of slowing down. We’re now entering into a period of climate heating and we can expect plenty more records to come in future years.

This is the third heatwave in just three weeks in the West, following the Pacific Northwest event at the end of June and the blast in the Southwest in the middle of the month. A panel of scientists recently agreed that the current heatwave would have been “virtually impossible” without climate change. Even in today’s warming world, the heat was a once-in-a-millennium event.

Last month was hottest June on record in North America

North America is suffering from killer heat. June was the hottest month on record, and the record-breaking heat spread to multiple regions of the United States and Canada, where all-time record daily temperature was broken for a whopping three days in a row.

Image credit: Flickr / Joe Chung

North America was 1.2 degrees Celsius (34.2 degrees Fahrenheit) above the 1991-2020 average in June, according to the Copernicus Climate Change Service (C3S) — and it showed. It was also the second warmest June on record for Europe Copernicus, the EU’s Earth observation program, produces its data for world temperatures from computer-generated analyses, using billions of measurements from satellites, aircraft, and weather stations.

“These heatwaves are not happening in a vacuum. They are happening in a global climate environment that is warming and which makes them more likely to occur,” C3S climate scientist Julien Nicolas told AFP. “They are just the latest examples of a trend that’s projected to continue into the future and is tied to the warming of our climate.”

A series of unusually hot days are usually referred to as an extreme heat event or a heatwave. They are more than uncomfortable and can lead to illness and death, especially among older adults and the very young. Because of climate change, they are occurring more frequently, are more intense, and are lasting longer than they did in the past. In Oregon alone, heatwaves killed 107 people, and the number is unfortunately expected to rise in the following weeks — many found alone without air conditioning or a fan. In Washington state, 57 deaths were reported, 13 of which were in Seattle. In British Columbia, 486 sudden deaths occurred during the heat, triple the usual number. To make matters even worse, temperatures are rising year after year.

“Every decade the world has increased the rate of greenhouse gas emissions and that has increased the rate of warming. So, of course, heat records are being broken more frequently,” Friederike Otto of the Environmental Change Institute at Oxford University told the BBC. “People rarely drop dead on the street, but die quietly in their poorly insulated and un-air-conditioned homes.”

Whopping heat

The heatwave stretching from the US state of Oregon to Canada’s Arctic territories was blamed on high-pressure ridge trapping warm air in the region. Temperatures in cities of Portland, Oregon, and Seattle, Washington reached levels not seen since record-keeping began in 1940, according to the National Weather Service. 

On Monday, Portland had 46ºC (115 Fahrenheit), and Seattle 42ºC (108 Fahrenheit), while Vancouver on the Pacific coast registered 30ºC (86 Fahrenheit). Nordic countries were also affected. Kevo, in Lapland, the northernmost region of Finland, recorded 33.6ºC (92.5 Fahrenheit), the hottest day since 1914, said the local STT news agency

Michael Reeder, a professor of meteorology at Australia’s Monash University, told the BBC the events on the European and North American continents were linked. A tropical low in the western Pacific, near Japan, had disturbed the atmosphere, creating ripples around the hemisphere. “It’s like plucking a guitar string. The disturbance propagated along the jet stream,” Reeder said.

Canada issued alerts for British Columbia, Alberta, and parts of Saskatchewan, Manitoba, Yukon, and the Northwest Territories. The US National Weather Service issued a similar warning, asking people to “stay in air-conditioned buildings, avoid strenuous outdoor activities, drink plenty of water, and check on family members.”

Schools and Covid-19 vaccination centers closed in the Vancouver area due to the heatwave. Officials set up temporary water fountains and misting stations on street corners and stores ran out of portable air conditioners and fans. Cities in Canada and the US opened emergency cooling centers and outreach workers handed out water.

“We are in the midst of the hottest week British Columbians have ever experienced, and there are consequences to that, disastrous consequences for families and for communities,” British Columbia Premier John Horgan told a news conference. “How we get through this extraordinary time is by hanging together,” he said.

The 2015 Paris Agreement on climate change calls countries to limit the increase in global temperatures at “well below” two degrees Celsius, and 1.5 degrees Celsius if possible. Human activity has driven global temperatures up about 1 degree Celsius so far – which could potentially reach 3 degrees Celsius by the end of the century. At this rate, staying within the climate objective seems increasingly unlikely.

Heatwave sets temperature records across Europe

A heatwave has sent temperatures soaring across western Europe over the weekend, with records broken in the UK, Spain, and Italy. Relief is soon to arrive but weather agencies are warning over more and longer heatwaves, a direct consequence of a warmer world.

The Fountain of the Naiads in Rome. Credit Flickr David McKelvey (CC BY-NC-ND 2.0)

Cities across Western Europe saw high temperatures anywhere from 10 to 15ºC (50 to 59 Fahrenheit) degrees above normal. The phenomenon was linked to areas of high pressure in northern Africa and led to tourists and locals swarming to the beaches across Europe, making it difficult to maintain physical distancing.

The temperature in San Sebastian on northern Spain reached 42ºC (107 Fahrenheit), which was the hottest weather there since records began in 1955. Meanwhile, the city of Palma on the island of Mallorca saw a record temperature of 40.6ºC (105 Fahrenheit).

The Spanish weather agency, Aemet, said tropical nights, when temperatures don’t fall below 20ºC (68 degrees Fahrenheit), were frequent in many parts of Spain in July and that the annual number of days in heatwave conditions doubled since the 1980s, which is linked to climate change.

Up north, United Kingdom residents also experienced record temperatures, with the national weather agency reporting a reading of 37.8ºC (100 Fahrenheit) at Heathrow Airport near London on Friday. This made it the hottest day of the year so far and the third-hottest on record.

People packed beaches around the British coast, not always obeying the social distancing norms. The city of Brighton on England’s south coast asked visitors to say away, concerned over the number of people in the city.

“Large numbers make it impossible to maintain physical distancing,” the city council said.

In Italy, more than a dozen cities were put on alert as temperatures peaked around 40ºC (104 Fahrenheit) on Friday and Saturday. In Rome, tourists and residents try to escape from the extreme heat by cooling down in public fountains and staying in the shade. The heat made it more difficult to wear face masks to prevent the spread of coronavirus, people said.

“Your breath gets very warm — your glasses, there are lots of problems,” Ana Gonzalez, a tourist in Rome, told Reuters. “But you put it all aside when you think that it’s protection and there’s no choice about wearing it.”

There’s no single accepted definition of a heatwave across the globe due to variations in climate conditions in different world regions. Nevertheless, they are usually defined by an unseasonably hot period, usually 5ºC or more above the average daily maximum, that lasts at least three days.

Heatwaves usually happen in Europe when high atmospheric pressure draws up hot air from northern Africa, Portugal, and Spain, rising temperatures and increasing humidity. They are not uncommon, but they are being amplified by a rise in global temperatures and are likely to become more frequent.

Australia’s heatwave breaks all-time temperature record for the second day straight

Australia is going through one of its most severe heat events so far, feeding the bushfire season. The country has already broken records for peak temperatures and this could be just the start, as weather forecast estimates the heatwave to continue.

Credit Wikipedia Commons

The nationally averaged maximum temperature on December 18 was 107.4 degrees Fahrenheit (41.9 Celsius), according to the Australian Bureau of Meteorology. This broke the previous record of 105.6 degrees (40.9 Celsius) which was set just the day before.

Before the current heat event, the hottest temperature the country had seen was on January 7, 2013, with 104.5 degrees (40.3 Celsius). Now a combination of drought, fires and two-record hottest days has created a problematic scenario.

The forecast anticipates “catastrophic” fire conditions, the most severe category, in South Australia, as the rising temperatures are combined with a wind shift that complicates firefighting actions. The possibility of a new national record to be broken again is also on the table.

Usually, temperature records in Australia were broken just by fractions of a degree. This made this week’s records quote unusually. At the same time, having consecutive records broken in the same week is also rare. All this has been possible due to the severe and longer-lasting heatwave.

The heat started over the weekend in Western Australia. Now it has already reached southeastern areas of the country. These areas have also been affected by some of the massive bushfires that had been happening in the country since the beginning of the spring.

Two volunteer firefighters died while trying to stop the expansion of the Green Wattle Creek fire in southwestern Sidney, as the vehicle rolled over. Emergency warnings have already been issued for the Gospers Mountain Fire, which has been called a mega-fire because of its size.

Several businesses and government areas have even stopped working outside due to concerns over smoke pollution. Workers mainly stay indoors to avoid smoke. Sports fields, municipal pools, and daycare centers in Sidney were shut down. Smoke from a bush fire can worsen asthma and other respiratory conditions.

While the country experiences this crisis, Prime Minister Scott Morrison decided to take a one-week family vacation to an undisclosed destination – a move questioned by environmental activists and opposition leaders. There was a climate protest outside Morrison’s residence, which the police broke down.

The environment is the second most important issue for Australians, right behind the economy, according to a survey done by the Scanlon Foundation in July and August before the heatwave started.

The temperature has increased in Australia one degree Celsius since 1910, with most of the warming concentrated since 1950. There has been an increase in the frequency of extreme heat events and the severity of drought conditions. Of the 10 warmest years on record in the country, nine have happened since 2005.

Cool roofs could help to deal with heatwaves in California

As global heating continues to take its toll, one of its more direct consequences has been the longer and more intense heatwaves across the globe and its health consequences. Looking for palliatives, researchers have highlighted the potential of so-called cool roofs in California — one of the areas that’s more vulnerable to urban heatwaves.

Credit: Flickr

The study, carried out by researchers at the Department of Energy’s Lawrence Berkeley National Laboratory, showed that if every building in California sported “cool” roofs by 2050, these roofs would help contribute to protecting people from the consequences of heatwaves.

A cool roof is a roof designed to reflect more sunlight and thus, absorb less heat than a standard roof. They can be made of highly reflective tiles or shingles or be coated in a highly reflective type of paint. Nearly any type of building can benefit from a cool roof, the EPA says.

Researchers estimate heatwaves are likely to become two to 10 times more frequent across the state by mid-century — but if cool roofs were adopted throughout California’s most populous areas by 2050, they would bring heatwave exposures by 35 million, compared to an estimated 80 million cases in 2050 with no increase in cool roofs.

“Urban spaces are a small fraction of the globe, but they are where most people live,” said Pouya Vahmani, a postdoctoral research fellow in Berkeley Lab’s Climate and Ecosystem Sciences Division and lead author of the study. “If we’re able to cool those areas even a little bit, it can have a huge impact on health and roll back significant impacts of climate change.”

The study wanted to predict heat wave occurrences across California’s 29 major urban counties between now and 2050. They used regional climate conditions between 2001 and 2015 as a starting point to simulate mid-century climate under two global warming scenarios.

They combined the climate conditions with high-resolution satellite images, which allowed them to incorporate urban features like buildings, which absorb and release heat. Then, the researchers used county-level population estimates for 2050 to assess population exposure to future heat waves.

“We wanted to gain a better picture of future climate change risks for California’s urban environments and adaptation options,” said Andrew Jones, a scientist in Berkeley Lab’s Climate and Ecosystem Sciences Division and co-author of the study. “Making such refined and realistic predictions can help urban planners and citizens prepare for heat events in an increasingly warming future.”

The study found that heatwaves with air temperatures exceeding 35 degrees Celsius (95 degrees Fahrenheit) and lasting at least three consecutive days become two to 10 times more frequent under future global warming scenarios. With the added burden of urban centers getting more populous, the researchers expect that by 2050 there will be 80 million heatwave exposure cases in California each year, compared to an average of 37 million cases annually under current climate conditions.

Following this finding, the study looked at the effectiveness of cool roofs in mitigating heatwave impacts. They repeated the same high-resolution regional climate simulations, only this time replacing all existing building roofs with cool roofs.

They found that if every building in California sported cool roofs by 2050, it could bring down the annual number of heatwave exposures in California to 45 million, from 80 million. This mitigation potential surprised even the research team, which wasn’t expecting such strong results.

Nevertheless, the 100% conversion to cool roofs by 2050 will be very challenging. While cities like Los Angeles mandate cool roofs for new constructions, retrofitting existing buildings will also be expensive.

At the same time, the positive effect of cool roofs will be limited to reducing day time temperatures when the roofs reflect sunlight. At night, when roads and packed buildings slowly release heat, these roofs aren’t capable of directly providing cooling benefits.

Extreme heat to become the new normal in the US

If there’s one clear sign of climate change, it’s extreme heat. And people all across the US know it as they have been facing it this summer with long heat waves. According to new research, this will likely be the new normal across the country.

A weather forecast in the US shows days with extreme heat. Credit: Flickr


Climate change will probably make extreme heat conditions and their health risks much more frequent in almost every part of the US, according to research published in the journal Environmental Research Communications.

“Our analysis shows a hotter future that’s hard to imagine today,” study co-author Kristina Dahl, a climate scientist at the Union of Concerned Scientists, said in a statement. “Nearly everywhere, people will experience more days of dangerous heat in the next few decades.”

By 2050, hundreds of US cities could see around 30 days each year with heat index temperatures above 100 degrees Fahrenheit (37.7 Celsius) if nothing is done to rein in global warming. The heat index is what the temperature feels like to the human body when relative humidity is combined with the air temperature — so it’s a measure of how temperature actually feels.

This is the first study to take the heat index — instead of just temperature — into account when determining the impacts of global warming. The number of days per year when the heat index exceeds 100 degrees will more than double nationally, according to the study.

“We have little to no experience with ‘off-the-charts’ heat in the U.S.,” said Erika Spanger-Siegfried, lead climate analyst at the Union of Concerned Scientists and report co-author. “These conditions occur at or above a heat index of 127 degrees. Exposure to conditions in that range makes it difficult for human bodies to cool themselves.”

The research suggests that there will be few areas of the country able to avoid these extreme heat events, except for some high-altitude mountainous regions. Currently, the only place that experiences these “off-the-charts” days is the Sonoran Desert on the border of southern California and Arizona.

The National Weather Service of the US typically issues a “heat advisory” when a maximum heat index is expected to hit at least 100°F for two or more days, and an “excessive heat warning” when it will hit at least 105°F for two or more days. These heat levels can lead to health risks such as dehydration and heatstroke.

The expected increase in heatwaves will require additional efforts to help people cope, especially those who aren’t used to it, the study concluded. This should be in line with a further reduction in global greenhouse emissions, now considered not sufficient to meet the 2ºC global warming limit established by the Paris Agreement.


In the last 50 years, droughts and heat waves destroyed 1/10 of crops

Agriculture is a very risky line of work. It’s almost inevitable that once in a while extreme weather will take a huge toll on the crop yields. This is common knowledge, but the quantitative impact of droughts and heat waves has only recently been investigated in great detail. A paper published in Nature by researchers at University of British Columbia found droughts cut a country’s total crop yield by 10 percent, and heat waves by 9 percent. Floods and cold spells oddly did not affect crop production in a significant way. These effects vary from country to country and another surprising finding is that crops in developed countries suffer up to twice as many losses than those in developing countries.


Image: Pixabay

Navin Ramankutty, a geographer from the University of British Columbia and colleagues looked at 2,800 extreme weather events collected by the Emergency Events Database (EM-DAT) and the impact these had on 16 different cereals, including oats, barley, rye and maize, grown in 177 countries.

Due to droughts and heat waves, some three billion tons of these crops were lost from 1964 to 2007.

“We don’t think about it much, but rice, wheat and maize alone provide more than 50 percent of global calories,” Dr. Ramankutty told the NY Times. “When these grain baskets are hit, it results in food price shocks, which leads to increasing hunger.”

This is a double problem. For one, we lose 10% of crop yields, but the carbon emissions that were expelled in the process stay in the atmosphere, heat the planet and drive more freak weather.

Droughts caused the most damage in North America, Europe and the Australasia where they destroyed 20% of cereal production. In Asia and Africa these figures were much lower standing at 12% and 9%, respectively. That’s because, the authors argue, in developed countries farmers grow their crops more uniformly. This makes them more vulnerable to droughts than more diversified patches, as seen in Africa for instance.

The analysis suggests that droughts are causing more damage than ever, and become worse in time. Droughts in 1985 caused losses of about 14% while earlier ones only destroyed 7% of the production. Climate projections suggest that droughts and heat waves will become more frequent and severe.

The authors conclude that over the last five decades, droughts and heat waves have dramatically damaged national agricultural production all over the world. They highlight, however, that while damage to cereal production is significant, this effect is short term and output generally rebounds following a disaster.

Australia’s 2013 Heat Waves linked to Man-made Climate Change, 5 Studies Conclude

Australia went through two almost unbearable consecutive summers. Of course, Australia is a naturally hot country, but the temperatures were extremely high even for them. Record temperatures were recorded and heat waves swept throughout the entire country. Now, five separate studies published today conclude that the blazing summers can be blamed on man-made climate change.

Sizzling Hot


The January 2014 southeastern Australia heat wave was a significant heat wave event which affected most of southeastern Australia from 13 to 18 January 2014. In 2013 the situation was even worse, as most of the country had temperatures of over 42 degrees Celsius (107 Fahrenheit). This spike in heat waves comes in the context of record breaking high temperatures across Australia over the past five years which have spurred heated discussions regarding man-made climate change. Are we to blame for the heat waves in Australia?

No less than five separate papers, all part of a grander report concluded that the answer is ‘yes’. Explaining Extreme Events of 2013 From a Climate Perspective, published in the Bulletin of the American Meteorological Society (BAMS) features a total of 22 separate studies focusing on 16 different extreme weather events that occurred last year. However, aside for the Australian heat waves, researchers couldn’t find a connection between man-made climate change and extreme weather events. This doesn’t necessarily mean that the connection doesn’t exist – the matter is so complex that a direct link is often times extremely hard to find. However, for the particular cases in Australia, the link is clear.

“When we look at the heat across the whole of Australia and the whole 12 months of 2013, we can say that this was virtually impossible without climate change,” said David Karoly, a climate scientist at the University of Melbourne who led some of the research.

The study relied on computer models to show how the climate would have been in the absence of human emissions. This type of research is widely known to be imperfect, and sometimes yields conflicting results – but in this case, scientists were surprised to observe the unanimity of the results. Basically, no matter how you parametrize the model, the result is the same: without human emissions, there would have been now heat waves. Results convinced even skeptics:

“The evidence in those papers is very strong,” said Martin P. Hoerling, an American scientist with the National Oceanic and Atmospheric Administration who has often been skeptical of claimed links between weather events and global warming.

Heat Waves often cause wildfires, which greatly affect the population and wildlife. Image via NBC.

Two traps

Climate scientists have often argued that even if extreme weather events weren’t directly caused by climate change, their effects are likely accentuated by it. Again, this issue is hard to demonstrate, and it’s rare that climate models reach a consensus. For example, in the same report, the California drought was also analyzed. The models agreed that man-made climate change wasn’t the cause of it, but they disagreed on whether or not it was accentuated by global warming. Some results indicated ‘yes’, some indicated a ‘no’.

There are two traps which we must avoid here – first of all, we shouldn’t point the finger at climate change for every freak weather event. Extreme weather has happened before and it will happen in the future. Humans might be responsible for some events, but even without us, there would still be freak weather. The other trap is even more dangerous. It implies not doing anything, simply because there is no certainty. Let’s sum up what we know: climate change is happening; it’s real, and we’re causing it. There is a scientific consensus on the issue, there’s little discussion there. Whether or not extreme weather is associated with it, that’s a different story. As dire as it sounds, there are far worse implications than that.