20/07/2020

Climate Change: Siberian Heatwave 'Clear Evidence' Of Warming

BBC - Justin Rowlatt

Wildfires were made more severe by high temperatures and strong winds. Getty Images

A record-breaking heatwave in Siberia would have been almost impossible without human-caused climate change, a study has found.

The Russian region's temperatures were more than 5C above average between January and June of this year.

Temperatures exceeded 38C in the Russian town of Verkhoyansk on 20 June, the highest temperature ever recorded north of the Arctic circle.

The Arctic is believed to be warming twice as fast as the global average.

An international team of climate scientists, led by the UK Met Office, found the record average temperatures were likely to happen less than once every 80,000 years without human-induced climate change.

That makes such an event "almost impossible" had the world not been warmed by greenhouse gas emissions, they conclude in the study.

In a news release, the scientists describe the finding as "unequivocal evidence of the impact of climate change on the planet".

It is, says Prof Peter Stott of the Met Office, the strongest result of any attribution study to date.


In the latest episode of Climate Check, Sarah Keith-Lucas look at the record temperatures in the Arctic Circle

Attribution studies attempt to work out the role that human-induced climate change plays in major weather events.

Climate scientists use computer simulations to compare the climate as it is today with the climate as it would have been without human influence to see how likely different weather events would have been.

The researchers say that the current Siberian heat "has contributed to raising the world's average temperature to the second hottest on record for the period January to May".

What happens in the Arctic doesn't stay in the Arctic

The changing Arctic climate is of huge importance here in the UK.

Four of the six main systems that determine this country's weather are driven by conditions in the Arctic, said Dr Katharine Hendry of Bristol University.

She was one of the lead authors on a paper published last month that suggested a series of extreme weather events could be linked to changes in the Arctic.

The so-called "Beast from the East", in the winter of 2018, is one.

It involved Arctic air blasting the country, driving temperatures below 0C for several days. Over half a metre of snow fell in some areas.

Arctic land surface temperature anomalies from 19 March to 20 June 2020. NASA

The storm is reckoned to have caused over £1bn of damage and claimed 10 lives.

The paper published last month also cites the storms and floods in February this year and ones back in 2015 as other possible examples of Arctic-linked changes.

"The link between the Arctic and UK weather is through the jet stream," said Prof Stott, referring to the ribbon of fast-moving air high up in the atmosphere.

The jet stream helps move weather systems around the globe.

But sometimes it creates "blocking" patterns that can cause weather systems to stall.

The unusually sunny spring experienced in the UK this year was caused by a blocking pattern that allowed high pressure systems to dominate the UK for months on end.

State of emergency

The heatwave in Siberia was caused by the same pattern but with even more dramatic results.

The extreme temperatures led to a cascade of natural and human disasters which prompted Russian President Vladimir Putin to declare a state of emergency in early June.

A vast fuel spill was caused by the collapse of a reservoir containing 20,000 tonnes of diesel near the Russian city of Norilsk in late May.


The BBC's Steve Rosenberg travels to the forest to see how Russians tackled 2019's wildfires

Arctic wildfires are estimated to have led to the release of 56 megatonnes of CO2 in June.

At the same time, there has been widespread melting of the permafrost and reports of unusually large swarms of Siberian silk moths that have damaged trees, making them more susceptible to fire.

Uncertain future

It is well-known that the Arctic is warming at twice the rate of the rest of the planet.

Arctic temperatures are estimated to have risen 2C since 1850 compared with 1C globally.

What impact that will have on the world's weather is less certain.

"Looking at the geological record, we don't think we've had CO2 levels as high for about five million years," said Dr Hendry. "So we really don't know what to expect into the future."

"We are," she said, "in uncharted territory".

This year's Siberian heatwaves shows just how extreme conditions can become.

What worries many scientists is that this new climate era we are entering means many places now experience weather conditions beyond anything local ecosystems - or indeed human communities - have evolved to endure.

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Climate Change: Summers Could Become 'Too Hot For Humans'

BBC - David Shukman

Some Singapore health care staff have been working in stifling heat. Image copyright Ng Teng Fong General Hospital

Millions of people around the world could be exposed to dangerous levels of heat stress - a dangerous condition which can cause organs to shut down.

Many live in developing countries, and do jobs that expose them to potentially life threatening conditions.

These include being out in the open on farms and building sites or indoors in factories and hospitals.

Global warming will increase the chances of summer conditions that may be "too hot for humans" to work in.

When we caught up with Dr Jimmy Lee, his goggles were steamed up and there was sweat trickling off his neck.

An emergency medic, he's labouring in the stifling heat of tropical Singapore to care for patients with Covid-19.

There's no air conditioning - a deliberate choice, to prevent the virus being blown around - and he notices that he and his colleagues become "more irritable, more short with each other".

And his personal protective equipment, essential for avoiding infection, makes things worse by creating a sweltering 'micro-climate' under the multiple layers of plastic.

"It really hits you when you first go in there," Dr Lee says, "and it's really uncomfortable over a whole shift of eight hours - it affects morale."

Working in PPE in a tropical climate can be extremely uncomfortable. Image copyright Ng Teng Fong General Hospital






One danger, he realises, is that overheating can slow down their ability to do something that's vital for medical staff - make quick decisions.

Another is that they may ignore the warning signs of what's called heat stress - such as faintness and nausea - and keep on working till they collapse.

What is heat stress?

It's when the body is unable to cool down properly so its core temperature keeps rising to dangerous levels and key organs can shut down.

It happens when the main technique for getting rid of excess heat - the evaporation of sweat on the skin - can't take place because the air is too humid.


Dr Angie Bone of Public Health England offers some tips and dispels some myths on staying cool

And as Dr Lee and other medics have found, the impermeable layers of personal protection equipment (PPE) - designed to keep the virus out - have the effect of preventing the sweat from evaporating.

According to Dr Rebecca Lucas, who researches physiology at the University of Birmingham, the symptoms can escalate from fainting and disorientation to cramps and failure of the guts and kidneys.

"It can become very serious as you overheat, and in all areas of the body."

How can we spot it?

A system known as the Wet Bulb Globe Temperature (WBGT) measures not only heat but also humidity and other factors to give a more realistic description of the conditions.

Back in the 1950s, the US military used it to work out guidelines for keeping soldiers safe.

When the WBGT reaches 29C, for example, the recommendation is to suspend exercise for anyone not acclimatised.

Yet that's the level Dr Lee and his colleagues are regularly experiencing at Singapore's Ng Teng Fong General Hospital.

And at the top of the scale - when the WBGT registers 32C - the US says strenuous training should stop because the risk becomes "extreme".



But levels that high have recently been recorded inside hospitals in Chennai in India by Prof Vidhya Venugopal of the Sri Ramachandra University.

She's also found workers in a salt pan enduring a WBGT that climbs during the day to 33C - at which point they have to seek shelter.

And in a steel plant, a ferocious level of 41.7C was recorded, the workers being among the most vulnerable to what she calls "the huge heat".

"If this happens day-in, day-out, people become dehydrated, there are cardiovascular issues, kidney stones, heat exhaustion," Prof Venugopal says.

What impact will climate change have?

As global temperatures rise, more intense humidity is likely as well which means more people will be exposed to more days with that hazardous combination of heat and moisture.

Prof Richard Betts of the UK Met Office has run computer models which suggest that the number of days with a WBGT above 32C are set to increase, depending on whether greenhouse gas emissions are cut.

The US military developed heat stress guidelines to keep its soldiers safe. Image copyright Getty Images

And he spells out the risks for millions of people already having to work in the challenging combination of extreme heat and high humidity.

"We humans evolved to live in a particular range of temperatures, so it's clear that if we continue to cause temperatures to rise worldwide, sooner or later the hottest parts of the world could start to see conditions that are simply too hot for us."

Another study, published earlier this year, warned that heat stress could affect as many as 1.2bn people around the world by 2100, four times more than now.

What solutions are there?

According to Dr Jimmy Lee, "it's not rocket science".

People need to drink plenty of fluid before they start work, take regular breaks and then drink again when they rest.

His hospital has started laying on "slushie" semi-frozen drinks to help the staff cool down.

But he admits that avoiding heat stress is easier said than done.

For him and his colleagues, going for rests involves the laborious process of changing out of PPE and then back into a new set of equipment.

Avoiding heat stress is easier said than done. Image copyright Getty Images



There's a practical problem as well - "some people do not want to drink so they can avoid having to go to the toilet," he says.

And there's a professional desire to keep working whatever the difficulties so as not to let colleagues and patients down at a time of crisis.

People who are highly motivated can actually be at the greatest risk of heat injury, says Dr Jason Lee, an associate professor in physiology at the National University of Singapore.

He's a leading member of a group specialising in the dangers of excessive heat, the Global Heat Health Information Network, which has drawn up guidelines to help medics cope with Covid-19.

It's spearheaded by the World Health Organization (WHO), the World Meteorological Organization (WMO) and the US weather and climate agency Noaa.






Dr Lee says that as well as measures like rest and fluids - and shade for outdoor workers - a key strategy for resisting heat stress is to be fit.

"By keeping yourself aerobically fit, you're also increasing your heat tolerance, and there are so many other benefits too."

And he sees the challenge for medics, sweating inside their PPE as they deal with Covid-19, as "almost like a full dress rehearsal" for future rises in temperature.

"This climate change will be a bigger monster and we really need a coordinated effort across nations to prepare for what is to come.

"If not," he says, "there'll be a price to be paid."

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(US) Cities Are Becoming Climate Death Traps

New Republic - 

A new era of heat waves is here. We aren’t ready.

A man cools off in the spray of a fire hydrant during a heat wave in Philadelphia. Jessica Kourkounis/Getty Images

As the coronavirus pandemic continues throughout the United States, another deadly pandemic comes out to strike in the summer: extreme heat. Year after year, more people are dying because it’s simply too hot. As of right now, both this country and others lack even an accurate way of counting those deaths—let alone a comprehensive plan to reduce them. Thanks to climate change, it’s about to get much worse.

For the past week, the American South and Southwest have been experiencing record-breaking temperatures. The National Oceanic and Atmospheric Administration has predicted above-average heat for nearly the entire U.S. this summer. Unprecedented, early-summer heat waves roasted the Middle East in May and Siberia in June, setting the latter on fire. Arizona had its earliest-ever hundred-degree heat wave in April—and another 110 degree heat wave in May. Spain endured 105 degree heat this month.

When the heat index, a “feels-like” combination of temperature and humidity, reaches 104 degrees Fahrenheit indoors or out, human body temperature risks rising above the typical roughly 99 degrees Fahrenheit. When body temperature rises above 104 degrees, the consequences can be fatal within 30 to 60 minutes.

“Heat-related deaths are notoriously difficult to track because the role of heat isn’t always obvious. One 2017 study found that extreme heat can kill people in 27 different ways,” Juanita Constible, senior advocate, climate and health at the National Resources Defense Council, told me. “If someone dies of a heart attack during a heat wave, there’s a good chance that’s how their death will be recorded by officials, even if high temperatures were the trigger.”

Many scientists argue that official heat-death counts underestimate substantially. According to the World Health Organization, 166,000 people died due to heat waves between 1998 and 2017, but the true figure may be far higher. In the U.S., the Centers for Disease Control and Prevention only count deaths where heat illness is explicitly noted, so the official CDC count of heat-triggered deaths sits at just around 600 per year. Epidemiologists estimate that the real figure may be closer to 12,000—20 times higher than the official count.

Climate change is making heat waves longer, hotter, and more deadly. Scientists estimate that 80 percent of record-breaking heat waves would not have occurred without human-caused warming due to greenhouse gas emissions. And urban areas, in particular, face special risk of heat deaths because of the heat island effect, in which dark pavement, roofs, and concrete absorb additional heat, making temperatures much hotter than the reported weather in any given city.

In the U.S., heat deaths have more than doubled in Arizona in the last 10 years. Last year, a dangerous heat wave hit while storms left residents in the D.C. and New York City metro areas without power. Power outages can be deadly in a heat wave because without air conditioning, many people can’t cool off. In two heat deaths in a 2018 Arizona heat wave, the deceased were found indoors with a broken air conditioning unit that they couldn’t afford to fix.

“Some people won’t use their air conditioning because they’re afraid of the bills,” Patricia SolĂ­s, executive director of the Knowledge Exchange for Resilience at Arizona State University, told National Geographic. “They think they’re OK without it, but that’s how people die.”

“There are huge policy gaps in the U.S. with respect to extreme heat protections,” Rachel Licker, a senior climate scientist at the Union of Concerned Scientists, told me. “We found that without real action on climate change, by midcentury more than 250 cities across the U.S. are projected to experience 30 or more days with a heat index above 100 degrees Fahrenheit. This includes many cities that historically haven’t experienced this level of extreme heat.”

Low-income communities are especially vulnerable. A 2020 study in Environmental Research Letters found that residents in low-income census tracts were less likely to use air conditioners when temperatures got hot. Heat wave exposure also disproportionately affects communities of color that have faced housing discrimination. Researchers at Portland State University and the Science Museum of Virginia found that urban neighborhoods denied municipal services during the mid-twentieth century are now the hottest areas in 94 percent of the 108 cities analyzed.

Extreme heat is a labor issue, as well. “One of the most urgent needs is an enforceable heat health standard for all workers from the [Occupational Safety and Health Administration],” said Constible. The current rule “has too much wiggle room for employers.”

 Licker pointed to the proposed Asuncion Valdivia Heat Illness and Fatality Prevention Act of 2019, which has yet to get out of the House Committee on Education and Labor, as a potential solution. The bill, sponsored by Democratic Representative Judy Chu of California, is named after Asuncion Valdivia, a California farmworker who died of a heat stroke in 2004 after picking grapes for 10 hours in 100 degree weather. The U.S. Postal Service has also received criticism for its role in workers’ heat deaths, for example in a troubling report from HuffPost this past week.

But killer heat is a worldwide phenomenon. In Europe, heat waves killed as many as 70,000 in 2003 and more than 1,500 last year. Good heat wave adaptation measures—such as handing out water at train stations, asking people to check on the elderly, and opening air-conditioned shelters for residents—likely contributed to the substantial reduction in deaths from 2003 to 2019. Accurate weather forecasting also allowed for greater preparedness. Still, just 5 percent of European households are air conditioned and scientists estimate that three degrees Celsius of warming could kill an additional 86,000 people each year in the EU.

While China and Japan are used to some sweltering-hot summers, record-breaking heat waves have nevertheless proved deadly. Consecutive heat waves in 2018 and 2019 in Japan hospitalized tens of thousands and killed hundreds. Japan doesn’t use excess mortality to calculate heat-related deaths like Europe does, which means that, as in the U.S., these numbers may be huge undercounts. In China, extreme heat combines with poor air quality to produce harmful ozone. Scientists estimate that three degrees of global warming could kill an additional 30,000 people each year in China.

Meanwhile, the impact of extreme heat on the global south remains underreported in Western media. Since developing countries tend to lack the cooling infrastructure present in North America and East Asia, regions in India, Bangladesh, and Pakistan could soon face regular summer heat waves that are impossible to survive.

A recent Tokyo Institute of Technology study shows that heat-related deaths in Jakarta are expected to increase by 15 times by 2060. And while some regions of Africa are used to heat waves as a regular occurrence, the heat island slums of large cities such as Nairobi can create fatal conditions. A 2017 John Hopkins study found that temperatures in Kibera, one of the largest “slum” settlements in Nairobi, were typically 5 to 10 degrees higher than the official weather report.

The dual threat of extreme heat and the coronavirus makes for an especially challenging summer for policymakers and city-dwellers. Many cities this year and for each additional year that the pandemic persists will have to choose between opening public cooling centers and risking transmission of Covid-19 or keeping them closed and risking preventable heat-related deaths.

And the coronavirus also complicates the labor aspect of extreme heat. The current U.S. heat standard, for example, which is only a recommendation that employers take precautions when temperatures reach a certain threshold, was created in pre-Covid times. “A heat standard is especially important this summer because of the Covid-19 pandemic,” said Constible. “The masks and other protective gear needed to slow transmission of the virus have the potential to trap heat and increase heat-health risks to some workers.”

Faced with record temperatures, many cities in the U.S. have taken aggressive adaptation measures. “Dozens of cities and some counties and states have mandatory, incentivized or city-led initiatives using features such as cool roofs, cool pavements, and trees,” Laura Brush, resilience fellow at the Center for Climate and Energy Solutions, told me. “However, funding is a significant barrier for many communities, especially during the pandemic.”

“More diverse funding sources and innovative finance mechanisms are needed to invest in resilience projects. These could include a national infrastructure bank, loan programs, and tax incentives for companies and individuals,” Brush said. Brush points to Louisville, Kentucky’s regional climate and health assessments and cool roof rebate and installation programming as one effective example of a city taking action.

The tragedy of heat-related deaths is that they are almost always preventable. Distributing free air conditioners, paying residents’ summer cooling bills, and simply encouraging people to check in on vulnerable relatives or neighbors can save lives. All of these are extremely feasible policy measures.

At the same time, nothing will slow the urban heat-death pandemic like climate mitigation and reducing greenhouse gas emissions. Limiting global temperature rise to 1.5 degrees Celsius (2.7 degrees Fahrenheit), for example, could save 2,700 lives per year in New York City alone, according to recent estimates. What’s known for sure is that ignoring either approach—the immediate or the long-term—will come with a body count.

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