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Planet at risk of heading towards ''Hothouse Earth'' state
by Stockholm Resilence Centre, agencies
An international team of scientists has published a study in Proceedings of the National Academy of Sciences (PNAS) showing that even if the carbon emission reductions called for in the Paris Agreement are met, there is a risk of Earth entering what the scientists call “Hothouse Earth” conditions.
A “Hothouse Earth” climate will in the long term stabilize at a global average of 4-5°C higher than pre-industrial temperatures with sea level 10-60 m higher than today, the paper says. At that point much of the earth would be uninhabitable.
"The impacts of a hothouse earth pathway on human societies would likely be massive, sometimes abrupt, and undoubtedly disruptive," the study said.
The authors conclude it is now urgent to greatly accelerate the transition towards an emission-free world economy.
"Human emissions of greenhouse gas are not the sole determinant of temperature on Earth. Our study suggests that human-induced global warming of 2°C may trigger other Earth system processes, often called “feedbacks”, that can drive further warming - even if we stop emitting greenhouse gases," says lead author Will Steffen from the Australian National University and Stockholm Resilience Centre.
"Avoiding this scenario requires a redirection of human actions from exploitation to stewardship of the Earth system.”
Currently, global average temperatures are just over 1°C above pre-industrial and rising at 0.17°C per decade.
The authors of the study consider ten natural feedback processes, some of which are “tipping elements” that lead to abrupt change if a critical threshold is crossed. These feedbacks could turn from being a “friend” that stores carbon to a “foe” that emits it uncontrollably in a warmer world.
These feedbacks are: permafrost thaw, loss of methane hydrates from the ocean floor, weakening land and ocean carbon sinks, increasing bacterial respiration in the oceans, Amazon rainforest dieback, boreal forest dieback, reduction of northern hemisphere snow cover, loss of Arctic summer sea ice, and reduction of Antarctic sea ice and polar ice sheets.
"These tipping elements can potentially act like a row of dominoes. Once one is pushed over, it pushes Earth towards another. It may be very difficult or impossible to stop the whole row of dominoes from tumbling over. Places on Earth will become uninhabitable if “Hothouse Earth” becomes the reality," warns co-author Johan Rockström, former executive director of the Stockholm Resilience Centre and incoming co-director of the Potsdam Institute for Climate Impact Research.
Hans Joachim Schellnhuber, Director of the Potsdam Institute for Climate Impact Research, says, "We show how industrial-age greenhouse gas emissions force our climate, and ultimately the Earth system, out of balance. In particular, we address tipping elements in the planetary machinery that might, once a certain stress level has been passed, one by one change fundamentally, rapidly, and perhaps irreversibly. This cascade of events may tip the entire Earth system into a new mode of operation.”
“What we do not know yet is whether the climate system can be safely ''parked'' near 2°C above preindustrial levels, as the Paris Agreement envisages. Or if it will, once pushed so far, slip down the slope towards a hothouse planet. Research must assess this risk as soon as possible."
Cutting greenhouse gases alone is not enough
Maximizing the chances of avoiding a “Hothouse Earth” requires not only reduction of carbon dioxide and other greenhouse gas emissions but also enhancement and/or creation of new biological carbon stores, for example, through improved forest, agricultural and soil management; biodiversity conservation; and technologies that remove carbon dioxide from the atmosphere and store it underground, the paper says.
Critically, the study emphasizes that these measures must be underpinned by fundamental societal changes that are required to maintain a “Stabilized Earth” where temperatures are ~2°C warmer that the pre-industrial.
"Climate and other global changes show us that we humans are impacting the Earth system at the global level. This means that we as a global community can also manage our relationship with the system to influence future planetary conditions. This study identifies some of the levers that can be used to do so," said co-author, Katherine Richardson from the University of Copenhagen.
Professor Steffen said countries needed to work together to "greatly accelerate the transition towards an emission-free world economy".
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The Increasing Influence of Global Warming
by Office for Disaster Risk Reduction, WMO, agencies
UN urges greater focus on fire risk following Greek wildfire tragedy
The UN Secretary-General’s Special Representative for Disaster Risk Reduction, Mami Mizutori, has expressed her condolences to Greece for the tragic loss of life in this week’s fires.
Ms. Mizutori said: “This is a truly heartbreaking tragedy and I offer my sincere condolences to the Greek government and people at this difficult time.”
She said: “There is no doubt that fire risk is increasing around the globe driven by higher temperatures, prolonged periods of drought and expansion of housing in the wildland-urban interface.
“We owe it to those who have lost their lives in Greece and elsewhere to step up efforts on wildfire suppression and prevention. Investing in disaster response and preparedness are vital to this effort considering that global losses from wildfires reached record levels last year and few parts of the world are spared from this risk as climate change multiplies the threat.”
Ms. Mizutori urged that fire hazard be given due consideration in establishing national and local strategies for disaster risk reduction which are now being developed to meet the 2020 deadline of the global plan for reducing disaster losses, the Sendai Framework for Disaster Risk Reduction 2015-2030.
In recent years the extent of burnt areas in regions such as the western United States, south-east Australia and Europe has increased dramatically. So far this year, Sweden and California have also experienced major wildfires and 2017 saw a high number of deadly fires in Europe, including in Portugal, Spain and Italy. http://bit.ly/2Ov3M2T
Drought and heat exacerbate wildfires. (WMO)
The unusually hot and dry summer in parts of the northern hemisphere has turned fields and forests into fuel for fires which are raging from the Arctic to the Mediterranean and West Coast of North America. These wildfires have caused dozens of fatalities and are devastating large regions, with far-reaching impacts for the environment, ecosystems, human health and the climate.
The wildfires are notable because they are happening in some places such as Scandinavia which are not accustomed to them. Advances in satellite technology has made it possible to monitor wildfire activity better than in the past.
In addition to the direct threat from burning, wildfires also release pollutants detrimental for human health and ecosystems. Close to the fires, smoke is a health risk because it contains a mixture of hazardous gases and small particles that can irritate the eyes and respiratory system. The effects of smoke exposure and inhalation range from eye and respiratory tract irritation to more serious disorders, including reduced lung function, bronchitis, exacerbated asthma and premature death. Exposure to particulate matter is the main public health threat from short-term exposure to wildfire smoke, according to the World Health Organization. Vegetation fires release large amounts of particulate matter and toxic gases including carbon monoxide, nitrogen oxides, and non-methane organic compounds into the atmosphere.
The northern part of the world is warming faster than the planet as a whole. That heat is drying out forests and making them more susceptible to burn. A recent study found Earth’s boreal forests are now burning at a rate unseen in at least 10,000 years.
The Intergovernmental Panel on Climate Change, in its Fifth Assessment Report, said that the frequency and extent of wildfires in southern Europe increased significantly after the 1970s as a result of fuel accumulation, climate change and extreme weather events.
* Press Conference on Climate change by the Secretary-General of the World Meteorological Organization, Professor Petteri Taalas: http://bit.ly/2QpQcic
July 28, 2018
Summer Heat Waves, by Bob Berwyn, InsideClimate News
Earth''s global warming fever spiked to deadly new highs across the Northern Hemisphere this summer, and we''re feeling the results - extreme heat is now blamed for hundreds of deaths, droughts threaten food supplies, wildfires have raced through neighborhoods in the western United States, Greece and as far north as the Arctic Circle.
At sea, record and near-record warm oceans have sent soggy masses of air surging landward, fueling extreme rainfall and flooding in Japan and the eastern U.S. In Europe, the Baltic Sea is so warm that potentially toxic blue-green algae is spreading across its surface.
There shouldn''t be any doubt that some of the deadliest of this summer''s disasters—including flooding in Japan and wildfires in Greece—are fueled by weather extremes linked to global warming, said Corinne Le Quéré, director of the Tyndall Centre for Climate Change Research at the University of East Anglia.
"We know very well that global warming is making heat waves longer, hotter and more frequent," she said.
"The evidence from having extreme events around the world is really compelling. It''s very indicative that the global warming background is causing or at least contributing to these events," she said.
The challenges created by global warming are becoming evident even in basic infrastructure, much of which was built on the assumption of a cooler climate. In these latest heat waves, railroad tracks have bent in the rising temperatures, airport runways have cracked, and power plants from France to Finland have had to power down because their cooling sources became too warm.
"We''re seeing that many things are not built to withstand the heat levels we are seeing now," Le Quéré said.
Penn State climate scientist Michael Mann said this summer''s extreme weather fits into a pattern he identified with other researchers in a study published last year. The jet stream''s north-south meanders have been unusually stationary, leading to persistent heat waves and droughts in some areas and days of rain and flooding in others, he said. "Our work last year shows that this sort of pattern ... has become more common because of human-caused climate change, and in particular, amplified Arctic warming."
Deadly Heat Waves from Canada to Japan
There are many ways to define a heat wave, but the conditions in many areas of the planet this summer have been universally recognized as severe, said Boram Lee, a senior research scientist with the World Meteorological Organization.
"From around end of June, many countries in Europe, Asia and North America have issued severe warnings," she said. The UK, U.S., Japan and Korea all had long-lasting warnings, and Japan declared the recent heat wave a natural disaster, she added.
In Europe, scientists on Friday released a real-time attribution study of the heat wave that has baked parts of northern Europe since June. They found that global warming caused by greenhouse gas pollution made the ongoing heat wave five times more likely in Denmark, and twice as likely in Ireland.
"Near the Arctic, it''s absolutely exceptional and unprecedented. This is a warning," said French heat wave expert Robert Vautard, who worked on the study for World Weather Attribution. The group previously determined that global warming made last summer''s "Lucifer" heat wave in southern Europe 10 times more likely.
"In many places, people are preparing for the past or present climate. But this summer is the future," he said.
The geographic scope and persistence of the European heat wave stands out. An area stretching from the British Isles to Eastern Europe and north to the Arctic is bright red on European heat wave and drought maps, covering an area about as big as Texas and California combined.
Crop damage is being reported in parts Norway through Sweden, Denmark and the Baltics. Depending on conditions during the next month, more widespread crop failures could raise global food prices.
In mid-July, temperatures reached all-time record highs above the Arctic Circle, around 90 degrees Fahrenheit, and hovered in the 80s for weeks at a time. In the Norwegian glacier area that Lars Holger Pilø studies, the average temperature has been 9 degrees Fahrenheit above average for the past 30 days.
"I have been working here since 2006, and we have snow records going back 60 years, and there''s nothing like what we''re seeing right now," said Pilø, part of team of ice archaeologists who are measuring the snow and ice loss and recovering historic artifacts like arrowheads and skis that were buried for millennia.
"I''m watching with a mixture of excitement and dread. I try not to think too much about it and stick to what we do, which is rescuing the artifacts coming out of the warming. I call it dark archaeology," he said. "I look at the ice and I think, dead man walking."
Norwegian Meteorological Institute climate scientist Ketil Isaksen said the extreme situation in Scandinavia fits with the pattern of global warming.
"There are so many extremes now from all over the world. We''re seeing a very common pattern. For me this is a strong climate signal. Ice that''s several thousand years old, melting in the matter of just a few weeks," he said.
Isaksen is finalizing some studies that find heat is penetrating between 30 and 50 meters deep into the ground through cracks in the rocky mountains around Norway''s fjords. Instead of just a thin skin of permafrost melting, those mountains could fall apart in large chunks when autumn rains start, threatening coastal communities with tsunamis.
"Now we have a new extreme this summer. This will probably affect slope stability, and we can expect mass movement events like debris flows and landslides in late summer," he said.
He said the studies help define new geologic hazard areas with knowledge that some of the melted mountains will see wholesale slope failure when strong rains hit. Based on the information, emergency managers are developing new early warning systems.
The Increasing Influence of Global Warming
About the same time the Norwegian researchers were uncovering ancient tools in the Arctic tundra this summer, heat records were being set in many other parts of the world.
Temperatures in Algeria reached 124 degrees Fahrenheit, setting a record for the African continent. A few weeks earlier, a city in Oman is believed to have broken a global record when it went more than 24 hours with temperatures never falling below 108 degrees. Japan set a national record of 106 amid a heat wave that has been blamed for more than 80 deaths.
Regional western heat events are becoming so pronounced that some climate scientists see the current extremes in the U.S. as a climate inflection point, where the global warming signal stands out above the natural background of climate variability.
In mid-July, a week of temperatures in the high 80s and up to 96 degrees Fahrenheit in normally cool Quebec killed more than 50 people, and while that heat wave was waning, another was building in Asia, where the Japan Meteorological Agency said that 200 of its 927 stations topped the 35 degree Celsius (95 degrees Fahrenheit) on July 15. Since then, at least 80 people have died and thousands have gone to hospitals with heat-related ailments.
"There are irrefutable scientific evidences that climate change alters both the intensity and frequency of such extreme phenomena as heat waves, and ongoing efforts are dedicated to understand how big the impact of man-made climate change is," said the WMO''s Boram Lee.
Across social media, climate scientists are responding with a collective "we warned about this," posting links to 10 years worth of studies that have consistently been projecting increases in deadly heat waves. If anything, the warnings may have been understated.
"The rise in heat waves is stronger than many climate models project," said World Weather Attribution''s Geert Jan van Oldenborgh, who measured a record high temperature outside his office in the Netherlands on July 26, then tweeted that global warming is making the heat there 20 times more likely than in 1900.
Wildfires Out of Control
Hot and dry weather also makes forests more flammable. In Greece, after a month of record and near-record heat, flames ran wild through the community of Mati on July 23, killing at least 80 people. On July 26, a blaze in Northern California jumped the Sacramento River and spawned fire tornadoes, forcing the evacuation of parts of Redding, a city of 92,000. And in Germany, residents of southern Berlin awoke Friday to the sight of smoke on the horizon, an event that will also become more common in that part of the world.
Although climate scientists are reluctant to link any one particular fire to climate change, there is plenty of scientific evidence showing how heat-trapping greenhouse gases contribute to increased fire danger.
"Weather is a product of the climate system. We are drastically altering that system, and all the weather we observe now is the product of that human-altered climate system. One result is an increase in the frequency, size and severity of large fire events," University of California, Merced researcher Leroy Westerling wrote.
University of Arizona climate researcher and geographer Kevin Anchukaitis publicized several wildfire studies from the last 10 years that all show how and why global warming is making fires bigger, more destructive and longer-lasting. "Is climate change the only factor influencing wildland fire? No, of course not—but climate change is influencing area burned and fuel aridity," he wrote.
Tyndall Centre Director Le Quéré said she faulted some media for failing to connect global warming to the current global heat wave. "This signal is very clear," she said, adding that some of the early stories about the deadly fire in Greece almost seemed to downplay a link to climate change.
On Friday, the WMO released a new statement highlighting the links between global warming and wildfires and reminding readers that "heat is drying out forests and making them more susceptible to burn."
Extreme Rainfall and Flooding
There is also still reluctance to link individual extreme flood events with global warming, despite plenty of scientific evidence that today''s global atmosphere—1 degree Celsius warmer than 100 years ago—holds much more moisture that can be delivered by regional storm systems.
Those warnings were not enough to help the more than 200 people who died in Japan in late June amid a series of record-setting torrential rain storms. Regional weather patterns certainly played a role, but ocean currents and an atmosphere juiced up by global warming likely boosted moisture for the storm.
Two years ago, Alfred Wegener Institute climate researcher Hu Yang showed how climate change is strengthening ocean currents that carry moisture from the ocean toward Japan. The research showed the currents have been getting stronger and warmer in tandem with rising atmospheric CO2 levels. Eventually, that heat is released to the atmosphere during storms, as wind or rain or both.
Yang said his continuing research is finding similar evidence that a powerful current near Japan may be "a super hotspot under global warming." As the current strengthens, it will release its energy as water vapor, fuel for storms that can cause extra heavy rains in Japan and other parts of Asia, he said.
In the U.S., June flooding in the Midwest fits a detected pattern of increasing extreme rainfalls in that region. And in late July, 10 million people in the East, from Pennsylvania to North Carolina, were under various types of flood warnings with soggy air sloshing from the Gulf of Mexico and the Caribbean over the overheated Northeastern Atlantic toward the coast.
In some cases, the scientific warnings about global warming impacts have resonated. At least parts of Europe are better prepared for heat waves now than they were in 2003, when extreme heat killed up to 70,000 people, said Le Quéré.
More cities know what they need to do to protect vulnerable people in an extreme event, she said, but they lack the money to do things like building more cooling shelters, or cooling core urban areas with green spaces and ponds.
"Maybe this is an opportunity, in a grim way, to prepare for events that will be longer and hotter," she said. "It''s not just a case of holding our breath for three weeks and saying ''it''s soon winter.'' It''s a time to push and protect vulnerable people and infrastructure."
To prepare for the new normal, people must act in the next five to 10 years, said environmental scientist Cara Augustenborg, chairperson of Friends of the Earth Europe.
"We have to consider how every new infrastructure, agricultural or development project from now on will be impacted by climate change. We need to look at planned retreat from coastlines and developing further inland, building infrastructure that is more resilient to the effects of climate change such as sea level rise and temperature extremes.
"We''ve had several years now where airport runways have melted on extremely hot days," she continued. "That''s something we need to factor in to future construction as it''s a problem that won''t go away."
Society also needs to think about food security, she said. "That''s what I really lose sleep over," she said. "Our available arable land is declining now as our global population is booming. It doesn''t take much in the way of extreme weather to have a major impact on food supplies."
* New research reveals regions of world will suffer heatwaves beyond the limit of human survival if climate change continues unchecked.
New scientific research shows that humid heatwaves that kill even healthy people within hours will strike repeatedly towards the end of the century thanks to climate change, unless there are heavy cuts in carbon emissions.
“Northern China home to 400 million people is going to be one of the hottest spots for deadly heatwaves in the future,” said Prof Elfatih Eltahir, at the Massachusetts Institute of Technology, US, who led the new study. The projections for China’s northern plain are particularly worrying because many of the region’s 400 million people are farmers and have little alternative to working outside.
“China is currently the largest contributor to the emissions of greenhouse gases, with potentially serious implications to its own population,” he said. “Continuation of current global emissions may limit the habitability of the most populous region of the most populous country on Earth.”
The new analysis assesses the impact of climate change on the deadly combination of heat and humidity, which is measured as the “wet bulb” temperature (WBT). Once the WBT reaches 35C, the air is so hot and humid that the human body cannot cool itself by sweating and even fit people sitting in the shade die within six hours.
A WBT above 31C is classed by the US National Weather Service as “extreme danger”, with its warning stating: “If you don’t take precautions immediately, you may become seriously ill or even die.”
The research, published in the journal Nature Communications, found fatal WBTs of 35C would strike the north China plain repeatedly between 2070 and 2100, unless carbon emissions are cut. Shanghai, for example, would exceed the fatal threshold about five times and the “extreme danger” WBTs would occur hundreds of times. Even if significant carbon cuts are made, the “extreme danger” WBT would be exceeded many times.
Previous research by Eltahir and colleagues showed that the Gulf in the Middle East, will also suffer heatwaves beyond the limit of human survival if climate change is unchecked, particularly Abu Dhabi, Dubai, Doha and coastal cities in Iran. The fatal 35C WBT was almost reached in Bandar Mahshahr in Iran in July 2015, where 46C heat combined with 50% humidity.
The scientists also analysed south Asia in 2017 and found it too is at risk of killer 35C WBT heatwaves in places. Even outside the extreme hotspots, three-quarters of the 1.7bn population – particularly those farming in the Ganges and Indus valleys – would be exposed to “extreme danger” levels of humid heat towards the end of the century.
Heatwaves & Health. (The Lancet)
22,000 people, half of them elderly, were reportedly taken to hospital with symptoms of heat stroke during the past month''s heatwave in Japan, where record temperatures exceeded 41°C. Exceptionally high and persistent July temperatures also baked north America and Europe, and set the stage for catastrophic forest fires not only in Greece, but also above the Arctic circle in Alaska and Lapland. Climate change makes heatwaves more frequent and severe. Yet, unlike other natural disasters—with which, based on impact, they should be rightly grouped—heatwaves do not elicit an immediate cross-sectoral response to protect life. Given the prospect of 7000 heat-related deaths per year in the UK by 2050, that lackadaisical approach must change. The world is facing a true planetary health emergency.
Killer heatwaves are a relatively recent and poorly understood threat. There is no universal definition of a heatwave. Meteorologists tend to refer to an increase of 5°C above the average maximum temperature from 1961–90 that lasts for 5 days or longer. Heatwaves disrupt economies, agriculture, transport, and utilities. They exacerbate existing problems like drought and present profound risks to health. Densely-constructed urban centres present special risks from concentrated heat that dissipates slowly: the heat island effect. 20 thousand deaths were attributed to the prolonged European heatwave of 2003. In the UK that year, deaths increased by a third among residents in London, people older than 75 years, and those in care homes.
Heatwaves increase deaths from cardiovascular and respiratory conditions. People at the extremes of age are most susceptible to heat, but so are those who are poor or socially isolated. Poverty hinders adaptation in many ways. Inferior housing can overheat at lower temperatures, while the cost of water or electricity creates a barrier to bathing or mechanical cooling. In Paris, France, 90% of people who died during the 2003 heatwave lived alone.
Populations around the world are at risk from heatwaves, even in countries like India that are accustomed to high temperatures. In Karachi, Pakistan, 65,000 people were taken to hospital with heat-related symptoms in 2015. Developing countries are particularly susceptible, as adaptation to climate change is costly and outdoor manual labour is more common. Additionally, lower resource countries might have shortages of electricity during heatwaves that disadvantage those who are unable to afford alternative sources of power.
Providing health care in heatwaves presents challenges. Acute demand soars, doubling requests for consultations and increasing in-patient admissions. Moreover, many hospitals are poorly designed to cope with heat, built instead with insulation to retain warmth and prone to high internal heat gains from patients, staff, and equipment. The blasé call for wider use of air-conditioning ignores the fact that most energy is derived from fossil fuels. Therefore, electricity for air-conditioning contributes to the pollution that drives climate change, while also producing waste heat that adds to urban heat islands. More sophisticated responses that incorporate heat resilience into design are required.
To summarise the challenges presented by hotter summers in the future and to direct the government''s response, the UK House of Commons Environmental Audit Committee released a report Heatwaves: adapting to climate change on July 26. The report catalogues poorly judged decisions by the UK government that have increased vulnerability to heatwaves. For example, stopping climate adaptation funds in 2015, relaxing targets for water conservation despite projected decreases in future supply, encroaching on green spaces in urban areas, exempting England from sustainable urban drainage systems that are required elsewhere in the UK, and inadequate communication of climate risks. There is much to be rectified, starting with regulations about heatwaves for new buildings. At present, one in five homes in the UK overheats to more than 26°C. To construct schools, hospitals, or factories today that are not resilient to climate change represents a poor investment and condemns generations of users to misery.
The House of Commons report provides facts from which adaptation to climate change can be planned, beginning with clear communication and public education about risks. The report concludes that the Department of Health and Social Care should provide leadership within the government. This is an important opportunity to place health at the centre of decision-making about climate change, to recognise that threats to health, like heatwaves, are shared internationally, to build more resilient communities, and, most importantly, to limit further emissions of greenhouse gases. http://bit.ly/2AJ4kze
* In the UK, the Environmental Audit Committee reports that heat-related deaths are set to treble by 2050. Mary Creagh MP, Chair of the Environmental Audit Committee:
“Heatwave warnings are welcomed as barbecue alerts, but they threaten health, wellbeing and productivity. The Met Office has projected that UK summer temperatures could regularly reach 38.5°C by the 2040s. The Government must stop playing pass the parcel with local councils and the National Health Service and develop a strategy to protect our ageing population from this increasing risk.. Heatwaves cause premature deaths from cardiac, kidney and respiratory disease. There will be at least an extra 7,000 heat-related deaths every year in the UK by 2050 if the Government does not take action.. The Government needs to do more to warn the public of the health risks of heatwaves'': http://bit.ly/2uSVFF2
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