Lethal Heating: 03/18/21

18/03/2021

Climate Crisis: Recent European Droughts 'Worst In 2,000 Years'

The Guardian - Damian Carrington

Study of tree rings dating back to Roman empire concludes weather since 2014 has been extraordinary

A pharmacy sign displaying the temperature in Paris on 25 July 2019. Photograph: Bertrand Guay/AFP/Getty Images

The series of severe droughts and heatwaves in Europe since 2014 is the most extreme for more than 2,000 years, research suggests.

The study analysed tree rings dating as far back as the Roman empire to create the longest such record to date. The scientists said global heating was the most probable cause of the recent rise in extreme heat.

The heatwaves have had devastating consequences, the researchers said, causing thousands of early deaths, destroying crops and igniting forest fires. Low river levels halted some shipping traffic and affected the cooling of nuclear power stations. Climate scientists predict more extreme and more frequent heatwaves and droughts in future.

The study also found a gradual drying of the summer climate in central Europe over the last two millennia, before the recent surge. The scientists ruled out volcanic activity and solar cycles as causes of this long-term trend and think subtle changes in Earth’s orbit are the cause.

“We’re all aware of the cluster of exceptionally hot and dry summers we’ve had over the past few years,” said Prof Ulf Büntgen, of Cambridge University, who led the study. “Our results show what we have experienced is extraordinary. The series is unprecedented for the last 2,000 years.”

The available data ends in 2018, but 2019 and 2020 also had very hot European summers.

Climate change: ‘human fingerprint’ found on global extreme weather Read more

The scientists said changes in the position of the jet stream and the circulation of air over the continent caused the droughts, and that climate change was probably the underlying driver.

“Climate change [means] extreme conditions will become more frequent, which could be devastating for agriculture, ecosystems and societies as a whole,” said Büntgen.

Prof Mrislav Trnka, of the CzechGlobe research centre in Brno, who was part of the study team, said the sharp increase in droughts was particularly alarming for agriculture and forestry.

“Unprecedented forest dieback across much of central Europe corroborates our results,” he said.

Dr Friederike Otto, of Oxford University, said a lack of historic data often hindered the clear identification of the drivers of observed events, making the new work important and useful.

“It corroborates from a long-term perspective that the huge increase in heat extremes observed over Europe in the summer, which has clearly been attributed to human-induced climate change, does indeed change the nature of summer in Europe,” she said.

The study, which was published in the journal Nature Geoscience, analysed 27,000 growth rings from 147 oak trees. Living oaks were used for the last century, then timber from old buildings such as churches. For the middle ages, the researchers used oak that had been preserved in river deposits or gravel beds, and for the Roman period they used remains such as wood used to construct wells.

Previous climate reconstructions from tree rings used width and wood density to determine temperature.

The Büntgen-led study used measurements of carbon and oxygen isotopes to show how much water was available to the trees, giving a record of droughts. This showed that the high frequency of recent European droughts was unprecedented, even compared with severe historical droughts such as the Renaissance drought in the early 16th century.

The wood samples come from the Czech Republic and Bavaria in Germany, and represent climate conditions across central Europe. High temperatures were the main cause of recent droughts, and these have been seen across Europe.

The climate crisis is also linked to extreme wet weather in winter. The rainfall in the UK on 3 October 2020 was the highest in records dating back to 1891, and a study published last Wednesday said this had been made three times more likely by global heating.

The research by the UK Met Office also found that such downpours will be 10 times more likely by 2100 without major cuts to carbon emissions.

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(AU) Sydney Plans Tree-Planting Blitz To Curb Heat

Sydney Morning Herald - Peter Hannam

The City of Sydney will spend $377 million over the next decade to boost tree cover, including nudging residents to plant more vegetation, in a bid to counter the effects of a warming climate.

The city’s council will unveil its Greening Sydney 2030 plan on Wednesday, which details how it will raise the area’s canopy cover from 18 per cent in 2019 to 27 per cent by 2050.

About 700 trees will be added each year to parks, lanes, roads and parks to boost shade and reduce the city’s so-called heat-island effect. Heat maps already reveal stark differences in temperatures.

“We’re in the middle of a climate crisis and we are already experiencing its impacts. Dangerous heatwaves are arriving earlier, are hotter and last longer,” Lord Mayor Clover Moore said. “Our city must adapt to the changing climate and increase its resilience to the likely impacts.”

The council’s urban forest manager Karen Sweeney said the challenge would be adding trees where possible, especially on private property.

“We know where the hotspots are and where we can make the difference,” Ms Sweeney said. “The larger the green area, the more benefits you have.”

Private land, which accounts for about 60 per cent of the local government area, now has about 12 per cent canopy cover. The goal is to lift the share by about two-thirds to 20 per cent by mid-century.

Another challenge is to increase access across the city to green spaces to improve equity.

“You can’t benefit from shade 10 kilometres away,” Ms Sweeney said.

The City of Sydney’s plan dovetails with the state government’s $10 million effort to plant 1 million trees across the city by 2022. The halfway mark in that program for Greater Sydney was reached last week with the 500,000th tree planted by Planning Minister Rob Stokes in Bungarribee Park in western Sydney.

The City of Sydney is aiming to lift the amount of tree cover from about 18 per cent now to 27 per cent by mid-century as part of its effort to reduce the heat-island effect and bring other benefits to residents. Credit: Peter Rae

The City of Sydney’s population increased by about a quarter, or 67,000 people, over the past decade, and is projected to swell by another 115,000 by 2036. The rising number of residents will add pressure to existing green spaces. Westconnex and other large projects are also cutting into greenery.

The target will be met in part by planting trees in areas that have not seen them for many years, while “green roofs provide another option”, Ms Sweeney said.

Temperatures in the shade can be hot, but those in the sun, such as Bondi Beach in November 2015, weren't far off 60 degrees, according to heat cameras. Credit: Nick Moir

While native tree species will be preferred they may not necessarily be typical Sydney trees.

Sydney’s climate, where days average about 22.7 degrees across the year and 26.7 degrees in summer, is forecast to shift by 2050 to be more like the climate of Grafton. The northern NSW town now averages 25.5 degrees across the year and 29.4 degrees during summer.

Some of the areas earmarked for more trees may, though, be planted with deciduous exotic species, particularly if residents’ solar panels would probably be affected by excessive shade.

“Certainly we’ll ask for community input to get the balance right,” Ms Sweeney said.

The greening plan, to be revealed on Wednesday, will then go on public exhibition to receive feedback for five weeks, with an aim to have it approved by council in July.

The worst natural disasters of 2020

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(AU) Experts Urge Governments To Follow Health Advice On Climate, As They Did With Covid

RenewEconomy - Michael Mazengarb

Leading Australian health practitioners, including former chief medical officers, have called on the Morrison government to prepare a new ‘National Strategy on Climate Change, Health and Well-being’, saying governments should listen to health experts, just as they did for the Covid-19 pandemic.

A group of 30 health professionals gathered at Parliament House in Canberra on Tuesday to issue the joint call to the Morrison government, saying that climate change represented an “urgent” health emergency that required a coordinated response.

Among the health professionals who travelled to Canberra were two former state chief health officers, whose currently serving contemporaries have played a central role in guiding the response to the Covid-19 pandemic.

Former Queensland chief health officer emeritus professor Gerard FitzGerald, who served in the position between 2003 and 2005, said the Morrison government should be heeding the advice of health experts when it came to climate change, in the same way it has informed its response to the pandemic.

“Politicians have turned to Chief Health Officers to steer them through the COVID-19 health emergency. Today we are asking them to keep listening to the advice of leading health voices and swiftly act on the health emergency of climate change,” FitzGerald said.

Former Tasmanian chief health officer Dr Roscoe Taylor, who retired from the position in 2015, said that it was becoming increasingly clear that climate change posed a significant threat to the health and well-being of Australians as its impacts worsened.

“Over my 30 years working in public health, I have witnessed the rising harms and costs of climate change. Unless all governments, and particularly the federal government, takes health advice seriously, the preventable harms of climate change will only worsen and more people will lose their lives or suffer ill-health,” Taylor said.

The calls have been coordinated by the Climate and Health Alliance, a peak body that represents a range of professional health associations, and which describes the growing impacts of climate change as an “urgent health emergency.”

The alliance published a framework for creating a National Strategy on Climate Change, Health and Well-being in 2017, based on consultation with a wide range of health experts, which found there was a lack of leadership at a federal level on responding to the worsening health impacts being caused by climate change.

“Health leaders have come to Parliament today to urge politicians to recognise climate change is a health emergency that requires their urgent action,” Climate and Health Alliance Executive Director Fiona Armstrong said.

“Health leaders don’t use the term ’emergency’ lightly. Across the country, doctors, nurses and health practitioners are already treating the health impacts caused by worsening climate change.

“We call on all Parliamentarians to support developing a National Strategy on Climate, Health and Well-being in order to protect our health and secure the many health benefits associated with climate action,” Armstrong added.

Australian Greens moved a motion in the federal senate on Tuesday, calling for the development by the government of a “National Strategy on Climate Change, Health and Well-being,” in line with the recommendations of the Climate and Health Alliance and the health experts who visited parliament.

The motion was passed by the senate, without opposition from government senators.

A Harvard led research study published in February estimated that as many as 8.7 million people died in a single year as a result of fossil fuel linked pollution, triggered primarily by air pollution.

Last year, a group of scientists, researchers, and medical professionals published research that suggested as many as 800 people suffered premature deaths each year directly as a result of pollution from coal-fired power stations.

According to the world health organisation, an estimated 2.65 million people have died as a result of the Covid-19 pandemic, including 909 who have died in Australia.

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