Lethal Heating: 03/08/19

08/03/2019

Climate Change Sceptics Push To Ban Teaching Global Warming Facts

NEWS.com.au

A growing number of politicians in the US are trying to introduce laws that would allow teachers to dismiss the scientific consensus that global warming is man-made.

World leaders have been warned that civilisation could collapse

In Australia and many other countries, school students have been taking to the streets to demand their nation’s leaders take action on climate change.

But in America, perhaps in an effort to stop similar student protests, some politicians are working to introduce legislation that would allow teachers to dismiss the scientific consensus that global warming is man-made.

In Connecticut, a politician wants to strike climate change from state science standards. Meanwhile in Virginia, a legislator worries teachers are indoctrinating students with their personal views on global warming. And an Oklahoma state senator wants educators to be able to introduce alternative ideas without fear of losing their jobs.

Students gather to demand the government take action on climate change at Martin Place on November 30, 2018 in Sydney, Australia. Picture: Getty Images Source: Getty Images

Of the more than a dozen such measures proposed so far this year, some already have failed. But they have emerged this year in growing numbers, many of them inspired or directly encouraged by a pair of advocacy groups.
One group is The Heartland Institute, a conservative think-tank group based in Illinois best known for working with the tobacco company Philip Morris in the 1990s to attempt to discredit the health risks of smoking cigarettes.
The Heartland Institute does not disclose its funding sources.
Climate scientists have blasted such proposals for sowing confusion and doubt.

As climate change becomes a hotter topic in American classrooms in 2019, some politicians are pushing back against the scientific consensus that global warming is real. Picture: AP Source: AP

The efforts in North America to teach alternative theories to climate science follow high-profile protests by school students around the world.
Australian students striking for climate change want adults to join them for a global event on March 15, and organisers say they already have support from a growing number of unions.
Despite the criticism strikers copped from Prime Minister Scott Morrison for skipping classes last year, school students around Australia are planning to walk out of school again for another rally ahead of the federal election.
This time they are also urging adults to back the strike and also walk out for the day in solidarity.

Students hold a climate march at Martin Place. Picture: Jenny Evans Source: News Corp Australia

This year’s event is already being supported by a growing number of unions including the National Union of Workers, National Tertiary Education Union, United Firefighters Union, Hospo Voice, the Victorian Allied Health Professionals Association and the National Union of Students.
The National Union of Workers, one of the most powerful unions in the Labor Party and part of its right-wing faction that supports Opposition Leader Bill Shorten, said it was supporting the strike and the students standing together collectively for their future.
“They are inspiring leaders, and we support them in making our political leaders listen,” the union said.

Students demonstrate in Paris on March 1, 2019 to protest against climate change, part of a Europe-wide movement that has seen walkouts across the continent. Picture: AFP Source: AFP

More than 300 academics have also signed an open letter in solidarity with the student strikers supporting their stance against Adani’s Carmichael mine and a ban on gas mining.
The strikes created headlines last year when more than 15,000 students took the day off school to protest the lack of action on climate change, rallying in public spaces in Melbourne, Sydney and about 30 other cities and towns in Australia.
This year’s event, coming ahead of the federal election, is expected to be even bigger with organisers telling news.com.au students are extending an open invitation to everyone in the community to join them.
The school strike is gaining traction around the world. Australia’s March 15 event will also coincide with school protests in more than 40 other countries.

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Climate Change Will Expose Half Of World’s Population To Disease-Spreading Mosquitoes By 2050

Yale Environment 360

The yellowfever mosquito Aedes aegypti.

PHIL/CDC PHIL, CDC

Scientists and public health officials have documented an increasing number of outbreaks of mosquito-borne illnesses across the globe in recent years, including yellow fever, dengue, chikungunya, and Zika.
Now, an international team of researchers has found that by 2050, two key disease-spreading mosquitoes — Aedes aegypti and Aedes albopictus — will significantly expand their range, posing a threat to 49 percent of the world’s population.
“If no action is taken to reduce the current rate at which the climate is warming, pockets of habitat will open up across many urban areas with vast amounts of individuals susceptible to infection,” said Moritz Kraemer, an infectious disease scientist at Boston Children’s Hospital and the University of Oxford and a co-author of the new research, published in the journal Nature Microbiology,.
The researchers analyzed historical distribution data from more than 3,000 locations in Europe and the United States, dating back to the 1970s.
They then modelled future distribution using projections for climate change, urbanization, and human migration and travel. Kraemer and his colleagues found that in the last five years, Aedes aegypti has spread northward in the U.S. at about 150 miles per year.
In Europe, Aedes albopictus has spread at a rate of 93 miles per year.

These maps show the predicted global ranges of Aedes aegypti (above) and Aedes albopictus (below) in 2050 assuming a 'medium' climate scenario in which greenhouse gas emissions peak in 2080 and then begin to decline. The darker areas have the highest predicted prevalence of mosquitos.

Moritz Kraemer for Nature Microbiology

The scientists also found that within the next 5 to 15 years, human travel and migration will be the largest factors driving the spread of mosquitoes. After that, however, climate change and accelerating urbanization will create new mosquito habitats. Aedes aegypti could reach as far north as Chicago and Shanghai by 2050.
However, the species will likely decline in parts of the southern U.S. and Eastern Europe, which are expected to become more arid as global temperatures rise.
Aedes albopictus, on the other hand, is forecast to spread widely throughout Europe over the next 30 years, as well as establish small populations in parts of the northern U.S. and the highland regions of South America and East Africa.

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'Whole Thing Is Unravelling': Climate Change Reshaping Australia's Forests

The Guardian - Graham Readfearn

Droughts, heat waves, bushfires and rising temperatures are driving ecosystems towards collapse

Researchers have found that big eucalypts grow slower as temperatures rise thanks to climate change.
Photograph: N Cirani/De Agostini/Getty Images

Australia’s forests are being reshaped by climate change as droughts, heat waves, rising temperatures and bushfires drive ecosystems towards collapse, ecologists have told Guardian Australia. Trees are dying, canopies are getting thinner and the rate that plants produce seeds is falling. Ecologists have long predicted that climate change would have major consequences for Australia’s forests.Now they believe those impacts are unfolding.
“The whole thing is unravelling,” says Prof David Bowman, who studies the impacts of climate change and fire on trees at the University of Tasmania. “Most people have no idea that it’s even happening. The system is trying to tell you that if you don’t pay attention then the whole thing will implode. We have to get a grip on climate change.”
According to the 2018 State of the Climate Report, produced by CSIRO and the Bureau of Meteorology, large parts of the country are experiencing increases in weather patterns favourable to fires. The report found that rainfall has dropped in the south-east and south-west of the country, temperatures have warmed by an average of 1C, and a “shift to a warmer climate in Australia is accompanied by more extreme daily heat events”.
Dr Joe Fontaine, an ecologist at Murdoch University, says forests across Australia are changing. “Impacts are direct – trees dying from heat and drought – as well as indirect – more fire, fewer seeds and a raft of associated feedbacks.”
Fontaine says leaves are the “machinery that makes the plant work” and how those leaves cope with heat depends on moisture reserves. “The question then is, how much do you have in reserve? A lot of us are really concerned about that.”

Fontaine has studied one large shrub species – the south-western native Hooker’s banksia – and found seed production has “halved in the last 30 years”, which was “definitely a climate-driven problem with increased drought”.
Last spring, Fontaine and colleagues inspected an area 300km north of Perth where the banksias had been hit by fire several years earlier. He wanted to know if they could cope with fire on top of the area’s long-term reduction in rainfall.
“At this stage, years after fire, those plants should be recovering and really going for it,” he says. “Except instead these banksias weredead and falling over left and right. The young plants were dying too – this area was losing all their young vigorous plants. With more bushfire, this species is at real risk of being wiped off the map.”

The interval squeeze
A study of the impacts of a heat wave in 2010 and 2011 in the south-west that followed long-term drops in rainfall found that the the large jarrah eucalypts and the area’s giant banksias were severely affected. A knock-on effect, another study found, was that the area became even more prone to fires.
Bowman says the impacts of the changing climate are “absolutely” happening. Bowman and colleagues have found that big eucalypts grow slower as temperatures rise and alpine ash forests were at risk of being wiped out because fires were coming along too often.
This is part of a phenomenon known as the “interval squeeze” where species that are adapted to cope with drought or fire, struggle when the time between impacts gets shorter.
Bowman says the idea that Australia’s forests are well adapted to the country’s variable climate and can withstand fire and drought, was incorrect. “A big misapprehension is that these things are climatologically flexible, but they’re just not,” he says, explaining that Australia’s dominant eucalypts have “fine-tuned their life history around assumptions of fire frequency”, but “climate change is just blowing that up”.
“All this is non-linear,” he says. “What will happen is the system will crash faster than we realise. Yes, it will reassemble and there will be forests, but they won’t look anything like what we have now. We are going to see this transformation before our eyes.”

Predicting the future?
The climate change impacts are not only restricted to old-growth forests – the changing climate is also causing problems for groups trying to reforest areas that have been previously cleared.
Usually, revegetation projects will gather seeds from the local area to sow or propagate in a practice known as provenance planting.
But two major groups are using climate projection tools to second-guess the changes in rainfall and heat expected in the areas where they are planting.
Landcare Australia and Bush Heritage Australia have started to source seeds from places that better match the climate conditions in coming decades.
Dr Matt Appleby, a senior ecologist at Bush Heritage Australia, says that in about 2014, the group began to see dead patches in a replanting project at Nardoo Hills in Victoria, and the problem worsened each year.
“We had a heat wave back in 2014 with about a week of temperatures well over 40C and that was combined with already low soil moisture,” he says. “We think that combination meant the trees were under so much stress they reach a critical point and were dying.”
Now the group has started a climate-ready revegetation project for the reserve. Even among the same species of tree, there can be subtle genetic variations that give the same species different tolerances depending on where they are growing.
The group has used climate tools to find areas in the country known as “climate analogues” that match the hotter and drier conditions expected at Nardoo.
“We are collecting seeds from those locations and bringing them to Nardoo Hills to propagate and plant out,” Appleby says. What happens then is that in 20 years the seeds of those plants will be better adapted to the area – they should have that little bit more resilience.”
Appleby is concerned the job of gathering seeds for rarer species could get more difficult. “Trying to get seed this past year has been incredibly difficult. What happens if in five years’ time we get a run of 49C days?” he says.
“How are we going to get seed then if everything is under pressure? People need to start thinking about seed banks and seed production areas so there’s enough seed down the track to sustain this.”
Dr Shane Norrish, the chief executive of Landcare Australia, says like many other organisations carrying out major revegetation works, climate change was presenting a challenge. For one major revegetation project at Dakalanta on the Eyre peninsula, Landcare Australia has also used this “climate-ready” approach when sourcing some of their seeds.
“What you will never be able to deal with is the run of extreme hot days that we’ve experienced in southern Australia – that level of extreme variability challenges everyone.”

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