Lethal Heating: 10/11/20

11/10/2020

(AU) Act Now On Wildfires, Global Climate Change, Human Health, Study Says

Mirage News - Monash University

Immediate actions are needed to limit the greenhouse gas emissions that are driving climate change that helps fuel wildfires, a Monash University study says.

Change In Length Wildfire Season

A future scenario of high greenhouse-gas emissions and no climate change–mitigation policy, with an increase in the global mean surface temperature of 2.2°C to 4.4°C relative to the 2019 level.

A special report published in the New England Journal of Medicine, led by Professor Yuming Guo and Dr Shanshan Li from the Monash School of Public Health and Preventive Medicine, summarises the enormous impacts of climate change on wildfire seasons and the sequential increased morbidity, mortality, and mental health impacts.

The report, which analysed numerous studies on wildfires over the past 20 years, says global climate change is fueling the three essential conditions for wildfires – fuel, oxygen and an ignition source. The world is seeing inconsistent rainfall, increased drought and hotter temperatures, leading to more flammable vegetation.

It says the global mean carbon dioxide (CO2) emissions from wildfires accounted for about 22 per cent of the carbon emission from burning fossil fuels between 1997-2016. The inconsistent approach to global forest management and the conversion of tropical savannas to agricultural lands is damaging the world’s ability to absorb CO2 and cool the climate.

The report says projections suggest that if high greenhouse gas emissions continue, wildfire exposure could substantially increase to over 74 per cent of the global land mass by the end of the century.

However, if immediate climate mitigation efforts are taken to limit the global mean temperature increase to 2.0˚C or 1.5˚C, a corresponding 60 per cent and 80 per cent, respective increase in wildfire exposure could be avoided, the report says.

Reaching the 1.5°C target would require reducing global net CO2 emissions by about 45 per cent from 2010 levels by 2030 and reaching net zero around 2050. The 1.5°C target remains achievable if CO2 emissions decline by 7.6 per cent per year from 2020 to 2030.

The report says the devastating health impacts are illustrated by several large and – in some cases – unprecedented recent wildfires. These include the 2019-2020 Australian wildfires, the 2019 and 2020 Amazon fires in Brazil, the 2018 and 2020 wildfires in the western US, the 2017-2018 wildfires in British Columbia, Canada, and the ongoing record-breaking wildfires on the US West Coast.

Along with the increased eye irritation, corneal abrasions and respiratory impacts of the smoke, the psychological effects are equally as serious with post-traumatic stress disorder (PTSD), depression, and insomnia common. The psychological consequences of wildfire events can persist for years, with children and adolescents particularly vulnerable.

A 20-year study on adults exposed to an Australian bushfire disaster as children in 1983 found an increase in psychiatric morbidity in adulthood, with wildfire events associated with subsequent reductions in children’s academic performance.

The report says the current exchange between wildfires and climate change is likely to form a reinforcing feedback loop, making wildfires and their health consequences increasingly severe, unless we can come together to reduce greenhouse gas emissions.

Instrumental to this study was the collaboration with Xu, Rongbin, Yu, Pei, Abramson, Michael from Monash University, School of Public Health and Preventive Medicine; Johnston, Fay; Menzies Institute for Medical Research, University of Tasmania; Samet, Jonathan; Colorado School of Public Health; Bell, Michelle; Yale University, School of Forestry and Environmental Studies, Haines, Andy; London School of Hygiene and Tropical Medicine, Public Health, Environments and Society Ebi, Kristie; University of Washington School of Public Health, Department of Global Health.

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Climate Change: How Do We Know?

NASA Global Climate Change

Earth's climate has changed throughout history. Just in the last 650,000 years there have been seven cycles of glacial advance and retreat, with the abrupt end of the last ice age about 11,700 years ago marking the beginning of the modern climate era — and of human civilization.

Most of these climate changes are attributed to very small variations in Earth’s orbit that change the amount of solar energy our planet receives.

Scientific evidence for warming of the climate system is unequivocal.
- Intergovernmental Panel on Climate Change

The current warming trend is of particular significance because most of it is extremely likely (greater than 95% probability) to be the result of human activity since the mid-20^th century and proceeding at a rate that is unprecedented over decades to millennia.

Earth-orbiting satellites and other technological advances have enabled scientists to see the big picture, collecting many different types of information about our planet and its climate on a global scale. This body of data, collected over many years, reveals the signals of a changing climate.

This graph, based on the comparison of atmospheric samples contained in ice cores and more recent direct measurements, provides evidence that atmospheric CO₂ has increased since the Industrial Revolution. (Credit: Luthi, D., et al.. 2008; Etheridge, D.M., et al. 2010; Vostok ice core data/J.R. Petit et al.; NOAA Mauna Loa CO₂ record.) Find out more about ice cores (external site).

The heat-trapping nature of carbon dioxide and other gases was demonstrated in the mid-19th century. Their ability to affect the transfer of infrared energy through the atmosphere is the scientific basis of many instruments flown by NASA. There is no question that increased levels of greenhouse gases must cause Earth to warm in response.

Ice cores drawn from Greenland, Antarctica, and tropical mountain glaciers show that Earth’s climate responds to changes in greenhouse gas levels. Ancient evidence can also be found in tree rings, ocean sediments, coral reefs, and layers of sedimentary rocks.

This ancient, or paleoclimate, evidence reveals that current warming is occurring roughly ten times faster than the average rate of ice-age-recovery warming. Carbon dioxide from human activity is increasing more than 250 times faster than it did from natural sources after the last Ice Age.

The evidence for rapid climate change is compelling

Global Temperature Rise
The planet's average surface temperature has risen about 2.05 degrees Fahrenheit (1.14 degrees Celsius) since the late 19th century, a change driven largely by increased carbon dioxide and other human-made emissions into the atmosphere. Most of the warming occurred in the past 40 years, with the six warmest years on record taking place since 2014. Not only was 2016 the warmest year on record, but eight months out of that year — from January through September, with the exception of June — were the warmest on record for those respective months.

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Warming Ocean
The ocean has absorbed much of this increased heat, with the top 100 meters (about 328 feet) of ocean showing warming of more than 0.6 degrees Fahrenheit (0.33 degrees Celsius) since 1969. Earth stores 90% of the extra energy in the ocean.

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Image: Flowing meltwater from the Greenland ice sheet

Shrinking Ice Sheets
The Greenland and Antarctic ice sheets have decreased in mass. Data from NASA's Gravity Recovery and Climate Experiment show Greenland lost an average of 279 billion tons of ice per year between 1993 and 2019, while Antarctica lost about 148 billion tons of ice per year.

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Image: The disappearing snowcap of Mount Kilimanjaro, from space.

Glacial Retreat
Glaciers are retreating almost everywhere around the world — including in the Alps, Himalayas, Andes, Rockies, Alaska, and Africa.

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Interactive: Global ice viewer

Decreased Snow Cover
Satellite observations reveal that the amount of spring snow cover in the Northern Hemisphere has decreased over the past five decades and the snow is melting earlier.

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Image: Republic of Maldives: Vulnerable to sea level rise

Sea Level Rise
Global sea level rose about 8 inches (20 centimeters) in the last century. The rate in the last two decades, however, is nearly double that of the last century and accelerating slightly every year.

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Image: Visualization of the 2012 Arctic sea ice minimum, the lowest on record

Declining Arctic Sea Ice
Both the extent and thickness of Arctic sea ice has declined rapidly over the last several decades.

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Extreme Events
The number of record high temperature events in the United States has been increasing, while the number of record low temperature events has been decreasing, since 1950. The U.S. has also witnessed increasing numbers of intense rainfall events.

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Ocean Acidification
Since the beginning of the Industrial Revolution, the acidity of surface ocean waters has increased by about 30%. This increase is the result of humans emitting more carbon dioxide into the atmosphere and hence more being absorbed into the ocean. The ocean has absorbed between 20% and 30% of total anthropogenic carbon dioxide emissions in recent decades (7.2 to 10.8 billion metric tons per year).

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(AU) Financial System Faces 'Considerable' Risk If Climate Change Not Tackled: RBA

Sydney Morning Herald - Jennifer Duke

The Reserve Bank has warned both climate change and lowering emissions pose considerable risk to financial stability while regulators assessing the threat have been delayed by the nation's worst recession since World War II.

The central bank laid out a list of concerns about the future resilience of the global economy in a financial stability report released on Friday morning, describing climate change as an "ongoing challenge for the financial system".

The RBA has warned about considerable risks from climate change. Credit: Peter Braig

"Climate change is exposing financial institutions, and the financial system more broadly, to risks that will rise over time and, if not addressed, could become considerable," the report said. "These risks for financial stability may arise from both the physical and transition risks of climate change."

The report said the financial system was generally resilient, but there were pre-existing risks including several common to institutions across the world such as cyber risks from criminal and state-sponsored groups and long-term risks from climate change.

"Addressing these [climate change risks] early will help to both mitigate the transition risks and reduce the scale of the challenge that physical risk poses to financial stability in future."

Some of the work to address the financial risks of climate change had been delayed due to the coronavirus pandemic and its economic fallout, including assessment of risk vulnerability by the Australian Prudential Regulation Authority, but the RBA said this would be a "key focus in the period ahead".

APRA's assessment requires major banks, superannuation funds, insurers and other financial institutions to estimate the physical impact of a changing climate on their balance sheet and the risks of a global move towards lower carbon emissions.

Financial institutions with high exposure to industries like power and mining are expected to have higher transition risk as the economy moves to lower carbon. There are also risks involved in new technologies displacing emissions-intensive practices and consumers picking greener products.

The RBA warned in 2019 that if transition changes occur too abruptly this could leave some firms facing large losses and "broader dislocation in financial markets".

APRA executive board member Geoff Summerhayes said in February in a letter to all regulated entities the watchdog would provide better clarity on regulatory expectations around climate-related risks, which he said extended to all sectors of the economy.

"Those effects are being transmitted directly as well as indirectly, through changing policies, technological developments, investment and consumer preferences. They pose financial risks, as well as provide new business opportunities, to all APRA-regulated entities," Mr Summerhayes said.

A 2018 APRA climate change survey found while many larger businesses understood the financial risks and opportunities, there was an industry-wide deficit of data able to quantify the liability risks of climate change.

The RBA is part of the Network for Greening the Financial System, which in June published a set of climate scenarios to help with risk assessment. The research found climate change could "obscure the assessment of correct monetary policy settings".

The RBA's report notes the NGFS recommended "central banks strengthen their analytical tool kits and enhance their communication strategies to help accustom households, firms, governments and financial market participants to the risks of climate change for the economy and the financial system".

Major industry superannuation fund HESTA chief executive Debby Blakey wrote to Australia's top 200 listed companies in September pressuring them to commit to lowering carbon emissions in line with the Paris Agreement for net zero by 2050. Ms Blakey said that as a long-term investor the fund has "an absolute responsibility to take into account these issues".

However, Assistant Minister for Superannuation, Financial Services and Financial Technology Jane Hume has been critical of funds for forgetting "their job isn't to rebuild the economy or create jobs or reframe the climate debate or require industrial relations changes at companies they invest in".

RBA governor Philip Lowe warned in February climate change would have a "profound" impact on the economy, leaving businesses with stranded assets, and encouraged the government to protect the country from a warming environment.

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