EXPERT REACTION: Climate change has not stopped for COVID-19 (United in Science 2020 Report)

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Climate change has not stopped for COVID-19, say the authors of this year's United in Science Report, which presents the very latest data and findings related to climate change to inform global policy and action. Greenhouse gas concentrations in the atmosphere are at record levels and continue to increase. Emissions are heading in the direction of pre-pandemic levels following a temporary decline caused by the lockdown and economic slowdown. The world is set to see its warmest five years on record – in a trend which is likely to continue - and is not on track to meet agreed targets to keep global temperature increase well below 2 °C or at 1.5 °C above pre-industrial levels.

Journal/conference: World Meteorological Organization (WMO)

Organisation/s: World Meteorological Organization (WMO), CSIRO, Macquarie University, The University of Adelaide, Monash University, The University of Tasmania

Funder: N/A

Media release

From: World Meteorological Organization (WMO)

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United in Science report: Climate Change has not stopped for COVID19

New York/Geneva - Climate change has not stopped for COVID19. Greenhouse gas concentrations in the atmosphere are at record levels and continue to increase. Emissions are heading in the direction of pre-pandemic levels following a temporary decline caused by the lockdown and economic slowdown. The world is set to see its warmest five years on record – in a trend which is likely to continue - and is not on track to meet agreed targets to keep global temperature increase well below 2 °C or at 1.5 °C above pre-industrial levels.
This is according to a new multi-agency report from leading science organizations, United in Science 2020. It highlights the increasing and irreversible impacts of climate change, which affects glaciers, oceans, nature, economies and human living conditions and is often felt through water-related hazards like drought or flooding. It also documents how COVID-19 has impeded our ability to monitor these changes through the global observing system.
“This has been an unprecedented year for people and planet. The COVID-19 pandemic has disrupted lives worldwide. At the same time, the heating of our planet and climate disruption has continued apace,” said UN Secretary-General António Guterres in a foreword.
“Never before has it been so clear that we need long-term, inclusive, clean transitions to tackle the climate crisis and achieve sustainable development. We must turn the recovery from the pandemic into a real opportunity to build a better future,” said Mr Guterres, who will present the report on 9 September. “We need science, solidarity and solutions.”
The United in Science 2020 report, the second in a series, is coordinated by the World Meteorological Organization (WMO), with input from the Global Carbon Project, the Intergovernmental Panel on Climate Change, the Intergovernmental Oceanographic Commission of UNESCO, the UN Environment Programme and the UK Met Office. It presents the very latest scientific data and findings related to climate change to inform global policy and action.
“Greenhouse gas concentrations - which are already at their highest levels in 3 million years - have continued to rise. Meanwhile, large swathes of Siberia have seen a prolonged and remarkable heatwave during the first half of 2020, which would have been very unlikely without anthropogenic climate change. And now 2016–2020 is set to be the warmest five-year period on record. This report shows that whilst many aspects of our lives have been disrupted in 2020, climate change has continued unabated,” said WMO Secretary-General, Professor Petteri Taalas.
Greenhouse Gas Concentrations in the Atmosphere (World Meteorological Organization)
Atmospheric CO2 concentrations showed no signs of peaking and have continued to increase to new records. Benchmark stations in the WMO Global Atmosphere Watch (GAW) network reported CO2 concentrations above 410 parts per million (ppm) during the first half of 2020, with Mauna Loa (Hawaii) and Cape Grim (Tasmania) at 414.38 ppm and 410.04 ppm, respectively, in July 2020, up from 411.74 ppm and 407.83 ppm in July 2019.
Reductions in emissions of CO2 in 2020 will only slightly impact the rate of increase in the atmospheric concentrations, which are the result of past and current emissions, as well as the very long lifetime of CO2. Sustained reductions in emissions to net zero are necessary to stabilize climate change.
Global Fossil CO2 emissions (Global Carbon Project)
CO2 emissions in 2020 will fall by an estimated 4% to 7% in 2020 due to COVID-19 confinement policies. The exact decline will depend on the continued trajectory of the pandemic and government responses to address it.
During peak lockdown in early April 2020, the daily global fossil CO2 emissions dropped by an unprecedented 17% compared to 2019. Even so, emissions were still equivalent to 2006 levels, highlighting both the steep growth over the past 15 years and the continued dependence on fossil sources for energy.
By early June 2020, global daily fossil CO2 emissions had mostly returned to within 5% (1%–8% range) below 2019 levels, which reached a new record of 36.7 Gigatonnes (Gt) last year, 62% higher than at the start of climate change negotiations in 1990.
Global methane emissions from human activities have continued to increase over the past decade. Current emissions of both CO2 and methane are not compatible with emissions pathways consistent with the targets of the Paris Agreement.
Emissions Gap (UN Environment Programme)
Transformational action can no longer be postponed if the Paris Agreement targets are to be met.
The Emissions Gap Report 2019 showed that the cuts in global emissions required per year from 2020 to 2030 are close to 3% for a 2 °C target and more than 7% per year on average for the 1.5 °C goal of the Paris Agreement.
The Emissions Gap in 2030 is estimated at 12-15 Gigatonnes (Gt) CO2e to limit global warming to below 2 °C. For the 1.5 ° C goal, the gap is estimated at 29-32 Gt CO2e, roughly equivalent to the combined emissions of the six largest emitters.
It is still possible to bridge the emissions gap, but this will require urgent and concerted action by all countries and across all sectors. A substantial part of the short-term potential can be realized through scaling up existing, well-proven policies, for instance on renewables and energy efficiency, low carbon transportation means and a phase out of coal.
Looking beyond the 2030 timeframe, new technological solutions and gradual change in consumption patterns are needed at all levels. Both technically and economically feasible solutions already exist.
State of Global Climate (WMO and UK’s Met Office)
The average global temperature for 2016–2020 is expected to be the warmest on record, about 1.1 °C above 1850-1900, a reference period for temperature change since pre-industrial times and 0.24°C warmer than the global average temperature for 2011-2015.
In the five-year period 2020–2024, the chance of at least one year exceeding 1.5 °C above pre-industrial levels is 24%, with a very small chance (3%) of the five-year mean exceeding this level. It is likely (~70% chance) that one or more months during the next five years will be at least 1.5 °C warmer than pre-industrial levels.
In every year between 2016 and 2020, Arctic sea ice extent has been below average. 2016–2019 recorded a greater glacier mass loss than all other past five-year periods since 1950. The rate of global mean sea-level rise increased between 2011–2015 and 2016–2020.
Major impacts have been caused by extreme weather and climate events. A clear fingerprint of human-induced climate change has been identified on many of these extreme events. 
The Ocean and Cryosphere in a Changing Climate (Intergovernmental Panel on Climate Change)
Human-induced climate change is affecting life-sustaining systems, from the top of the mountains to the depths of the oceans, leading to accelerating sea-level rise, with cascading effects for ecosystems and human security.
This increasingly challenges adaptation and integrated risk management responses.
Ice sheets and glaciers worldwide have lost mass. Between 1979 and 2018, Arctic sea-ice extent has decreased for all months of the year. Increasing wildfire and abrupt permafrost thaw, as well as changes in Arctic and mountain hydrology, have altered the frequency and intensity of ecosystem disturbances.
The global ocean has warmed unabated since 1970 and has taken up more than 90% of the excess heat in the climate system. Since 1993 the rate of ocean warming, and thus heat uptake has more than doubled. Marine heatwaves have doubled in frequency and have become longer-lasting, more intense and more extensive, resulting in large-scale coral bleaching events. The ocean has absorbed between 20% to 30% of total anthropogenic CO2 emissions since the 1980s causing further ocean acidification.
Since about 1950 many marine species have undergone shifts in geographical range and seasonal activities in response to ocean warming, sea-ice change and oxygen loss.
Global mean sea-level is rising, with acceleration in recent decades due to increasing rates of ice loss from the Greenland and Antarctic ice sheets, as well as continued glacier mass loss and ocean thermal expansion. The rate of global mean sea-level rise for 2006–2015 of 3.6 ±0.5 mm/yr is unprecedented over the last century
Climate and Water Resources (WMO)
Climate change impacts are most felt through changing hydrological conditions including changes in snow and ice dynamics.
By 2050, the number of people at risk of floods will increase from its current level of 1.2 billion to 1.6 billion. In the early to mid-2010s, 1.9 billion people, or 27% of the global population, lived in potential severely water-scarce areas. In 2050, this number will increase to 2.7 to 3.2 billion people.
As of 2019, 12% of the world population drinks water from unimproved and unsafe sources. More than 30% of the world population, or 2.4 billion people, live without any form of sanitation.
Climate change is projected to increase the number of water-stressed regions and exacerbate shortages in already water-stressed regions.
The cryosphere is an important source of freshwater in mountains and their downstream regions. There is high confidence that annual runoff from glaciers will reach peak globally at the latest by the end of the 21st century. After that, glacier runoff is projected to decline globally with implications for water storage.
It is estimated that Central Europe and Caucasus have reached peak water now, and that the Tibetan Plateau region will reach peak water between 2030 and 2050. As runoff from snow cover, permafrost and glaciers in this region provides up to 45% of the total river flow, the flow decrease would affect water availability for 1.7 billion people.
Earth System Observations during COVID-19 (Intergovernmental Oceanographic Commission of UNESCO and WMO)
The COVID-19 pandemic has produced significant impacts on the global observing systems, which in turn have affected the quality of forecasts and other weather, climate and ocean-related services.
The reduction of aircraft-based observations by an average of 75% to 80% in March and April degraded the forecast skills of weather models. Since June, there has been only a slight recovery. Observations at manually operated weather stations, especially in Africa and South America, have also been badly disrupted.
For hydrological observations like river discharge, the situation is similar to that of atmospheric in situ measurements. Automated systems continue to deliver data whereas gauging stations that depend on manual reading are affected.
In March 2020, nearly all oceanographic research vessels were recalled to home ports. Commercial ships have been unable to contribute vital ocean and weather observations, and ocean buoys and other systems could not be maintained. Four full-depth ocean surveys of variables such as carbon, temperature, salinity, and water alkalinity, completed only once per decade, have been cancelled. Surface carbon measurements from ships, which tell us about the evolution of greenhouse gases, also effectively ceased.
The impacts on climate change monitoring are long-term. They are likely to prevent or restrict measurement campaigns for the mass balance of glaciers or the thickness of permafrost, usually conducted at the end of the thawing period. The overall disruption of observations will introduce gaps in the historical time series of Essential Climate Variables needed to monitor climate variability and change and associated impacts.

Expert Reaction

These comments have been collated by the Science Media Centre to provide a variety of expert perspectives on this issue. Feel free to use these quotes in your stories. Views expressed are the personal opinions of the experts named. They do not represent the views of the SMC or any other organisation unless specifically stated.

Ian Lowe is Emeritus professor of science, technology and society at Griffith University, Qld and former President of the Australian Conservation Foundation.

This document is an urgent wake-up call. It shows that the global pandemic has slowed the growth in greenhouse gas emissions, but the overall trajectory is still going up. Whether we look at temperatures, rainfall patterns, ice cover or extreme events, the pattern of accelerating climate change is alarming. The average global temperature is already 1.1 degrees above the pre-industrial level and it has been calculated that there is a 70 per cent chance of monthly averages more than 1.5 degrees above the pre-industrial level before 2024.

These reports highlight “the enormous challenge facing the global community” if we are to prevent catastrophic climate change. They demonstrate that “achieving the temperature goals of the Paris Agreement...will require urgent and concerted action by all countries”.

This surely means that it is now indefensible to behave as if slowing climate change is a luxury, an optional extra if it doesn’t slow economic growth. More than 700 local authorities and several countries accept that we have “a climate emergency” that demands the “urgent and concerted action” now called for. So opening new coal provinces like the Galilee Basin, or expanding production of other fossil fuels such as coal seam gas, are acts of criminal irresponsibility. As well as curbing exports of fossil fuels and cleaning up electricity supply by investing in renewables, we desperately need a coordinated approach to our release of greenhouse gases, with particular attention to transport, agriculture and manufacturing. Like all other countries, we must take “urgent and concerted action”.

Last updated: 14 Sep 2020 10:14am
Declared conflicts of interest:
None declared.
Dr Arnagretta Hunter is a physician and cardiologist and is the Human Futures Fellow at ANU

The United in Science report offers us remarkable perspective on the growing challenge of our warming world. The health effects of climate change are a central reason to listen to this expert report. The global increase in temperatures, rise in extreme weather events will have a growing effect on our health. Climate change remains a central health challenge for the 21st century. This report should inspire leaders around the world, and particularly in Australia toward rapid decarbonisation. Time is of the essence. It is past time for all policy makers to take this seriously.

Last updated: 09 Sep 2020 7:01pm
Declared conflicts of interest:
None declared.
Professor Tom Wigley is an ARC Discovery Outstanding Researcher Awards Fellow at the University of Adelaide, formerly a Senior Scientist at the National Center for Atmospheric Research in Boulder, Colorado, and, before that, the Director of the Climatic Research Unit at the University of East Anglia. His speciality is the science of climate change, primarily data analysis, climate modeling, and issues related to what is referred to as “detection and attribution”. He has contributed to previous IPCC reports.

This Report updates many of the key issues surrounding the global warming problem, mostly through 2019. There are no surprises, and the planet is still heading rapidly towards surpassing the warming targets prescribed in the Paris Agreement.

Emissions of carbon dioxide (CO2) from fossil-fuel burning continue to rise, reaching an estimated 10 GtC in 2019 (36.7 GtCO2).

The economic disruption caused by the corona virus has reduced the trend slightly, but its multi-year effects are likely to be small.

CO2 concentrations have been rising more rapidly recently, an average of 2.5 ppm per year over 2012 through 2018, compared to an average of 2.0 ppm/yr for the 15 years preceding 2012.

Methane and nitrous oxide, the next two most important greenhouse gases, are still rising reaching record levels in 2019. Global-mean temperature over the past 5 years has reached 1.1 degC relative to the 1850-1900 pre-industrial level, sea level continues rise … at a rate more than double the rate observed over 1901-90 … mainly due to ice loss in Greenland and the Antarctic … most of the world’s mountain glaciers are retreating, and Arctic sea ice area still continues to decrease (echoed now in the Antarctic).

The Report, however, is not without flaws.

The so-called “emissions gap” is discussed, but there is apparently no realization of the complexity of this issue. The “gap” concept rests on the idea that we have a finite total emissions budget that we are in danger of surpassing soon.

The Report, however, fails to point out that the budget idea breaks down if the future trajectory of emissions has an overshoot period. An overshoot (hopefully followed by a sustained decrease in emissions) is becoming more and more likely as time passes. While there are risks associated with an overshoot, such as passing crucial “tipping points”, the good news is that this would allow a much larger budget.

The second major flaw is this: the Report is clear that “all (mitigation) options need to be brought into play”, but fails to mention the role of clean, reliable nuclear energy; and, while efficiency of energy production is mentioned, the role of increased efficiency of energy usage is not. Sadly, for the nuclear issue at least, this reflects both institutional bias, and personal biases in some of the Report’s authors.

Last updated: 09 Sep 2020 6:48pm
Declared conflicts of interest:
None declared.
Dr Pep Canadell, CSIRO Research Scientist, and Executive Director of the Global Carbon Project

The findings of the report are yet again another reminder that while we are busy finding ways out of the COVID-19 crisis and still analysing what went wrong in the last fire season, climate change continues to build the foundation of what will be the biggest ever global crisis if we don’t do more to mitigate it, and quickly.

There is a one in four chance that the global mean annual temperature will exceed 1.5°C above pre-industrial levels for at least one year over the coming five years. That is, in less than eight years since the Paris Agreement entered into force we might be touching that first critical threshold of 1.5°C, which 189 countries committed not to cross.

Last updated: 09 Sep 2020 6:42pm
Declared conflicts of interest:
None declared.
Dr Thomas Mortlock is a Senior Risk Scientist at Risk Frontiers, and Adjunct Fellow in the Department of Environmental Sciences at Macquarie University

CO2 emissions have declined in 2020 due to reduced economic activity associated with COVID-19, but this has not led to any reduction in the total amount of CO2 in the atmosphere. Studies into the Earth’s past suggest that we are presently well outside the natural range of atmospheric CO2. The last time we were at these levels was 2 - 4 million years ago. 

Even if it were possible to eliminate all CO2 emissions tomorrow, the effects on global temperature would not be felt for decades to come because of inertia in the climate system. For this reason, we need to be considering climate change in investment decisions today because it is 'baked in' for the coming decades at least.

Risk Frontiers, a catastrophe modelling company in Sydney, is translating possible future carbon emission scenarios to business impacts. This translation is critical for investors to understand future climate-related risks and further reinforces the need to reduce emissions.

Last updated: 09 Sep 2020 6:41pm
Declared conflicts of interest:
None declared.
Dr Eva Plaganyi is a Principal Research Scientist at CSIRO Oceans and Atmosphere, Brisbane, and she leads a number of research teams

The United in Science 2020 report provides a timely overview of the dangerous trajectory our planet is headed.

Globally, we are wholly unprepared for higher temperatures, more drought and floods, melting ice sheets and rising sea levels threatening coastal and island communities such as Torres Strait Islanders.

The COVID-19 pandemic has been tough on everyone but should be a wake-up call that future planetary shocks are best avoided through urgent global co-ordinated action, particularly to reduce the Emissions Gap.

The report makes clear that although there were some declines in CO2 emissions due to reduced economic activity, we need sustained reductions to help close the gap.

The report notes that the period 2016-2020 is expected to be the warmest on record and the harsh evidence is already playing out right around Australia, as fisheries and coastal systems are increasingly being negatively impacted, from corals bleaching on the Great Barrier Reef to foundation species such as mangroves and kelp dying at an alarming rate.

Based on the latest and best scientific inputs, the results of this report are sobering indeed and a key recommendation that needs to be heard is to “build back better” as we reflect on the global COVID-19 pandemic

Last updated: 09 Sep 2020 6:40pm
Declared conflicts of interest:
Eva has not declared any conflicts of interest, but notes that two of the report authors are from the CSIRO.
Dr Christine Hosking is a Conservation Planner and Researcher at the University of Queensland

Australia’s koalas are in serious trouble, and have been for many decades. This was originally primarily due to land clearing. A koala simply cannot survive without its forest.

In 2012 we predicted, using CSIRO MK 3.5 A1FI future climate models, that the koala and its food trees would experience significant range contractions as climate change progressed, pushing them towards the east coast of Australia, where ongoing population growth and urbanisation make it almost impossible for koalas to survive. 

The United Science in 2020 Report validates what Australia’s koala researchers are seeing in real time; drought, heatwaves, and bushfires are now acting in synergy with habitat loss to produce dire consequences for many koala populations, and many other unique Australian species that share the same habitat.

Last updated: 09 Sep 2020 6:39pm
Declared conflicts of interest:
None declared.
Dr Zoë Loh is a Senior Research Scientist at the CSIRO Climate Science Centre

The United in Science 2020 Report reiterates the consistent findings of the World Meteorological Organization (WMO) Global Atmosphere Watch program that atmospheric concentrations of the three most significant long-lived greenhouse gases (carbon dioxide, methane and nitrous oxide; CO2, CH4 and N2O) continue to rise at significant and accelerating rates. The growing burden of these trace gases in the atmosphere continues to drive and accelerate climate impacts across the Earth system.

The Cape Grim Baseline Air Pollution Station (NW Tasmania) provides the principal data for tracking atmospheric composition change in the Southern Hemisphere. Observations at Cape Grim, highlighted in the Report, show that the CO2 concentration at Cape Grim reached 410.04 ppm in July 2020; an increase of 2.21 ppm since July 2019.

Despite reductions in fossil fuel CO2 emissions associated with measures to inhibit the spread of COVID-19, atmospheric concentrations of CO2 have continued to rise.

Estimated emissions reductions in 2020 relative to 2019 are of the order 4-7 per cent. This reduction might reduce the increase in atmospheric CO2 concentration by ~0.1-0.2 ppm compared to if there had there been no pandemic. However, this size change is well within the bounds of the current interannual variability (ranging from 2-3 ppm per year over the last decade), which is driven by variability in the natural carbon cycle.

Global efforts to curb greenhouse gas emissions in line with the Paris Agreement will need to harness structural changes to our energy and economic systems to lock in sustained emissions reductions of this order for several years before we see a significant slowing in the atmospheric growth rate of CO2 and begin to reap the benefits of avoided warming.

Last updated: 09 Sep 2020 6:37pm
Declared conflicts of interest:
None declared.
Dr Jonathan Symons is a senior lecturer in International Relations and a member of Climate Futures at Macquarie University in the Department of Modern History, Politics and International Relations

The 'United in Science' report estimates that in early April 2020, at the peak of the COVID-19 lockdowns, “daily global fossil CO2 emissions dropped 17 per cent”. However, as restrictions have eased, global emissions have now almost returned to pre-pandemic levels.

In 2020, global greenhouse gas emissions will be lower than in 2019. However, this is only thanks to the global COVID-19-induced recession. Atmospheric concentrations of greenhouse gases are continuing to increase at record rates. The gap between rhetoric and action on climate change is wider than ever.

If we are to limit warming to 1.5°C,  global emissions need to halve in each of the coming decades. Instead, in 2019, global emissions from fossil fuels increased slightly. A small decline in emissions from coal (–1.7 per cent) was offset by increased combustion of natural gas (2.0 per cent) and oil (0.8 per cent). 

Collectively, G20 countries are not on track to meet the commitments made under the Paris Agreement. However, the Paris targets are themselves hopelessly inadequate. Even if fully implemented, global emissions would actually be higher in 2030 than today.

The report stresses that limiting warming to 1.5°C will require “new technological solutions and gradual change in consumption patterns are needed at all levels." To reach net-zero emissions, measures that sequester or remove carbon dioxide from the atmosphere must also be developed.

The report identifies a 24 per cent chance that temperatures in one of the next five years will exceed 1.5°C above pre-industrial levels. 

The consequences of projected climate change for fire risk, sea-level rise and extreme weather events are already becoming apparent. The report estimates that the likelihood of weather conditions such as those that contributed to Australia’s recent wildfires have increased by at least 30 per cent since 1900."

My comment that responds to the report but does not summarise its content:

"Australia's political debate seems entirely disconnected from the scientific realities captured in the ‘United in Science’ report. It is not only that the Morrison Government lacks effective mitigation policies, it is failing to honour even some of its key promises. For example, it is not fulfilling its 2015 'Mission Innovation' pledge to double government spending on clean energy research and development by 2020. 

Meanwhile, the urgent need to develop negative emissions technologies, which the United in Science report identifies, has not yet entered mainstream debate. If current trends continue, we may soon also be debating more drastic and risky interventions. For example, calls to stabilise the global temperature through ‘solar geoengineering’ may grow louder. Trials to protect specific areas such as the Great Barrier Reef, via cloud brightening, are already underway.

Last updated: 09 Sep 2020 6:32pm
Declared conflicts of interest:
None declared.
Dr Jess Melbourne-Thomas is a Research Scientist at CSIRO Oceans and Atmosphere

This new United in Science 2020 Report is significant in that it brings together recent climate change updates from a group of key global science organisations. 

In particular, it provides compelling, science-based messages regarding current and near-future impacts of climate change. A key message is that there is a significant and growing chance of exceeding the 1.5°C global warming level in the next five years. 

Notably, the report summarises evidence that, while CO2 emissions have declined in 2020 in association with COVID19, these reductions will not lead to a discernible reduction in the atmospheric concentrations of long-lived greenhouses. Sustained reductions in emissions are needed to stabilise global warming.

The new report summarises findings from the IPCC-SROCC report, emphasising that ocean and ice environments around the world are changing at an unprecedented rate, with profound consequences for ecosystems and for human communities globally. 

The UiS Report describes so-called ‘High Impact Events’ influenced by anthropogenic climate change, including the 2019-2020 bushfires in Australia. The likelihood of the weather conditions that led to those wildfires has increased by at least 30 per cent since 1900, as a result of anthropogenic climate change.

Last updated: 09 Sep 2020 6:30pm
Declared conflicts of interest:
None declared.
Stephen Lincoln is Emeritus Professor in the School of Physical Sciences at the University of Adelaide and a Director of South Australian Nuclear Energy Systems

A new report entitled United in Science 2020, compiled by authors from a wide range of international agencies, provides a comprehensive and concise coverage of human-induced climate change. 

The findings are:

While the greenhouse gases, carbon dioxide and methane occur naturally in the atmosphere, a huge and growing global demand for energy has greatly increased their levels because of the production and use of fossil fuels.

Extensive agriculture has added to these carbon dioxide and methane levels. These two gases trap heat in the atmosphere. The result is that Earth’s average temperature has increased on average by 1.1°C above that prior to the beginning of the Industrial Revolution.

Ninety percent of this heat is transferred to the oceans, with the consequence that fish and other aquatic species are changing the regions of the oceans they occupy. This impacts on fisheries and food supply.
This warming also causes water to expand and sea levels to rise.

Additionally, this warming causes land-based glaciers to melt, such that more water flows into the oceans to add to sea-level rise. This in turn is likely to decrease the seasonal availability of fresh river water for 1.5 billion people.

Overall, sea level rise poses a severe threat of flooding to low-lying land, particularly to coral atolls.
In addition to these effects, it appears that the extremes of drought and heavy rainfall events will become more severe. In both cases this is likely to affect food supply adversely. In the case of drought, the likelihood of wildfires increases substantially.

To ensure that Earth’s human-induced temperature does not exceed a manageable 2°C, and preferably 1.5°C, as required by the Paris Agreement, a rapid and complete switch away from fossil fuel-based energy to alternative energy sources is required, in addition to a great increase in energy usage efficiency. 

In addition, methods for extracting carbon dioxide directly from the atmosphere will be necessary. Fortunately, these three objectives are now looking increasingly achievable, although it will be a close-run thing.

Last updated: 09 Sep 2020 6:29pm
Declared conflicts of interest:
None declared.
Dr Paul Read is Senior Research Fellow at the Monash Sustainability Institute at Monash University and a Co-Director of the National Centre for Research in Bushfire and Arson

Since 2010, multiple sources show record impacts on heatwaves, global temperatures, arctic melt and even arctic wildfires.

According to a report released today by the World Meteorological Organization (WMO) under direction of the United Nations Secretary-General, the impact of COVID-19 is similar to what is needed to bring the world back on track for the Paris Agreement, and the next five years to 2025 are critical.

Opportunities exist in renewables and behavioural change to divert catastrophe, but COVID shows just how much change is needed to avoid the worst impacts of climate change on our young - our children imminently face a decimated biosphere, mass extinction, more natural disasters, famine, heatwaves and water shortages. What confuses most climate scientists is how COVID, a disease where 80 percent of deaths affect the elderly (>65), rapidly shut down the global economy whereas carbon emissions have steadily increased 62 percent since climate negotiations began 30 years ago and we are now heading for an increase of 3.2 degrees Celsius by 2100.  

This means the collapse of the Amazon and the polar ice caps, ocean acidification, inundated coastal cities and most of the Mediterranean on fire, among others. Is the survival of our children less important than the elderly? The fact that the elderly (>55) took 70 percent of Australia's total $2.3 trillion earnings last year might have something to do with our national reticence to tackle climate change. Or is it that the top 1 percent in Australia own the same as the poorest 70 percent, mostly young?

Even though COVID confinement decreased emissions by 17 percent in April 2020, mostly from transport, the level it fell to was still way above 1990 levels, settling on the same global emissions of 2006. Within a month, July saw it rise back up close to 2019 levels. The end result is that COVID will hardly put the brakes on emissions precisely because more countries than ever are deeply embedded in the wrong kinds of economic development and the wrong kinds of consumption patterns.

According to this report, the world is undeniably failing to reach its 2030 Paris targets to keep global warming below +1.5 degrees Celsius, even despite COVID. The global trend has already reached +1.1 degrees Celsius since pre-industrial values.

Closer to home, all you need do is check the public BOM anomalies over the past 60 years to see Australian maxima increased by a whopping 1.5 degrees since 1950 alone, almost linearly, with the major crossover in 1985.

In line with this, the frequency of catastrophic Australian bushfires has gone from 85 years (in 1910) to every 8 years (2020), with at least 30 percent directly attributable to climate change.

School strikes and unprecedented megafires refocused our attention on climate change but the rise of COVID-19 swiftly diverted the world's attention. For anyone thinking COVID will dampen economic activity enough to forestall the worst of climate change, the latest report says no - whilst emissions have fallen to 2006 levels, the concentrations of carbon dioxide and methane in the atmosphere is still rising, even while the global economy is shut down.

This is because 93 percent of concentrations affecting temperature have come from past emissions with a lag time of about 10 years - those serving, once again, the major recipients of economic output, being the top 1 percent and the elderly.

On top of this, even with economic activity flattened by COVID, the world's economies in 2020 are still pumping out more emissions than they did during the Global Financial Crisis. This is because all nations are becoming, on average, more reliant on fossil fuels and meat consumption.

In essence, emissions have fallen due to economic dampening from COVID but concentrations continue to rise in the atmosphere. Australia has drastically reduced its carbon footprint per capita over the past decade, and even had 10 minutes on 6 November 2019 when 50% of the grid was powered by renewables, but it must increase efforts to model global citizenship so as to encourage the six largest emitters to do likewise - China, USA, EU28, India, Russia and Japan. Without action across all nations in the next five years, this report suggests we will hit runaway climate change before the end of the century, making much of the world uninhabitable.

Last updated: 09 Sep 2020 6:27pm
Declared conflicts of interest:
None declared.
Professor Nathan Bindoff is a physical oceanographer and program leader of Australia Antarctic Program Partnership. He was a Coordinating Lead Author of the IPCC AR4, AR5 and in AR6 on IPCC Special Report on Oceans and Cryosphere in a Changing Climate

The science is clear. Climate change is already affecting human communities. Sea-level rise is accelerating, flood risk is increasing for 1.6 billion more people, more than ever before. Extreme weather events on land and in the oceans have grown in number and frequency.  The research literature is clear and huge, some IPCC reports encompass assessments of more than 30,000 research papers and the scientific evidence is unequivocal.

Our ambition to mitigate climate change is falling further behind the Paris agreement and the agreed threshold of keeping warming to less than 2 degrees or better. Time is running out to meet these agreements. This report shows that climate change is an urgent problem and is essential reading.

Last updated: 09 Sep 2020 6:25pm
Declared conflicts of interest:
Potential Conflict: I was an coordinating lead author on the IPCC Special Report on Cryosphere and Changing Climate.

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