Landmark U.N. report says some climate effects permanent, still time to avoid others
"[This] report is a code red for humanity," U.N. Secretary-General Antonio Guterres said Monday of the IPCC climate report.
Climate activists gather outside the U.S. Capitol in Washington, D.C., on July 28. Photo by Sarah Silbiger/UPI | License Photo
Aug. 9 (UPI) -- A landmark report released on Monday cautions that global temperatures worldwide will probably surpass a level in about a decade that experts and officials have been trying to avert.
The nearly 4,000-page assessment was released by the United Nations Intergovernmental Panel of Climate Change. It's the panel's sixth climate report and the first since 2013.
According to the report, human influence on the climate is "unequivocal" affecting the atmosphere, ocean, cryosphere and biosphere -- but says there's still a chance to avoid the worst case scenario.
The report said the world is already seeing the effects of climate change, including longer heat waves, heavy precipitation, more frequent and sustained droughts and stronger tropical cyclones -- and that it's "widespread, rapid and intensifying."
"Global surface temperature will continue to increase until at least the mid-century under all emissions scenarios considered," the report states.
"Global warming of 1.5 degrees Celsius and 2 degrees Celsius will be exceeded during the 21st century unless deep reductions in carbon dioxide and other greenhouse gas emissions occur in the coming decades."
The report adds that the warmer climate will "intensify" very wet and very dry weather swings, climate events and seasons, but noted the "location and frequency of these events depends on projected changes in regional atmospheric circulation, including monsoons and mid-latitude storm tracks."
Limiting human impact, it said, would require cutting carbon emissions to "at least net zero" and making "strong reductions" in other greenhouse gas emissions.
"The scale of recent changes across the climate system as a whole and the present state of many aspects of the climate system are unprecedented over many centuries to many thousands of years," the panel said in a statement.
"Many changes due to past and future greenhouse gas emissions are irreversible for centuries to millennia, especially changes in the ocean, ice sheets and global sea level."
"This report is a reality check. We now have a much clearer picture of the past, present and future climate," said IPCC Working Group Co-Chair Valerie Masson-Delmotte said.
"Today's ... report is a code red for humanity," said U.N. Secretary-General Antonio Guterres. "Global heating is affecting every region on Earth, with many of the changes becoming irreversible."
"The evidence is irrefutable: Greenhouse gas emissions are choking our planet and placing billions of people in danger," he added in a tweet. "We must act decisively now to avert a climate catastrophe."
Landmark report maps out five scenarios for Earth's climate future
Paris Agreement climate targets could soon be out of reach without immediate and massive greenhouse gas emission reductions, says the Intergovernmental Panel on Climate Change (IPCC) in a landmark report published Monday.
“This report is a reality check,” said IPCC Working Group I co-chair Valérie Masson-Delmotte in a statement. “We now have a much clearer picture of the past, present and future climate, which is essential for understanding where we are headed, what can be done, and how we can prepare.”
The report offers a more granular analysis of how greenhouse gases (GHGs) contribute to global temperature increases, and spells out different emission scenarios to estimate how likely it is the planet will cross the Paris Agreement goal of holding global warming to “well below 2, preferably 1.5 degrees Celsius” compared to pre-industrial levels. The IPCC estimates that from 2011 to 2020, global surface temperature was 1.09 C higher than the 1850 to1900 pre-industrial average.
The five scenarios considered range from very high emissions (doubling of global GHGs by 2050) to very low emissions (net-zero by 2050 and negative emissions thereafter), with its intermediate scenario representing emissions holding at current levels until mid-century.
“Global surface temperature will continue to increase until at least the mid-century under all emissions scenarios considered,” the report reads. “Global warming of 1.5 C and 2 C will be exceeded during the 21st century unless deep reductions in CO2 and other greenhouse gas emissions occur in the coming decades.”
The IPCC’s best estimate in its lowest-emission scenario sees warming held to 1.4 C by the end of the century, with its best estimate in the highest-emission scenario coming in at 4.4 C warming.
As the planet warms, the IPCC warns heat waves, droughts, cyclones, and heavy rain will all become more common, posing a direct threat to agriculture and human safety. Then there is Arctic sea ice, snow cover, and permafrost that is melting and contributing to sea level rise and methane leaking into the atmosphere, potentially representing a tipping point for the Earth’s climate.
Tipping points in climate science refer to a threshold that, when crossed, lock in major damage. Scientists are still developing better understandings of how tipping points work, but they essentially represent a minefield on the road to net-zero given the uncertainty. Carbon sinks turning into carbon emitters, like Canada’s managed forest, or Greenland rapidly losing more than 18 billion tonnes of ice contributing to sea level rise are just potential two examples.
The IPCC report highlights the Atlantic Meridional Overturning Circulation (AMOC), the system of ocean currents that includes the Gulf Stream, as one important tipping point. The IPCC says the AMOC is “very likely” to weaken over the 21st century under all scenarios, but only has “medium confidence” there won’t be an “abrupt collapse” before 2100. If it collapsed, the world’s weather patterns would be dramatically impacted.
In fact, one study published last week in Nature Climate Change found evidence the AMOC was weakening, and warned a collapse would have “severe impacts” and increase the risk of cascading problems for other major Earth systems, “such as the Antarctic ice sheet, tropical monsoon systems and Amazon rainforest.”
“Hopefully, as our governments head to COP26, they will have all of this in mind, and they will make those new commitments as ambitious as science requires them to be,” says Pembina Institute director of federal policy Isabelle Turcotte.
“We need to do more at the federal level, (but) we also need to come back home domestically and make sure all provinces are energetically rowing in the same direction,” she said.
Canada has pledged to reduce emissions between 40 and 45 per cent below 2005 levels by 2030, but its latest modelling forecasts a 36 per cent reduction by 2030. Moreover, the IPCC previously said to hold global warming to 1.5 C there should be about a 45 per cent reduction in global GHGs from 2010 levels. Because global GHG emissions were higher in 2010 than in 2005, Canada’s commitment to lower emissions 40 to 45 per cent below 2005 levels is actually a weaker pledge than what the IPCC called for.
“We are not yet aligned with what science says the global target should be, so Canada needs to do more,” said Turcotte. “But we also need to keep in mind that Canada is a rich country that has hugely benefited from extracting and burning fossil fuels, and so we have a carbon debt to the world, and we need to do more than the global average effort.”
A recent report from the Pembina Institute found 95 per cent of Canadian emissions are not covered by a provincial or territorial 2030 climate target. It also found no jurisdiction had developed a path to net-zero. Because provinces hold jurisdiction over natural resource development, it is a major gap in the country’s climate ambition.
“Absent these provinces stepping up, Canada is unlikely to meet any climate target,” Turcotte said.
Turcotte pointed to the importance of carbon budgets as a tool for decarbonizing. One reason they are helpful is that a carbon budget lays out the amount of emissions a jurisdiction can generate. That shifts the focus somewhat away from the less important goal of net-zero by 2050 toward the more important question of how much carbon is emitted in the intervening years. She said net-zero is an “important longer-term milestone,” but the focus on it can be misleading.
“It could lead us to climate catastrophe, because net-zero is an emissions level in 2050,” she said. “What matters is the cumulative amount of CO2 we emit from now until 2050, or from now until we get to net-zero.”
John Woodside, Local Journalism Initiative Reporter, Canada's National Observer
‘Nowhere to run’: UN report says global warming nears limits
Earth is getting so hot that temperatures in about a decade will probably blow past a level of warming that world leaders have sought to prevent, according to a report released Monday that the United Nations called a “code red for humanity.”
“It’s just guaranteed that it’s going to get worse,” said report co-author Linda Mearns, a senior climate scientist at the U.S. National Center for Atmospheric Research. “Nowhere to run, nowhere to hide.”
But scientists also eased back a bit on the likelihood of the absolute worst climate catastrophes.
The authoritative Intergovernmental Panel on Climate Change (IPCC) report, which calls climate change clearly human-caused and “unequivocal,” makes more precise and warmer forecasts for the 21st century than it did last time it was issued in 2013.
Each of five scenarios for the future, based on how much carbon emissions are cut, passes the more stringent of two thresholds set in the 2015 Paris climate agreement. World leaders agreed then to try to limit warming to 1.5 degrees Celsius (2.7 degrees Fahrenheit) above levels in the late 19th century because problems mount quickly after that. The world has already warmed nearly 1.1 degrees Celsius (2 degrees Fahrenheit) since then.
Under each scenario, the report said, the world will cross the 1.5-degree-Celsius warming mark in the 2030s, earlier than some past predictions. Warming has ramped up in recent years, data shows.
“Our report shows that we need to be prepared for going into that level of warming in the coming decades. But we can avoid further levels of warming by acting on greenhouse gas emissions,” said report co-chair Valerie Masson-Delmotte, a climate scientist at France’s Laboratory of Climate and Environment Sciences at the University of Paris-Saclay.
In three scenarios, the world will also likely exceed 2 degrees Celsius (3.6 degrees Fahrenheit) over pre-industrial times — the less stringent Paris goal — with far worse heat waves, droughts and flood-inducing downpours unless there are deep emissions cuts, the report said.
FILE - In this Wednesday, Feb. 17, 2021 file photo, a floating dock sits on the lakebed of the Suesca lagoon, in Suesca, Colombia. The lagoon, a popular tourist destination near Bogota that has no tributaries and depends on rain runoff, has radically decreased its water surface due to years of severe droughts in the area and the deforestation and erosion of its surroundings. (AP Photo/Fernando Vergara, File)
“This report tells us that recent changes in the climate are widespread, rapid and intensifying, unprecedented in thousands of years,” said IPCC Vice Chair Ko Barrett, senior climate adviser for the U.S. National Oceanic and Atmospheric Administration.
With crucial international climate negotiations coming up in Scotland in November, world leaders said the report is causing them to try harder to cut carbon pollution. U.S. Secretary of State Anthony Blinken called it “a stark reminder.”
The 3,000-plus-page report from 234 scientists said warming is already accelerating sea level rise and worsening extremes such as heat waves, droughts, floods and storms. Tropical cyclones are getting stronger and wetter, while Arctic sea ice is dwindling in the summer and permafrost is thawing. All of these trends will get worse, the report said.
For example, the kind of heat wave that used to happen only once every 50 years now happens once a decade, and if the world warms another degree Celsius (1.8 degrees Fahrenheit), it will happen twice every seven years, the report said.
As the planet warms, places will get hit more not just by extreme weather but by multiple climate disasters at once, the report said. That’s like what’s now happening in the Western U.S., where heat waves, drought and wildfires compound the damage, Mearns said. Extreme heat is also driving massive fires in Greece and Turkey.
Some harm from climate change — dwindling ice sheets, rising sea levels and changes in the oceans as they lose oxygen and become more acidic — is “irreversible for centuries to millennia,” the report said.
The world is “locked in” to 15 to 30 centimeters (6 to 12 inches) of sea level rise by mid-century, said report co-author Bob Kopp of Rutgers University.
Scientists have issued this message for more than three decades, but the world hasn’t listened, said United Nations Environment Program Executive Director Inger Andersen.
For the first time, the report offers an interactive atlas for people to see what has happened and may happen to where they live.
Nearly all of the warming that has happened on Earth can be blamed on emissions of heat-trapping gases such as carbon dioxide and methane. At most, natural forces or simple randomness can explain one- or two-tenths of a degree of warming, the report said.
FILE - In this Tuesday, July 20, 2021 file photok the Staten Island Ferry departs from the Manhattan terminal through a haze of smoke with the Statue of Liberty barely visible in New York. Wildfires in the American West, including one burning in Oregon that's currently the largest in the U.S., are creating hazy skies as far away as New York as the massive infernos spew smoke and ash into the air in columns up to six miles high. (AP Photo/Julie Jacobson)
The report described five different future scenarios based on how much the world reduces carbon emissions. They are: a future with incredibly large and quick pollution cuts; another with intense pollution cuts but not quite as massive; a scenario with moderate emission cuts; a fourth scenario where current plans to make small pollution reductions continue; and a fifth possible future involving continued increases in carbon pollution.
In five previous reports, the world was on that final hottest path, often nicknamed “business as usual.” But this time, the world is somewhere between the moderate path and the small pollution reductions scenario because of progress to curb climate change, said report co-author Claudia Tebaldi, a scientist at the U.S. Pacific Northwest National Lab.
While calling the report “a code red for humanity,” U.N. Secretary-General Antonio Guterres kept a sliver of hope that world leaders could still somehow prevent 1.5 degrees of warming, which he said is “perilously close.”
Alok Sharma, the president of the upcoming climate negotiations in Scotland, urged leaders to do more so they can “credibly say that we have kept 1.5 degrees alive.”
“Anything we can do to limit, to slow down, is going to pay off,” Tebaldi said. “And if we cannot get to 1.5, it’s probably going to be painful, but it’s better not to give up.”
In the report’s worst-case scenario, the world could be around 3.3 degrees Celsius (5.9 degrees Fahrenheit) hotter than now by the end of the century. But that scenario looks increasingly unlikely, said report co-author and climate scientist Zeke Hausfather, climate change director of the Breakthrough Institute.
“We are a lot less likely to get lucky and end up with less warming than we thought,” Hausfather said. “At the same time, the odds of ending up in a much worse place than we expected if we do reduce our emissions are notably lower.”
The report said ultra-catastrophic disasters — commonly called “tipping points,” like ice sheet collapses and the abrupt slowdown of ocean currents — are “low likelihood” but cannot be ruled out. The much talked-about shutdown of Atlantic ocean currents, which would trigger massive weather shifts, is something that’s unlikely to happen in this century, Kopp said.
A “major advance” in the understanding of how fast the world warms with each ton of carbon dioxide emitted allowed scientists to be far more precise in the scenarios in this report, Mason-Delmotte said.
In a new move, scientists emphasized how cutting airborne levels of methane — a powerful but short-lived gas that has soared to record levels — could help curb short-term warming. Lots of methane the atmosphere comes from leaks of natural gas, a major power source. Livestock also produces large amounts of the gas, a good chunk of it in cattle burps.
More than 100 countries have made informal pledges to achieve “net zero” human-caused carbon dioxide emissions sometime around mid-century, which will be a key part of the negotiations in Scotland. The report said those commitments are essential.
“It is still possible to forestall many of the most dire impacts,” Barrett said.
___
Read more of AP’s climate coverage at http://www.apnews.com/Climate
___
Follow Seth Borenstein on Twitter at @borenbears.
___
The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute’s Department of Science Education. The AP is solely responsible for all content.
In this Monday, July 26, 2021 file photo, a man carries goods on his bicycle as he walks out of the the Yubei Agricultural and Aquatic Products World in Xinxiang in central China's Henan Province. The Intergovernmental Panel on Climate Change report released on Monday, Aug. 9, 2021, says warming already is smacking Earth hard and quickly with accelerating sea level rise, shrinking ice and worsening extremes such as heat waves, droughts, floods and storms. (AP Photo/Dake Kang, File)
Earth is getting so hot that temperatures in about a decade will probably blow past a level of warming that world leaders have sought to prevent, according to a report released Monday that the United Nations called a “code red for humanity.”
“It’s just guaranteed that it’s going to get worse,” said report co-author Linda Mearns, a senior climate scientist at the U.S. National Center for Atmospheric Research. “Nowhere to run, nowhere to hide.”
But scientists also eased back a bit on the likelihood of the absolute worst climate catastrophes.
The authoritative Intergovernmental Panel on Climate Change (IPCC) report, which calls climate change clearly human-caused and “unequivocal,” makes more precise and warmer forecasts for the 21st century than it did last time it was issued in 2013.
Each of five scenarios for the future, based on how much carbon emissions are cut, passes the more stringent of two thresholds set in the 2015 Paris climate agreement. World leaders agreed then to try to limit warming to 1.5 degrees Celsius (2.7 degrees Fahrenheit) above levels in the late 19th century because problems mount quickly after that. The world has already warmed nearly 1.1 degrees Celsius (2 degrees Fahrenheit) since then.
Under each scenario, the report said, the world will cross the 1.5-degree-Celsius warming mark in the 2030s, earlier than some past predictions. Warming has ramped up in recent years, data shows.
“Our report shows that we need to be prepared for going into that level of warming in the coming decades. But we can avoid further levels of warming by acting on greenhouse gas emissions,” said report co-chair Valerie Masson-Delmotte, a climate scientist at France’s Laboratory of Climate and Environment Sciences at the University of Paris-Saclay.
In three scenarios, the world will also likely exceed 2 degrees Celsius (3.6 degrees Fahrenheit) over pre-industrial times — the less stringent Paris goal — with far worse heat waves, droughts and flood-inducing downpours unless there are deep emissions cuts, the report said.
FILE - In this Friday, Aug. 6, 2021 file photo, smoke spreads over Parnitha mountain during a wildfire in the village of Ippokratios Politia, Greece, about 35 kilometres (21 miles), north of Athens. Thousands of people fled wildfires burning out of control in Greece and Turkey on Friday, as a protracted heat wave left forests tinder-dry and flames threatened populated areas and electricity installations. (AP Photo/Lefteris Pitarakis)
FILE - This Thursday, July 15, 2021 file photo shows destroyed houses in Schuld, Germany. Due to heavy rains, the Ahr River dramatically flooded over its banks the previous evening. (AP Photo/Michael Probst)
FILE - In this Wednesday, Feb. 17, 2021 file photo, a floating dock sits on the lakebed of the Suesca lagoon, in Suesca, Colombia. The lagoon, a popular tourist destination near Bogota that has no tributaries and depends on rain runoff, has radically decreased its water surface due to years of severe droughts in the area and the deforestation and erosion of its surroundings. (AP Photo/Fernando Vergara, File)
“This report tells us that recent changes in the climate are widespread, rapid and intensifying, unprecedented in thousands of years,” said IPCC Vice Chair Ko Barrett, senior climate adviser for the U.S. National Oceanic and Atmospheric Administration.
With crucial international climate negotiations coming up in Scotland in November, world leaders said the report is causing them to try harder to cut carbon pollution. U.S. Secretary of State Anthony Blinken called it “a stark reminder.”
The 3,000-plus-page report from 234 scientists said warming is already accelerating sea level rise and worsening extremes such as heat waves, droughts, floods and storms. Tropical cyclones are getting stronger and wetter, while Arctic sea ice is dwindling in the summer and permafrost is thawing. All of these trends will get worse, the report said.
For example, the kind of heat wave that used to happen only once every 50 years now happens once a decade, and if the world warms another degree Celsius (1.8 degrees Fahrenheit), it will happen twice every seven years, the report said.
As the planet warms, places will get hit more not just by extreme weather but by multiple climate disasters at once, the report said. That’s like what’s now happening in the Western U.S., where heat waves, drought and wildfires compound the damage, Mearns said. Extreme heat is also driving massive fires in Greece and Turkey.
Some harm from climate change — dwindling ice sheets, rising sea levels and changes in the oceans as they lose oxygen and become more acidic — is “irreversible for centuries to millennia,” the report said.
The world is “locked in” to 15 to 30 centimeters (6 to 12 inches) of sea level rise by mid-century, said report co-author Bob Kopp of Rutgers University.
Scientists have issued this message for more than three decades, but the world hasn’t listened, said United Nations Environment Program Executive Director Inger Andersen.
For the first time, the report offers an interactive atlas for people to see what has happened and may happen to where they live.
Nearly all of the warming that has happened on Earth can be blamed on emissions of heat-trapping gases such as carbon dioxide and methane. At most, natural forces or simple randomness can explain one- or two-tenths of a degree of warming, the report said.
FILE - In this Thursday, July 29, 2021 file photo, birds fly over a man taking photos of the exposed riverbed of the Old Parana River, a tributary of the Parana River during a drought in Rosario, Argentina. Parana River Basin and its related aquifers provide potable water to close to 40 million people in South America, and according to environmentalists the falling water levels of the river are due to climate change, diminishing rainfall, deforestation and the advance of agriculture. (AP Photo/Victor Caivano, File)
FILE - In this Tuesday, July 20, 2021 file photok the Staten Island Ferry departs from the Manhattan terminal through a haze of smoke with the Statue of Liberty barely visible in New York. Wildfires in the American West, including one burning in Oregon that's currently the largest in the U.S., are creating hazy skies as far away as New York as the massive infernos spew smoke and ash into the air in columns up to six miles high. (AP Photo/Julie Jacobson)
The report described five different future scenarios based on how much the world reduces carbon emissions. They are: a future with incredibly large and quick pollution cuts; another with intense pollution cuts but not quite as massive; a scenario with moderate emission cuts; a fourth scenario where current plans to make small pollution reductions continue; and a fifth possible future involving continued increases in carbon pollution.
In five previous reports, the world was on that final hottest path, often nicknamed “business as usual.” But this time, the world is somewhere between the moderate path and the small pollution reductions scenario because of progress to curb climate change, said report co-author Claudia Tebaldi, a scientist at the U.S. Pacific Northwest National Lab.
While calling the report “a code red for humanity,” U.N. Secretary-General Antonio Guterres kept a sliver of hope that world leaders could still somehow prevent 1.5 degrees of warming, which he said is “perilously close.”
Alok Sharma, the president of the upcoming climate negotiations in Scotland, urged leaders to do more so they can “credibly say that we have kept 1.5 degrees alive.”
“Anything we can do to limit, to slow down, is going to pay off,” Tebaldi said. “And if we cannot get to 1.5, it’s probably going to be painful, but it’s better not to give up.”
In the report’s worst-case scenario, the world could be around 3.3 degrees Celsius (5.9 degrees Fahrenheit) hotter than now by the end of the century. But that scenario looks increasingly unlikely, said report co-author and climate scientist Zeke Hausfather, climate change director of the Breakthrough Institute.
“We are a lot less likely to get lucky and end up with less warming than we thought,” Hausfather said. “At the same time, the odds of ending up in a much worse place than we expected if we do reduce our emissions are notably lower.”
The report said ultra-catastrophic disasters — commonly called “tipping points,” like ice sheet collapses and the abrupt slowdown of ocean currents — are “low likelihood” but cannot be ruled out. The much talked-about shutdown of Atlantic ocean currents, which would trigger massive weather shifts, is something that’s unlikely to happen in this century, Kopp said.
A “major advance” in the understanding of how fast the world warms with each ton of carbon dioxide emitted allowed scientists to be far more precise in the scenarios in this report, Mason-Delmotte said.
In a new move, scientists emphasized how cutting airborne levels of methane — a powerful but short-lived gas that has soared to record levels — could help curb short-term warming. Lots of methane the atmosphere comes from leaks of natural gas, a major power source. Livestock also produces large amounts of the gas, a good chunk of it in cattle burps.
More than 100 countries have made informal pledges to achieve “net zero” human-caused carbon dioxide emissions sometime around mid-century, which will be a key part of the negotiations in Scotland. The report said those commitments are essential.
“It is still possible to forestall many of the most dire impacts,” Barrett said.
___
Read more of AP’s climate coverage at http://www.apnews.com/Climate
___
Follow Seth Borenstein on Twitter at @borenbears.
___
The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute’s Department of Science Education. The AP is solely responsible for all content.
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