Scientists Discover Mechanism that Can Cause Collapse of Great Atlantic Circulation System October 18, 2022
Introduction:
(EurekAlert) The Atlantic meridional overturning circulation (AMOC), a system of ocean currents that carry warm water from the tropics into the North Atlantic and transport cold water from the northern to the southern hemisphere, is a fundamental mechanism for the regulation of Earth’s climate. The conveyor belt has collapsed in the past owing to natural factors. The most recent collapse played a key role in the last deglaciation. AMOC is now threatened by global warming, scientists have shown, and a new study has discovered the sequence of past breakdown events.
The study was conducted by German researchers and Brazilian paleoclimatologist Cristiano Mazur Chiessi, a professor at the University of São Paulo’s School of Arts, Sciences and Humanities (EACH-USP) in Brazil. An article reporting their findings is published in Nature Communications.
“An investigation of marine sediments collected between Canada and Greenland led to the discovery that, in the past, glaciers covering the territories that now correspond to Canada and the northern United States released colossal numbers of icebergs into the Atlantic owing to ocean surface warming in the region,” Chiessi told Agência FAPESP.
The icebergs melted in the ocean and deposited continental sediments on the seabed. “Identification of these sediments and reconstitution of the subsurface temperature in the region enabled scientists to establish for the first time that subsurface warming preceded the mass iceberg release,” he said.
The enormous volume of fresh water added by the melting of the icebergs modified the composition of the ocean at high latitudes of the northern hemisphere. This had a tremendous impact on the global climate because the region between Canada and Greenland is a particularly sensitive part of AMOC.
Upper ocean heating in the equatorial Pacific—a key oceanographic region in Earth's climate system—is likely to make the East Asian monsoon season wetter, according to a study co-authored by a Rutgers researcher.
Recent increases in ocean heat content—where energy is absorbed by the waters—have been implicated in the intensification of tropical storms that draw their energy from the surface of the ocean. The link between ocean heating and rainfall on land is, however, less clear. A study published in Nature provides insight into this link.
"Our study suggests variations in ocean thermal structure affect the delivery of moisture, latent heat, and what happens when they arrive on land," said Yair Rosenthal, a professor of marine and coastal sciences in the Rutgers' School of Art and Sciences and School of Environmental and Biological Sciences.
Rosenthal said the changes in the latitudinal temperature gradient—the difference in sea-surface temperature between low and high latitudes—not only control how energy is absorbed by the equatorial upper ocean but how winds carry the moisture from the ocean onto land.
The study, led by Zhimin Jian of Tongji University in China, found that over the past 360,000 years, increases in monsoonal rain in eastern China correlated with increases in the heat content of the Indo-Pacific Warm Pool–a region where sea surface temperatures remain above ~82°F year-round–likely due to enhanced transport of moisture and latent heat absorbed in the water vapor from the ocean to the continent.
Addressing Climate Change With Satellites: Canada Will Contribute to NASA's International Atmosphere Observing System
October 18, 2022
Introduction:
(Canadian Space Agency) The Honourable François-Philippe Champagne, Minister of Innovation, Science and Industry, announced today that Canada will contribute to the Atmosphere Observing System (AOS) mission led by NASA. Canada's contribution is estimated at more than $200 million. Currently slated to launch in 2028 and 2031, this major multi-satellite mission will improve extreme weather prediction, climate modelling, and monitoring of disasters.
Extreme weather events are increasing in frequency and intensity. The dynamics of our planet's atmosphere are changing. We need better environmental prediction to support adaptation and climate resilience. The AOS, including its Canadian contribution, will measure aerosols and clouds, and how they interact to impact Earth's weather and climate.
Canada's contribution to the AOS is the High-altitude Aerosols, Water vapour and Clouds (HAWC) mission. It consists of two Canadian instruments on a Canadian satellite and a third instrument on a NASA satellite, all planned for launch in 2031. These innovative instruments will provide critical data, enabling Canadian climate scientists and weather forecasters to better understand and predict extreme events, like severe storms, floods, droughts and poor air quality conditions. HAWC and AOS data will be fully accessible.
Thanks to early investments from the Canadian Space Agency in concept studies and technology development for these instruments, Canada was well positioned to take part in this important climate science mission. Canadian collaborators in the HAWC mission include a coast-to-coast consortium of universities, Environment and Climate Change Canada, Natural Resources Canada and the National Research Council of Canada.
Canada's contribution to the AOS mission supports the implementation of Resourceful, Resilient, Ready: Canada's Strategy for Satellite Earth Observation, which describes how Canada will take full advantage of the unique vantage point of space to address climate change and other key challenges of our time.
Methane-eating ‘Borgs’ Have Been Assimilating Earth’s Microbes October 19, 2022
Introduction:
(EurekAlert) In Star Trek, the Borg are a ruthless, hive-minded collective that assimilate other beings with the intent of taking over the galaxy. Here on nonfictional planet Earth, Borgs are DNA packages that could help humans fight climate change.
Last year, a team led by Jill Banfield discovered DNA structures within a methane-consuming microbe called Methanoperedens that appear to supercharge the organism’s metabolic rate. They named the genetic elements “Borgs” because the DNA within them contains genes assimilated from many organisms. In a study published today in Nature, the researchers describe the curious collection of genes within Borgs and begin to investigate the role these DNA packages play in environmental processes, such as carbon cycling.
First contact
Methanoperedens are a type of archaea (unicellular organisms that resemble bacteria but represent a distinct branch of life) that break down methane (CH4) in soils, groundwater, and the atmosphere to support cellular metabolism. Methanoperedens and other methane-consuming microbes live in diverse ecosystems around the world but are believed to be less common than microbes that use photosynthesis, oxygen, or fermentation for energy. Yet they play an outsized role in Earth system processes by removing methane – the most potent greenhouse gas – from the atmosphere. Methane traps 30 times more heat than carbon dioxide and is estimated to account for about 30 percent of human-driven global warming. The gas is emitted naturally through geological processes and by methane-generating archaea; however, industrial processes are releasing stored methane back into the atmosphere in worrying quantities.
Banfield, a faculty scientist at Lawrence Berkeley National Laboratory (Berkeley Lab) and professor of Earth & Planetary Science and Environmental Science, Policy & Management at UC Berkeley, studies how microbial activities shape large-scale environmental processes and how, in turn, environmental fluctuations alter the planet’s microbiomes. As part of this work, she and her colleagues regularly sample microbes in different habitats to see what interesting genes microbes are using for survival, and how these genes might affect global cycles of key elements, such as carbon, nitrogen, and sulfur.
The Lightness of Water Vapor Adds Heft to Global Climate Models October 24, 2022
Introduction:
(EurekAlert) Clouds are notoriously hard to pin down, especially in climate science.
A study from the University of California, Davis, and published in the journal Nature Geoscience shows that air temperature and cloud cover are strongly influenced by the buoyancy effect of water vapor, an effect currently neglected in some leading global climate models.
Global climate models are the primary tools used to study Earth’s climate, predict its future changes and inform climate policymaking. However, climate models often differ on the precise degree of future warming, largely due to their representation of clouds.
“Climate models are the best tool we have to predict future climate change,” said lead author Da Yang, an assistant professor of atmospheric science at UC Davis and faculty scientist at Lawrence Berkeley National Lab. “It’s important that we actively try to improve them.”
Cold air rises?
While conventional wisdom has it that hot air rises, the reverse is true in the tropical atmosphere, the study notes. Previous research by Yang and his colleagues proposed that cold air rises in the tropics because humid air is lighter than dry air. This effect is known as vapor buoyancy, and it regulates the amount of low clouds over the subtropical ocean.
Exposing the Financial Costs of Climate Change—and Denial of the Climate Crisis by Mark Shapiro
October 24, 2022
Introduction:
(Mother Jones) Biting the Hand
It hasn’t been the best season for the invisible hand, the 18th century principle that the market be left to its own devices free of government intervention. In August, President Biden took his right hand and applied his signature to the Inflation Reduction Act (IRA) — signaling that the government would be tipping scales in the economy toward renewable energy. While unanimous opposition from Republicans signaled their continuing lip service to that free market ideology, in truth they — along with some Democrats — have long manipulated the economics of energy by steering billions of dollars in public funds toward the fossil fuel industry.
Fossil fuel companies have received at least $20 billion annually in federal and state government subsidies over the past 10 years alone, and as much as $6 trillion from governments worldwide. U.N. Secretary-General António Guterres declared in September that the industry was “feasting off subsidies” while our planet burns. So there’s an important frame to the story of the IRA that’s worth remembering: The $141 billion it allocates to support wind and solar industries represents what is likely the first time that subsidies and tax credits for renewable energy in the United States have exceeded subsidies to fossil fuel companies — and is just about two-thirds of what the petrochemical companies have received from the government over the past decade.
The massive government support for oil and gas interests was largely missing from the reporting on the IRA, and is certainly worthy of greater media scrutiny moving forward. In the U.S. those subsidies come in the form of loan guarantees, tax breaks and discounted rates for drilling on public lands, and in some cases direct payments to explore for oil in difficult locales — all provided to the companies that are, collectively, most responsible for the massive and expensive climate disruptions being experienced on Earth. Identifying which fossil fuel companies receive those different forms of direct and indirect government aid would be a significant contribution to the public interest — particularly since the public funds the subsidies, and the public pays for the billions of dollars in damages to the economy from the companies’ greenhouse gas emissions.
Climate warming methane emissions rising faster than ever, study says
By Steven Mufson
Updated October 26, 2022 at 11:09 a.m. EDT | Published October 26, 2022 at 10:24 a.m. EDT
The amount of methane in the atmosphere is racing ahead at an accelerating pace, according to a study by the World Meteorological Organization, threatening to undermine efforts to slow climate change.
The WMO’s Greenhouse Gas Bulletin said that “global emissions have rebounded since the COVID-related lockdowns” and that the increases in methane levels in 2020 and 2021 were the largest since systematic record keeping began in 1983.
10 steps you can take to lower your carbon footprint
“Methane concentrations are not just rising, they’re rising faster than ever,” said Rob Jackson, a professor of Earth system science at Stanford University.
The study comes on the same day as a new U.N. report which says that the world’s governments haven’t committed to cut enough climate emissions, putting the world on track for a 2.5 degree Celsius (4.5 degree Fahrenheit) increase in global temperatures by the end of the century.
Greenhouse gases reach a new record as nations fall behind on climate pledges
Source: NPR
Earlier on Wednesday the U.N's climate office said current pledges to cut greenhouse gas emissions put the planet on course to blow past the limit for global warming countries agreed to in the 2015 Paris climate accord.
It said its latest estimate based on 193 national emissions targets would see temperatures rise to 2.5 degrees Celsius (4.5 Fahrenheit) above pre-industrial averages by the end of the century, a full degree higher than the ambitious goal set in the Paris pact to limit warming by 1.5 C (2.7 F).
"We are still nowhere near the scale and pace of emission reductions required to put us on track toward a 1.5 degrees Celsius world," the head of the U.N. climate office, Simon Stiell, said in a statement. "To keep this goal alive, national governments need to strengthen their climate action plans now and implement them in the next eight years."
Scientists Warn in Report that Climate Change Has Pushed Earth to “Code Red” October 26, 2022
Introduction:
(EurekAlert) Writing in the journal BioScience, an international coalition led by Oregon State University researchers says in a report published today that the Earth’s vital signs have reached “code red” and that “humanity is unequivocally facing a climate emergency.”
In the special report, “World Scientists’ Warning of a Climate Emergency 2022,” the authors note that 16 of 35 planetary vital signs they use to track climate change are at record extremes. The report’s authors share new data illustrating increasing frequency of extreme heat events, rising global tree cover loss because of fires, and a greater prevalence of the mosquito-borne dengue virus. Further, they note that atmospheric carbon dioxide levels have reached 418 parts per million, the highest on record.
William Ripple, a distinguished professor in the OSU College of Forestry, and postdoctoral researcher Christopher Wolf are the lead authors of the report, and 10 other U.S. and global scientists are co-authors.
“Look at all of these heat waves, fires, floods and massive storms,” Ripple said. “The specter of climate change is at the door and pounding hard.”
The report follows by five years the “World Scientists’ Warning to Humanity: A Second Notice” published by Ripple and colleagues in BioScience and co-signed by more than 15,000 scientists in 184 countries.
Climate change could alter wind regimes so much by the end of this century that desert dunes and sand seas may impact human infrastructure, agriculture and homes, finds new study by King's researchers.
In a new study published in Nature Climate Change, King's researchers have analyzed future wind regimes to predict the impact of morphing sand dunes. The encroachment of these moving desert dunes has the potential to threaten transportation infrastructure, industry, agriculture and settlements—with the possibility of entire villages disappearing under sand.
Desert dunes and sand seas cover approximately 20% of the world's arid zones. Analyzing data on the shape, migration speed and direction of mobile desert dunes around the world, Dr. Andreas Baas and Lucie Delobel from the Department of Geography have used future wind patterns altered by climate change to determine the impact on these changing landscapes.
Previous studies on climate change have focused on heat and water to determine the impacts on local environments. However, focusing on wind has allowed the researchers to predict the future consequences of climate change on arid regions such as the Sahara, The Horn of Africa, the Southern Arabian Peninsula, South Asia, China and Australia.
"Most climate change studies focus on water, including sea-level rise, glaciers and ice sheets, and much less has been done on changing wind regimes. In many arid countries the impact of changing winds on desert dunes may be more important than things like sea-level rise," says Baas.
Heat Waves Driven by Climate Change Have Cost Global Economy Trillions Since 1990s October 28, 2022
Introduction:
(EurekAlert) Massive economic losses due to sweltering temperatures brought on by human-caused climate change are not just a problem for the distant future. A study in the journal Science Advances has found that more severe heat waves resulting from global warming have already cost the world economy trillions of dollars since the early 1990s — with the world’s poorest and lowest carbon-emitting nations suffering the most.
Dartmouth College researchers combined newly available, in-depth economic data for regions worldwide with the average temperature for the hottest five-day period — a commonly used measurement of heat intensity — for each region in each year. They found that from 1992-2013, heat waves statistically coincided with variations in economic growth and that an estimated $16 trillion was lost to the effects of high temperatures on human health, productivity and agricultural output.
The findings stress the immediate need for policies and technologies that protect people during the hottest days of the year, particularly in the world’s warmest, most economically vulnerable nations, the researchers report.
“Accelerating adaptation measures within the hottest period of each year would deliver economic benefits now,” said first author Christopher Callahan, a doctoral candidate in geography at Dartmouth. “The amount of money spent on adaptation measures should not be assessed just on the price tag of those measures, but relative to the cost of doing nothing. Our research identifies a substantial price tag to not doing anything.”
The study is the among the first to specifically examine how heat waves affect economic output, said senior author Justin Mankin, an assistant professor of geography at Dartmouth. “No one has shown an independent fingerprint for extreme heat and the intensity of that heat’s impact on economic growth. The true costs of climate change are far higher than we’ve calculated so far,” Mankin said.
Massive economic losses due to sweltering temperatures brought on by human-caused climate change are not just a problem for the distant future. A study in the journal Science Advances has found that more severe heat waves resulting from global warming have already cost the world economy trillions of dollars since the early 1990s—with the world's poorest and lowest carbon-emitting nations suffering the most.
Dartmouth College researchers combined newly available, in-depth economic data for regions worldwide with the average temperature for the hottest five-day period—a commonly used measurement of heat intensity—for each region in each year. They found that from 1992–2013, heat waves statistically coincided with variations in economic growth and that an estimated $16 trillion was lost to the effects of high temperatures on human health, productivity and agricultural output.
The findings stress the immediate need for policies and technologies that protect people during the hottest days of the year, particularly in the world's warmest, most economically vulnerable nations, the researchers report.
"Accelerating adaptation measures within the hottest period of each year would deliver economic benefits now," said first author Christopher Callahan, a doctoral candidate in geography at Dartmouth. "The amount of money spent on adaptation measures should not be assessed just on the price tag of those measures, but relative to the cost of doing nothing. Our research identifies a substantial price tag to not doing anything."
Climate Change Could Trigger the Congo Peatlands to Release Billions of Tons of Carbon November 2, 2022
Introduction:
(EurekAlert) Climate change could trigger the Congo peatlands to release billions of tonnes of carbon
• New research finds the peatlands are fragile and vulnerable to drought
• As the peatlands dry, the peat decomposes and releases carbon dioxide which accelerates global warming
• Study says this process has already happened once in the peatlands history - and could happen again
New research published in Nature today (Wed, Nov 2) reveals that the world’s largest tropical peatland turned from being a major store of carbon to a source of damaging carbon dioxide emissions as a result of climate change thousands of years ago.
Around the time that Stonehenge was built, 5,000 years ago, the climate of central Congo began to dry leading to the peatlands emitting carbon dioxide. The peatlands only stopped releasing carbon and reverted back to taking carbon out of the atmosphere when the climate got wetter again in the past 2,000 years, according to a major international study co-coordinated by the University of Leeds.
Climate change: Kilimanjaro's and Africa's last glaciers to go by 2050, says UN
2 days ago
Glaciers across the globe - including the last ones in Africa - will be unavoidably lost by 2050 due to climate change, the UN says in a report.
Glaciers in a third of UN World Heritage sites will melt within three decades, a UNESCO report found.
Mount Kilimanjaro's last glaciers will vanish as will glaciers in the Alps and Yosemite National Park in the US.
They will melt regardless of the world's actions to combat climate change, the authors say.
The report, which makes projections based on satellite data, comes as world leaders prepare to meet in Egypt for next week's COP27 climate change conference.
UN weather report: Climate woes bad and getting worse faster
Source: AP
By SETH BORENSTEIN
SHARM EL-SHEIKH, Egypt (AP) — Earth’s warming weather and rising seas are getting worse and doing so faster than before, the World Meteorological Organization warned Sunday in a somber note as world leaders started gathering for international climate negotiations.
“The latest State of the Global Climate report is a chronicle of climate chaos,” United Nations Secretary-General Antonio Guterres said. “We must answer the planet’s distress signal with action -- ambitious, credible climate action.”
In its annual state of the climate report, the United Nations’ weather agency said that sea level rise in the past decade was double what it was in the 1990s and since January 2020 has jumped at a higher rate than that. Since the decade began, seas are rising at 5 millimeters a year (.2 inches) compared to 2.1 millimeters (.08 inches) in the 1990s.
The last eight years have been the warmest on record, the WMO said in a report that didn’t break new ground but was a collection of recent weather trends, data and impacts in one central place.
"The number of delegates with links to fossil fuels at the UN climate summit has jumped 25% from the last meeting, analysis shared with the BBC shows."
'Deeply Depressing' Study Shows Planet-Warming Emissions Continue to Rise by Jake Johnson
November 11, 2022
Introduction:
(Common Dreams) Rapid and drastic cuts to global greenhouse gas emissions are necessary to curb warming and prevent the most dire climate scenarios from becoming reality.
But a new study released Friday by the Global Carbon Project finds "no sign of the decrease that is urgently needed" as emissions remain at record levels this year, with fossil fuel giants and governments plowing ahead with new extraction efforts that could push critical climate targets out of reach.
Scientists with the Global Carbon Project estimate that total CO2 emissions will reach 40.6 billion tonnes this year—driven by rising pollution from fossil fuels—and will likely continue to rise in 2023 without bold action from policymakers worldwide.
"If current emissions levels persist, there is now a 50% chance that global warming of 1.5°C will be exceeded in nine years," the researchers note. "Projected emissions from coal and oil are above their 2021 levels, with oil being the largest contributor to total emissions growth."
"The 2022 picture among major emitters is mixed: emissions are projected to fall in China (0.9%) and the E.U. (0.8%), and increase in the USA (1.5%) and India (6%), with a 1.7% rise in the rest of the world combined," the report finds.
