Climate variability leads to more intense thunderstorms • Earth.com

Climate variability leads to more intense thunderstorms In a new study by Texas A&M University, experts report that large thunderstorms in the southern Great Plains of the United States have increased in frequency and intensity. The researchers found that these changes are linked to climate variability.

“Thunderstorms in the southern Great Plains of United States are among the strongest on Earth and have increased in intensity and frequency in recent years, ”the researchers explained.

“Assessing changes in storm characteristics under different climate scenarios, however, remains very uncertain due to the limitations of the physics of climate models. “

The current study focused on isotopes from stalactites in Texas caves dating back between 30,000 and 50,000 years. The researchers analyzed the oxygen isotopes contained in the stalactites to identify trends from past thunderstorms.

“Storm regimes shift from weakly to strongly organized over millennial time scales and coincide with well-known abrupt climate changes during the last ice age,” the study’s authors found.

“Modern synoptic analysis suggests that the organization of thunderstorms in the southern Great Plains is strongly related to changes in large-scale wind and humidity patterns.”

Understanding these changes will not only help reconstruct past storm patterns, experts say, but will also help predict mid-latitude patterns that will emerge in decades to come.

“Proxy recordings are available in the southern great plains in caves,” study co-author Christopher Maupin said. “There are probably thousands of caves in the southern Great Plains and southern Texas. Why has there not been more research in these areas? Cave deposits are so promising as a proxy.

Study co-author Courtney Schumacher said scientists understand modern precipitation models. “However, we don’t know what will happen in the future, and this work will help predict storm trends in the future,” Schumacher said. Climate variability leads to more intense thunderstorms

“If we can run a climate model for the past that is consistent with the cave records, and run that same model in the future, we can have more confidence in its findings if it matches the cave records than if they were. are not. On two models, if one really matches the isotopes of the cave, you can trust that one to understand the distribution of storms in the future. “

“There are some really important questions about what has happened in the past regarding the large weather events we experience through mesoscale convective systems (large storms) versus non-mesoscale things (small storms).”

“We get so much precipitation from really big storms, and the model grids can’t capture big weather events because the grids themselves are so big. Paleoclimatology helps organize past events to develop an indirect record of how they react to average climate. “

Schumacher noted that large storms that cover hundreds of miles provide about 50 to 80 percent of rainfall in Texas.

“These thunderstorms are so big that even though most of the rain occurs in Oklahoma, the rain in Texas will still carry the isotopic signature of these huge storms,” said Maupin.

“You take fingerprints from these systems wherever they are, and they don’t need to be super-localized to be recognized. Large storms cause depleted isotope signatures. You cannot explain the variability of stalactites by temperature changes alone.

The study is published in the journal Geosciences of nature.

Through Chrissy sexton, Terre.com Editor-in-chief


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More intense and frequent thunderstorms linked to global climate variability – sciencedaily

Heavy thunderstorms in the southern Great Plains of the United States are among the strongest on Earth. In recent years, these storms have increased in frequency and intensity, and new research shows that these changes are linked to climate variability.

Co-authored by Christopher Maupin, Courtney Schumacher and Brendan Roark, all scientists from Texas A&M University’s College of Geosciences, along with other researchers, the results were recently published in Natural geosciences.

In the study, the researchers analyzed the oxygen isotopes of 30,000-50,000-year-old stalactites from Texas caves to understand the trends of past thunderstorms and their durations, using a radar calibration for the isotopes of the storms. precipitation in the region. They found that when storm regimes shift from weakly to strongly organized over millennial time scales, they coincide with well-known global abrupt climate changes during the last ice age, which occurred about 120,000 ago. at 11,500 years.

Through modern synoptic analysis, researchers have learned that thunderstorms in the southern Great Plains are strongly related to changes in wind and humidity regimes occurring on a much larger scale. Understanding these changes and various correlations will not only help reconstruct past thunderstorm occurrences, but will also help predict future mid-latitude thunderstorm patterns.

“Proxy recordings are available on the southern great plains in the caves,” Maupin said. “There are probably thousands of caves in the southern Great Plains and southern Texas. Why hasn’t there been more research in these areas? Cave deposits hold so much promise as a proxy. “

Schumacher said scientists understand modern precipitation patterns and that large storms can deplete isotopes.

“However, we don’t know what will happen in the future, and this work will help predict storm trends in the future,” she said. “If we can run a climate model for the past that is consistent with the cave records, and run that same model in the future, we can have more confidence in its conclusions if it matches the cave records than if they do not. On two models, if one really matches the isotopes of the cave, you can trust that one to understand the distribution of storms in the future. “

Caves hold little-known climatic records

Maupin, a paleoclimatologist, described the limitations that exist in capturing the true distribution of weather events over time.

“There are some really important questions about what has happened in the past regarding the large weather events we experience through mesoscale convective systems (large storms) versus non-mesoscale things (small storms),” he said. declared Maupin. “We get so much precipitation from really big storms, and the model grids can’t capture big weather events because the grids themselves are so big. Paleoclimatology helps organize past events to develop an indirect record of how they react to average climate. “

Maupin collaborated with National Taiwan University to do a uranium and thorium dating and found that the stalactites and stalagmites actually dated from the Ice Age.

Interdisciplinary collaboration

Schumacher’s expertise was needed to make connections with various rainy events that occurred over time. She had experience with radar data and global rainfall measurements.

“Large storms that cover hundreds of miles provide about 50 to 80 percent of rain in Texas,” Schumacher said. “These storms today have different isotopic signatures. “

Maupin’s research pushes back on outdated paleo-world principles, as you need to study how storms grow bigger and what influences them, he said.

“These thunderstorms are so big that even though most of the rain occurs in Oklahoma, the rain in Texas will still carry the isotopic signature of these huge storms,” said Maupin. “You fingerprint these systems no matter where they occur, and they don’t need to be super localized to be recognized. Big storms cause depleted isotope signatures. You can’t explain the variability of stalactites. with the only temperature changes. “

Research Experience for Aggie Undergraduates

Celia Lorraine McChesney ’16 and Audrey Housson ’16 were two undergraduate researchers involved in this publication, and both learned a lot through fieldwork, collaboration and the high impact learning experience.

“The cave samples have been used as a high-impact learning tool to understand the paleoclimate of Texas,” said Maupin. “One of the undergraduates started micro-milling the stalactites. I was very fortunate to have access to the resources of the College of Geosciences and to work with these talented undergraduates on groundbreaking research. “

McChesney said his experience working on his graduation thesis at the lab was “invaluable” and the research has allowed him to travel and go into the field.

“As an undergraduate research student at Texas A&M, I was proud to be part of one of the first teams to correlate climate change and weather links in a paleoclimatic dossier,” said Housson. “All this experience allowed me to discover the academic world and made me more confident as a scientist. Now, as a geologist and civil engineer, I work on heavy civil infrastructure projects like tunnels and dams related to water resources. I love how my career ties into my undergraduate research where knowing the correlation between climate change and weather helps plan water resources in the future. “

Funding for this research was provided in part by a High Impact Undergraduate Research Grant from Texas A&M University.


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Predictions of climate variability and effects on agriculture – BC Local News

As I sit down to write this, it is with the heaviness of the news that a family friend has been found deceased. This leaves those closest to you wondering what more they could have done to reach out.

Oliver Rujanschi, we will miss you and the warmth you were. Sorry friend!

And we are all moved by the tragic depth of the discovery of so many innocent children buried at Kamloops Residential School.

***

A few years ago, many of us interested in the impacts of climate change got together with the Government of British Columbia’s Climate Action Unit of the Ministry of Agriculture, to define a strategy for cope with the expected impacts.

The temperature projections for 30 years (2050) were 2.1 to 4.1 degrees Celsius in annual mean temperatures. This comes with an additional 35-64 frost-free days.

On the precipitation front, one would expect an increase of 5.1% per year and a decrease of 27% falling as snow. In all likelihood, summers will be drier.

Extremes can involve and increase the frequency and magnitude of extreme precipitation events. The average number of days above 30C will increase each year.

With this information in hand, producers and stakeholders identified the top five climate issues.

First, there has been the increased risk of forest fires. The region then experienced significant forest fire seasons in 2009, 2010 and 2012. Subsequently, 2017 and 2018 saw record fires, burning 1.1 million hectares (over two million acres ).

Second, changing hydrology affects us in the following ways: Hotter, drier summers have reduced water supplies while increasing water requirements for crops and livestock. The summers of 2019 and 2020 saw a number of farms and ranches hit hard by the flooding.

Third, increased variability was of great concern to growers, in particular: unpredictable storms, temperature / precipitation fluctuations and extremes, and freeze-thaw cycles.

Fourth, changes in pests, diseases and invasive species are upon us. Although we know the impacts of the mountain pine beetle, we do know that fire ants, cutworms and gray moth are increasingly important. This is in part due to the warmer winters.

Fifth, there will be changes in wildlife and ecological systems: the ecological communities and water resources of the Cariboo rangelands change, which alters forage productivity.

On all these fronts, producers and the government have made progress on projects.

There is much more to report and I direct interested readers to Climate Action Agriculture at www.climateagriculturebc.ca/regional-adaptation/cariboo/.

Many projects are showcased there.

Producer leaders have worked hard with governments to oversee studies and trials designed to benefit food production in our home region.

When we have the certainty of a tragedy to come, or even mere suspicion, we owe it to our fellow human beings to act. The same is true of the past and future human, personal and societal tragedies to which I alluded in my opening lines.

Soil is the skin of the Earth organism. Human health and the health of the Earth are one.

David Zirnhelt is a breeder and member of the Cariboo Cattlemen’s Association. He is also chairman of the advisory committee for the sustainable breeding program applied to TRU.

Quesnel Cariboo Observer


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Scientists study how regional climate variability affects animals in arid North America: UNM Newsroom

As visual evidence of climate change continues to shed light on a huge problem in the world, scientists studying at several National Science Foundation (NSF) Long-Term Ecological Research (LTER) sites are partly addressing the problem. problem by examining changes in the diversity and abundance of small mammals to understand their vulnerabilities to climate change.

Long-term regional monitoring can improve detection of biodiversity declines associated with climate change by combining information from both temporal and spatial dimensions. In the drylands of North America, future climate predictions include a nearly 100 percent chance of a decadal drought, the impacts of which will be magnified by ongoing global warming. Drylands are regions constrained by water scarcity and are essential for understanding how climate change affects biodiversity, as they cover 45 percent of the earth’s surface.

Ord’s kangaroo rat (Dipodomys ordii) is a grassland species present in all long-term study areas of the arid zones of our study. Like many rodent species we studied, D. ordii’s responses to drought conditions varied among sites and ecosystem types. Photo credit: Nicole Kaplan

In a study published today in Global Change Biology titled “Decline in rodent abundance and diversity follows regional climate variability in the drylands of North America“, a group of scientists are trying to understand long-term changes in the diversity and abundance of small mammals and identify species that may be most sensitive to our drier, less predictable climate.

“Over the past 100 years in the southwestern United States, our climate has become drier and more variable, with increasing differences in drought index from year to year.” said Jennifer Rudgers, professor of biology at the University of New Mexico, senior author. and director and principal investigator of the Sevilleta Long Term Ecological Research (SEV LTER) Program in New Mexico. “Increasing climate variability is an aspect of climate change that has not been studied as extensively as changes in average temperature such as the climate becoming, on average, warmer or drier. Yet most climate predictions for the future include the prediction of increasing variability. ”

As part of the study, scientists analyzed abundance data from 22 rodent species in grassland, scrub, ecotone, and forest ecosystems in the southwestern United States as part of a time series (1995-2006 and 2004-2013) representing the Pacific phases. Decadal oscillation (PDO). PDO influences drought in southwestern North America, where rodents are diverse and important consumers.

The study, which took place at LTER sites from the northern Chihuahuan Desert to the southern Great Plains of western North America, combined 12 datasets on eight ecosystem types to examine the models. temporal diversity, composition and abundance of rodent species at the regional scale.

Data gathering

Sevilleta National Wildlife Refuge Branch Fellows Ariel Elliott is recording data on a kangaroo rat. Photo credit: Kathy Granillo

“Long-term observations that occur during periods with varying climates have allowed us to look for non-linear relationships between mammalian abundance and climatic variables,” Rudgers explained. “Non-linearities give signals about the sensitivity of species to climate variability. Because our climate is quite variable, we could capitalize on this inherent variability to detect past patterns that can predict the future. “

A key element that impacted the study was the Pacific Decadal Oscillation (PDO) and the role it plays in climate change. PDO is a climatic phenomenon that occurs when the sea surface waters in the northern Pacific Ocean fluctuate in temperature. This is an often decades-long oscillation that affects precipitation in the southwestern desert. When the surface temperatures of the Pacific Ocean along the west coast of North America are warm, the southwestern United States is generally in a phase of drought. When surface waters are cool, they tend to be wetter in the southwest.

“Because we had long-term small mammal abundance datasets (almost 20 years of data), we were able to separate our dataset into two time periods that each covered a phase of AOP: one wetter and earlier period in the mid-1990s-early 2000s and a drier, later period (2004-2013), ”said Rudgers. “This allowed us to explore how the climatic sensitivities of small mammals have changed over time, in concert with different phases of AOP.”

Using a climate sensitivity function approach developed by the team, scientists were able to comb through long-term observations that occurred during periods with varying climates to look for non-linear relationships between the abundance of mammals and climatic variables.

WER1 stamp

UNM is the only R1 in New Mexico: doctoral university with very high research activity as classified by the Carnegie Commission on Higher Education.

“We detected regional trends in our New Mexico, Colorado, and Arizona data sets,” Rudgers said. “Regionally, the diversity of rodent species has declined by 20 to 35 percent, with greater losses in the subsequent period. The abundance has also declined regionally, but only recently, with losses of 5 percent of the animals we have captured and released.

However, Rudgers noted that these declines in diversity varied across ecosystem types and locations. “The greatest declines in diversity have occurred in three types of ecosystems: the juniper pine forests and creosote shrub areas of the Sevilleta National Wildlife Refuge in New Mexico and the mixed shrub areas of salt bush on the Shortgrass Steppe LTER site in Colorado.

“The declines in abundance that we observed and the sensitivity of mammals to climatic variables were highly dependent on the ecosystem and location that we studied,” said Rudgers. “Thus, sensitivity to climate change was not at all consistent across a species’ range. In fact, the identities of winning and losing species differed between ecosystems for 70 percent of the taxa. This means that we need to take the local environment into consideration when making predictions about species vulnerabilities. “


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The Great Plains facing climate variability

Mother Nature has provided increasingly erratic rainfall for the Great Plains over the past decade, affecting grasslands, forage systems and cattle production in the region – and scientists expect this trend to continue. intensifies.

Cow / calf operations in the Great Plains are likely to be affected by the increased variability in rainfall which supports forage production for 50% of the country’s cow herd. (Photo by Texas A&M AgriLife)

Texas A&M AgriLife Research scientists and collaborators explored the rural economic impacts of climate variability and identified potential future outcomes for beef cattle production in a research article, “Future climate variability will challenge range beef production in the Great Plains», Recently published in the journal Golf courses.

David Briske, Ph.D., AgriLife Research pathway ecologist in the Department of Ecology and Conservation Biology in the College of Agriculture and Life Sciences To Texas A&M University, Bryan-College Station, was the principal author. The co-authors were John Ritten, Ph.D., University of Wyoming; Amber Campbell, Ph.D., Kansas State University; Toni Klemm, Ph.D., postdoctoral research associate at AgriLife Research; and Audrey King, Ph.D., Oklahoma State University.

The researchers concluded that the key to sustainable beef cattle production in the Great Plains is to prepare for climate change in the region rather than react to climate change and hope their article can guide discussions and encourage future actions. .

Growing climate variability in the Great Plains

Climate change is often seen as a long-term gradual change in weather conditions, such as precipitation and temperature. But future weather conditions in the Great Plains may be characterized by increased variability in precipitation, or increased cases of wet or dry years and less “normal years,” Briske said.

The increased variability in rainfall will have far-reaching consequences for the region, but agriculture and rural economies could be the most vulnerable, Briske said. Cattle farms, which depend on grassland fodder for a large portion of their animals’ feed intake, could be particularly vulnerable to increased variability in rainfall.

The Great Plains contain the largest expanses of grassland remaining and 50% of the country’s beef cows, over 16 million head, representing the main components of the region’s overall agricultural economy. Beef cattle production contributed $ 43 billion to state and local economies on the Great Plains in 2017.

In Texas alone, beef cattle and calves generate the largest total contribution among the state’s agricultural products – $ 8.566 billion in cash receipts alone, according to a 2020 study. Texas A&M Agricultural Extension Service economic impact study focused on food and fiber production.

Highest precipitation variability in the southern Great Plains

A key impact of the increased variability in rainfall is on grassland forage production which supports cow / calf production throughout the region. Researchers are examining past, present and future climate projections and the consequences that increased variability could have on sustainable beef production.

“The focus has been on the change in total annual precipitation, but what is most striking is the increase in interannual variability – the phenomenon where we go from a few years drier than normal to flooding. , then to a drought. and so on, ”Briske said.

It’s important to recognize that it’s different from just dealing with drought, he said.

“I don’t mean to be alarmist, but we want to present this message in the context of agricultural production so that the industry can prepare to offset the impact of greater climate variability on individual producers, grassland conservation and rural economies. “

Research indicates that the number of forage shortage years for the southern plains, which include Texas, Kansas, and Oklahoma, has dropped from two years per decade to three years, four months per decade, and has remained at two years. for the northern plains. The number of years of abundant forage increased from two to five years per decade on the northern plains and from two to three and a half years on the southern plains by the turn of the century.

This indicates that beef producers will experience a greater number of years where annual feed production can vary by 50%. This increases the already difficult task of balancing forage production with demand for livestock. Briske said this increasing weather variability could present sustainability issues for beef cattle operations and regions that have been successful in the past.

This variability will negatively impact the economic viability of beef cattle production and the sustainability of grasslands by creating overgrazed conditions, he said. But effective adaptations that could help cattle producers minimize the impacts require more consideration.

Further slaughter and liquidation of cattle herds during drought years and then restocking in normal or wet years creates the greatest economic hardship for beef producers, Briske said. The researchers highlighted the need for adaptations that will minimize overgrazing of prairies and the need to undergo costly destocking-restocking cycles as being the most critical.

But current climate adaptations, including appropriate stocking rates for conservative grazing, grass reserves, and water development, may be insufficient to compensate for the negative economic impacts of future rainfall variability, a t -he declares. Research suggests that beef cattle production may gradually shift from southern plains states like Texas to the central and northern plains.

For example, Briske said, the Dakotas and Nebraska gained 403,000 cows between 2010 and 2020, while Texas lost 570,000.

It’s earlier now

The researchers stressed the need to act as early as possible and integrate ideas from several sectors of society outside of agriculture to support sustainable beef production in the grasslands.

The action begins by shifting the stakeholder perspective towards a proactive rather than reactive response to severe weather events like drought and flooding, Briske said. Preparedness will require anticipating threats to the sustainability of beef cattle production in the Great Plains at both macro and micro scale.

Southern Plains beef producers were surveyed as part of this research. The majority indicated that they were aware, but uncertain, of future climate impacts, which suggested they would benefit from assistance in developing and implementing appropriate adaptations, Briske said.

Suggesting stakeholders to act now rather than wait for the crisis, he said initial conversations about the potential impacts of increasing climate variability could be led by trade groups and the beef industry. which have political weight at all levels of government. Beef and ranching industry coalitions could make lawmakers aware that changes in state and federal policies regarding sustainability in future climates should be a top priority now and in the future. .

“The key is to start planning and investing in coping strategies during the good years,” he said. “The region is likely to experience an increasing number of wet and dry years in the future. The question is whether industry and rural areas will be prepared.

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Society’s positive response to past climate variability is an example for today

By Mikayla Mace Kelley, University Communications

March 24, 2021

Ruins of Late Antiquity villages in the limestone massif of Syria: rural settlements in the Roman and Sassanid Near East developed during the Little Ice Age of Late Antiquity.
Artur Rodziewicz

As the signs of man-made climate change become increasingly alarming, research into how past societies have responded to natural climate change becomes increasingly urgent. Researchers have often argued that climate change plunges communities into crisis and creates conditions that lead societies to collapse, but a growing body of research shows that the impacts of climate change on past populations are rarely so straightforward.

In a new paper published in Nature, researchers in archeology, geography, history and paleoclimatology present a framework for research on what they call “the history of climate and society”. The framework uses a series of questions to address common issues and biases in climate history studies and requires researchers to consult or include in their work researchers from various scientific, social, and humanistic disciplines.

“There is a long history of researchers focusing too much on making connections between climate variability and the collapse of civilizations. We want the field to move away from collapse and study the full spectrum of responding to climate variability, and that includes resilience and innovation. »Said co-author of the study and paleoclimatologist Kevin Anchukaitis, associate professor at the University of Arizona School of Geography, Development and Environment.

Lead author of the study, Dagomar Degroot, associate professor of environmental history at Georgetown University, said: “With this framework, we hope to help other researchers find more diverse links between climate and society, which we hope will lead to a more realistic understanding of the past. and a better guide for the future. “

Anchukaitis’ experience in using past climate data from tree rings, sediments, corals, and other indirect measures allowed the research team to more precisely combine the data with evidence from ancient documents. and artefacts from various case studies described in the article. Anchukaitis said the team itself is an example of what researchers would like to see more of in climate and archaeological research: equitable collaboration between different fields.

Using the newly developed framework, the researchers assembled case studies of societies that have adapted to two of the most frequently studied periods of climate change: the Little Ice Age of Late Antiquity in the 6th century and the Little Ice Age. from the 13th to the 19th century. Although these two periods imposed hardship on many communities, the case studies reveal that populations have adapted by exploiting new opportunities, relying on resilient energy systems, relying on resources provided by trade, responding effectively to disasters or migrating to new environments.

An example of this resilience can be seen in societal responses to climate change in the Eastern Mediterranean under Roman rule. Environmental reconstructions show an increase in winter precipitation beginning in the fifth century and continuing until the end of the Little Ice Age of Antiquity. Pollen data and archaeological studies reveal that cereal agriculture and pastoral activities have flourished due to increased rainfall, with many settlements increasing in density and area. Regional economic practices allowed goods to flow easily between communities, bringing the benefits of increased agricultural production to consumers. Meanwhile, the elite of society invested in market-oriented agriculture and funded the construction of dams and other infrastructure that enabled farmers to manage water more efficiently.

Although the climate changes experienced by past societies have been of less magnitude than the changes we are currently facing, case studies show that communities and societies have often adapted and persisted during periods of climate variability, a said Anchukaitis.

With a research framework that takes into account the heterogeneous effects of past climate change and the challenges of interpreting historical sources, the study authors hope that future research on the history of climate and society will identify examples of previously neglected resilience and will contribute to efforts to adapt to the unprecedented global warming facing societies today.

“Humans are not passive victims of climatic shocks,” Anchukaitis said. “How these events affect societies, economies and cultures depends on how we respond to them. How well prepared and flexible are we in the face of climate change? “


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Climate variability and pandemic – creating insecurity



| Update:
March 16, 2021, 8:15 p.m.


Currently, in many parts of the world, environmentalists are referring to a 2018 United Nations security resolution that warned of the adverse effects of climate change, ecological changes and natural disasters. This warning is now being realized through what is happening particularly in Africa which is experiencing droughts, desertification, land degradation and food insecurity in different countries. Sudan, in particular, has become an example of vulnerability due to increased frequency of droughts and high variability in rainfall. This affects rural areas where the livelihoods of pastoralists play a dominant role.

Such distressing situations also appear in other parts of the world – in Latin America, Asia and also in different parts of Australia. Women, youth and children are the groups most affected by such climate insecurity. This is particularly evident in South Asia, India and Bangladesh.

Such momentum, according to Nisreen Elsaim, Sudanese climate activist and chair of the United Nations Secretary-General’s Youth Advisory Group on Climate Change, also creates climate-related emergencies that not only lead to major disruptions in healthcare. and climate-related internal migration, but also increased risk of gender-based violence. It is becoming evident that women, youth and children are the groups most affected by climate insecurity.

This renewed interest in the effects of climate variability came to the fore ahead of the 26th United Nations Conference of the Parties on Climate Change (COP26) scheduled to take place in November this year in Glasgow, Scotland.

Nature historian Sir David Attenborough, in a video message, also issued a strong warning that “the stability of the whole world” could be altered by climate threats. In this context, he drew attention to emerging threats of an “unprecedented nature”. He also stressed that climate change ignores national borders and turns forests into deserts, drowning large cities and leading to “the extermination of a large number of creatures with whom we share our planet”.

UN Secretary-General António Guterres has also drawn attention to the fact that the last decade has been the hottest in human history and that forest fires, cyclones and floods are now become the new normal within communities. It is also starting to affect political, economic and social stability. He also stressed that “climate change is an amplifier and a multiplier of crisis” because it also dries up rivers, reduces harvests, destroys critical infrastructure and displaces communities.

It can be noted that during the recent discussions in the last week of February at the UN and in some of its institutions, including UNEP, a consensus emerged that 2021 will be critical, not only to curb the rapid spread. of the COVID-19 pandemic, but also to respond to the impact created by climate variability. It is also a climate challenge. Guterres also reiterated the need to create a global coalition for carbon neutrality by 2050. It is hoped that such a step will also help contain growing pollution in the atmosphere.

Likewise, the United Nations Economic and Social Commission for Asia and the Pacific (ESCAP) has reminded us that sustainable energy in the form of a reliable and uninterrupted energy supply is essential to manage the various impacts that the world is facing. is facing due to the pandemic crisis.

Armida Salsiah Alisjahbana, Under-Secretary-General of the United Nations and Executive Secretary of ESCAP, noted some interesting aspects of this paradigm.

Attention was drawn to the fact that clean and sustainable energy is essential to our recovery from the COVID-19 pandemic. The SDGs in this regard could then be a guiding framework to better get back together:, decent work, poverty and inequalities, to name a few, and (b) by directing stimulus spending towards investments in renewable energy and energy efficiency projects.

This will then help create more jobs for the same investment as fossil fuel projects. By increasing spending on clean cooking and access to electricity, we can also improve economic activity in rural areas and introduce modern infrastructure that can make communities more resilient and inclusive, especially for the good- to be women and children. You have to agree with such a format.

In addition, investing in low-carbon infrastructure and technologies can create a platform and base for achieving ambitious climate commitments reached in the Paris Agreement that sets targets for a warming limit. climate of 2 degrees.

Therefore, it was interesting to note that during the February discussions, several countries announced their desire to achieve carbon neutrality, in line with the targets set out in the SDG matrix. We must understand that we must harness the capacity of sustainable energy to rebuild our societies and economies while protecting the environment in pursuit of the 2030 Agenda for Sustainable Development.

Reference should also be made here to the decision of the new US administration Biden to join the Paris Agreement. It’s not just symbolic. It has powerful and political significance for COP-26. President Biden signed a letter in this regard on his first day in office. The connotation of returning to Paris, according to environmental analysts, means that now the United States will have to follow the rules again. These rules mean that this year the United States will have to improve on its previous pledge to cut carbon emissions made in the French capital in 2015. It can be mentioned that President Biden has pledged to achieve net zero emissions by 2050 and 100 percent clean electricity by 2035. This equation will now guide the US economy and society for decades to come. Coming back to Paris also means that it is no longer “America First”. He also reiterates the fact that “multilateralism” is once again present in the White House.

This change in US policy is quite understandable. The world has watched in horror the many wildfires in California. These have been associated with climate change. There have also been numerous forest fires in Australia and South America. These incidents sent a clear message: the climate now plays an important role in security policy. President Biden’s cancellation of the Keystone XL pipeline permit was also a carefully calculated message to the oil industry.

It should be understood that the United States has once again become a party to the multilateral effort to overcome the existential threat posed by climate change. Along with the pandemic, the economy and racial justice, it has now become one of the four key crises facing the new administration.

He also clearly understands that tackling the root causes of rising temperatures can not only benefit other pressing issues, but also that there is symbiotic connectivity in this regard. The action plan also made it clear that responsible authorities in the United States understand that climate solutions can boost the economy and also generate jobs.

It should be remembered that during his campaign for the presidency, Biden focused on electric vehicles and charging infrastructure (necessary in this regard), the construction of high-speed railways and the improvement of energy efficiency in homes and offices. Many suggest that all of this could be difficult to achieve quickly. However, it is also mentioned that to achieve this goal, the Biden team could push the US Congress to adopt a clean electricity standard that would set a target for green power, but leave it to utilities to find the best. way to achieve the goal. .

Former Secretary of State John Kerry will serve as President Biden’s special envoy on climate change. His presence will help move things forward not only for the United States but for the rest of the world as well.

It would also be appropriate at this point to refer to some of the views expressed regarding the impact of climate variability by Joyce Msuya, Deputy Executive Director of the United Nations Environment Program (UNEP). He rightly pointed out that environmental issues are development issues and are therefore everyone’s concerns.

In this regard, attention was also drawn to the fact that biodiversity loss is not only happening at a faster rate than ever before, but also pollution, especially plastic pollution, is emerging as a big problem.

In this regard, UNEP has rightly proposed that “environmental problems are development problems and they are everyone’s problems”. Citizens, as such, have been urged to make small changes in their households. It was also highlighted that communities, especially those who live around the oceans, can make small changes when it comes to their waste management to help improve the blue economy. It was also significantly suggested that governments need to work with the private sector, indigenous communities, civil society, the youth population and children to deal with environmental change. This means that inclusive multilateralism is the answer to our problems. We have to pay more to protect nature than to exploit it.

António Guterres correctly described how the world is facing a grave and grave situation. Apparently, in the current growth trajectory “despite a temporary drop in emissions due to the pandemic, the earth is heading towards at least 3 ° C of global warming this century; more than one million of the estimated 8 million plant and animal species are at significantly increased risk of extinction; and diseases caused by pollution currently kill some 9 million people prematurely each year.

Muhammad Zamir, former ambassador, is an analyst specializing in foreign affairs, the right to information and good governance.

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Antarctica is melting faster than models predict due to climate variability • Earth.com

Decreasing ice levels in Antarctica, as well as future sea level rise, have been underestimated. In a new study by State of pennsylvania, the researchers found that existing models do not take into account climate variability, which has a significant influence on the Antarctic ice sheet.

“We know that ice caps are melting as global temperatures rise, but uncertainties remain about the extent and speed of this melting,” said study co-author Professor Chris Forest. “Our results shed new light on an area of ​​uncertainty, suggesting that climate variability has a significant impact on melting ice caps and sea level rise.”

Before accounting for climate variability, experts found that models predicted sea level rise of about 10.6 to 14.9 inches by the end of this century. When climate variability was incorporated into the models, these predictions increased to 4.3 inches.

“This increase alone is comparable to the amount of sea level rise that we have observed over the past decades,” said Professor Forest. “Every element adds to the storm surge, which we expect to see during hurricanes and other severe weather events, and the results can be devastating.”

It takes thousands of simulations to project how the Antarctic ice sheet will evolve under future climatic conditions. Scientists use the average temperature that is derived from all of these results.

However, the process mitigates peaks caused by climate variability and reduces the average number of days above temperature thresholds that can impact the melting of the ice sheet, creating a bias in the results, the scientists said. .

“If we include the variability in the simulations, we will have more hot days and more sunshine, and so when the daily temperature exceeds a certain threshold, it will melt the ice,” said Prof Forest. “If we only operate in average conditions, we don’t see these extremes happening on annual or decadal timescales. “

To study the effects of climate variability, scientists incorporated relevant atmospheric and oceanic data into a three-dimensional model of the Antarctic ice sheet. The analysis showed that atmospheric variations had a significant impact on the ice sheet with immediate effects. The variability of ocean temperatures was found to have a smaller, but significant impact.

Results from previous studies suggest that warming oceans could cause large pieces to break apart, exposing massive ice cliffs that would collapse under their own weight.

According to experts, model simulations that did not include the effects of climate variability delayed the retreat of the ice sheet for up to 20 years and underestimated future sea level rise.

“This additional melting ice will impact hurricane storm surges around the world. Additionally, for years, IPCC reports have looked at sea level rise without taking into account this additional variability and underestimated the potential impact, ”said Prof Forest. “It is important to better understand these processes that contribute to the loss of additional ice because the ice caps are melting much faster than expected. “

The study is published in the journal Climate dynamics.

By Chrissy sexton, Terre.com Editor-in-chief


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humans have faced a lot of climate variability


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The climate explained is a collaboration between The Conversation, Stuff and the New Zealand Science Media Center to answer your questions about climate change.

If you have a question you would like an expert to answer, please send it to [email protected]


How much climate variability have humans faced since we evolved and since we began to settle (Neolithic times)? How important was migration to human survival during these times?

The climate always fluctuates because the variation in heat from the Sun reaching the Earth causes glacial-interglacial cycles. Over the past 420,000 years, there have been at least four major transitions between ice ages and relatively warmer interglacials.

Modern humans emigrated from Africa to populate the rest of the globe between 120,000 and 80,000 years ago, which means our species has had to adapt to many massive climate transitions.

Heating and cooling

The Last interglacial 129,000 to 116,000 years ago, it was a period of intense global warming (from about 2 ℃ more than today to as much 11 ℃ higher in the Arctic), resulting in a sharp reduction in the ice caps of the Arctic, Greenland and Antarctica, and a sea level rise of 6 to 9 m.

The front of a glacier that breaks and falls into the sea.
Arctic glaciers have already melted.
Flickr / Kimberly Vardeman, CC BY

The last ice maximum of 26,500 to 19,000 years ago coincided with a significant drop in atmospheric CO₂ and a global cooling of 4.3 ℃.



Read more: The climate explained: will the tropics eventually become uninhabitable?


Low temperatures turned much of the world’s water to ice and enlarged glaciers.

This drop in sea level up to 130m compared to today. These exposed continental shelves joined land masses and created vast coastal plains, such as Beringia which linked Russia to North America, and Sahul which linked Australia to New Guinea.

After a brief period of warming, the northern hemisphere abruptly returned to near-glacial conditions about 12,900 years ago which lasted for 1,300 years. Known as the Younger dryas, this period recorded a climatic cooling down to 15 ℃ and the giant ice caps have advanced again. The end of the Young Dryas was just as brutal, marked by a rapid warming up to 10 ℃ in a few decades.

The most recent period of climate instability was the transition from Medieval Hot Period to the Little Ice Age. Cold conditions between 1580 and 1880 were characterized by a 0.5-4 ℃ cooling and expanding mountain glaciers in the European Alps, New Zealand, Alaska and the Andes.

An oil painting showing a winter landscape with many people ice skating.
Winter Landscape with Skaters by Hendrick Avercamp in 1608 is one of the many works of art that depict the cold of winter during the Little Ice Age.
Wikimedia / Rijksmuseum Amsterdam

What climate change meant for humans

Despite our impressive ability to adapt to a wide range of environments, humans have a privileged environmental envelope in which we thrive. These conditions would have been characterized by a mixture of open savanna-type forests, wetlands and rocky habitats.

Dense, humid tropical forests made access to resources difficult, while deserts were often too dry to provide enough food and materials.

The climatic conditions of the last interglacial could have encouraged waves of human expansion outside Africa when a humid and hot climate favored vegetated corridors across Eurasia.

The ensuing cooling period connected land masses previously separated by oceans and allowed human travelers to access Sahul from the Indonesian archipelago.



Read more: An incredible journey: the first people to arrive in Australia came in large numbers, and on purpose


Entering America from Asia via Beringia was more difficult because humans only got there during the last ice maximum when a huge ice cap blocked the new land bridge.

Meanwhile, human populations decreases and contracted to small shelters until the climate of eastern Beringia began to warm again 17,000 to 15,000 years ago.

This warming created new accessible routes along the Pacific Northwest, followed by another ice-free corridor that formed 3,000 years later when the ice sheet retreated.

The need for food

Due to the cold temperatures and the scarcity of food at this time, humans had to improve their hunting efficiency by targeting large animals to maximize the return of food.

In the southern hemisphere, modern humans had already lived in Australia for 30,000 to 40,000 years before the last glacial maximum, so such drastic cooling and drying likely pushed human populations decline and retreat to smaller refuges closer to reliable sources of fresh water where game also congregated.



Read more: Did man or climate kill megafauna? In fact, it was both


After the last ice maximum, modern humans continued to spread across North America. The warmer and wetter climate of the southern hemisphere has also contributed to human migration to South America.

At the same time, the young Dryas of the northern hemisphere forced the populations either to return to a nomadic way of life, or to take refuge in a few hospital areas. After the harsh conditions of the Younger Dryas, the first testimony of agriculture have emerged in various parts of the world.

The settlement of remote Oceania between 3,500 and 730 years ago required ocean voyages of thousands of kilometers across the Pacific to New Zealand temperate and subantarctic waters.

A warm sunrise over the New Zealand coast
Global warming has created conditions that have favored migration across Oceania, including to New Zealand.
Flickr / Domen Jakus, CC BY-NC

Although these migrations are not clearly linked to any of the previous climate change events, the wind regimes at the time were particularly sailing friendly.



Read more: Climate Explained: Sunspots Affect Our Weather A Little, But Not As Much As Other Things


But the Little Ice Age could have reduced the size of the population and pushed the first Maori settlements north.

The Little Ice Age probably hit people in the northern hemisphere much harder. The cold climate caused many poor harvests, famines and population declines.

In the past five years alone, Earth is already ~ 1.1 ℃ hotter than 150 years ago and temperatures should be + 4.5 ℃ more than today by 2100. Today, we live in the hottest climate since our species began to populate the globe.

Climate fluctuations that lasted for millennia now occur in less than 100 years, affecting freshwater availability, food supply, environmental health and integrity.

Past climate change has paved the way for people to demonstrate immense adaptability and resilience by developing new skills, agricultural techniques, business models and political structures, but above all by abandoning their old unsustainable lifestyles.


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Is climate variability organized? – Eos

One fascinating aspect of the climate system is that its variability is governed by simple mathematical relationships. A recent paper in Geophysics Reviews explains how these mathematical relationships — in the form of power laws– structure a large part of climate variability in terms of time, space and intensity. Understanding how climate variability is structured helps us make robust climate reconstructions and skillful future predictions. Here, two authors give a brief overview of what a power law is, how it can be used to improve our understanding of the climate system and the physical mechanisms behind it.

How are the different aspects of the climate system interrelated?

Climate variables, such as temperature, precipitation, total ozone, relative humidity, and sea level change, are highly interconnected, both over long periods of time and over great spatial distances. It shows in the datasets: there are correlations in the averages of the data over long intervals or between distant areas.

The majority of correlations in climate can be described by a simple mathematical relationship called a “scale”.

An interesting conclusion is that the majority of correlations in climate can be described by a simple mathematical relationship called a “scale,” which says that the means at different scales are related by a simple mathematical function: a power law.

In practice, this means that, for example, the duration of temperature fluctuations increases systematically, as the temperature fluctuation increases.

In addition, the likelihood of an event occurring also decreases as the event becomes intense. This is similar to Richter’s Law for Earthquakes, which says small earthquakes happen very often while very large earthquakes rarely happen.

Diagram of the relationship between the time scales of typical climatic phenomena and their spatial scales. Credit: Naiming Yuan

How can mathematical tools be applied to understand these relationships?

Figure (a) shows the daily precipitation in Xichang, China and (b) shows its intensity probability distribution. Figure (c) shows the annual average temperature time series of central England (black line) as well as its non-linear trend (red line) and long-term fluctuations using two different methods (blue and magenta lines) ). Figures (d) and (e) show two ways of measuring the scaling properties of the central England temperature time series ((d) Trendless Fluctuation Analysis and (e) Function of autocorrelation). Credit: Franzke et al. [2020], Figure 1

Power laws appear as straight lines in graphs where both axes have a logarithmic scale and the slopes indicate the exponents of the scale. They are familiar to many scientists in undergraduate physics classes.

A well-known example is the relationship between the angular frequency of a pendulum and its length: the angular frequency is proportional to the inverse square root of the length.

Another example is how the gravitational force between two bodies depends on their distance from each other: the gravitational force is proportional to the inverse of the distance squared.

It is fascinating that power laws also exist in climate time series, as shown in the graphs to the right, where scale exponents measure the persistence of climate anomalies and the likelihood of extreme events of different intensity.

Which climatic variables exhibit scaling behavior?

Scaling behavior is pervasive in the climate system. It has been detected in many climatic variables, using in situ observation recordings, paleo-reconstructions and model simulations.

Most important is the surface air temperature, where the most pronounced scaling behavior is found in oceanic and coastal regions, as shown in the map below. However, other variables such as precipitation, river runoff, ozone levels, humidity, and sea level height also have this property, suggesting that scale is a very common feature. of the climate system.

What are the physical mechanisms behind the scaling?

There are a few possible climate system-wide explanations, all caused by the underlying non-linear nature of the equations of motion. A great example is turbulence: the scaling behavior in which energy is distributed between spatial scales was discovered by AN Kolmogorov in 1941.

The timescale can be explained by the nonlinear nature of the equations governing the climate system and the interaction of components of the climate system with different timescales such as the atmosphere (with a typical timescale ranging from a few seconds to a few weeks), the ocean (with time scales from weeks to decades) and ice caps (evolving over time scales ranging from decades to millennia).

How can scaling be applied to improve climate modeling and forecasting?

Using scaling allows us to more quickly calculate the Earth system’s response to greenhouse gas emissions and improve our understanding of predictability and climate models. Recently a Seasonal to interannual stochastic prediction system was developed with this in mind. Its forecasting accuracy compares favorably with long-term operational forecasting models based on traditional climate models.

What are some of the unresolved questions that require additional research, data or modeling?

Through scale analysis, we now have a better understanding of the climate system and appreciate that it consists of different time scales characterized by different scale relationships. While for the weather (up to 2 weeks) and climatic (over 30 years) time scales, the variability increases sharply with the time scale; this is not the case for the intermediate periods (2 weeks to 30 years) where the increase is quite small. How this affects predictability on these timescales is an open question. It should be noted that an inclusion of scale behaviors in traditional climate models may also be useful (e.g. for improving sub-network scale parameterizations), but more effort is still needed to this regard.

How far scaling can help rebuild the past climate is another area of ​​ongoing research. Scaling of paleoclimatic data has received a lot of attention and has been used to assess how well climate models reproduce observed long-term climate variability. While the variability of global average temperature on interannual to millennial time scales appears to be consistent between climate models and climate reconstructions, the large gap in slow climate variability at regional scales calls for further research on temporal structures and of climate variability as well as on improving the interpretation and quality of paleoclimatic records. The PAGE group “Climate variability across scalesIs currently working on this issue.

A better appreciation of how scale relates climate variability at different scales has already improved our understanding of the climate system, but there is still a lot of exciting theoretical and applied work to be done in this area.

—Christian LE Franzke ([email protected]; 0000-0003-4111-1228), University of Hamburg, Germany; and Naiming Yuan ( 0000-0003-0580-609X), Institute of Atmospheric Physics, Chinese Academy of Sciences, China

Quote:

Franzke, CLE, Yuan, N. (2020), Is climate variability organized ?, Eos, 101, https://doi.org/10.1029/2020EO145366. Posted on June 11, 2020.

Text © 2020. The authors. CC BY-NC-ND 3.0
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