NCAR Director James Hurrell accepts prestigious chair at CSU

BOULDER, Colo. — James Hurrell, who has served as director of the National Center for Atmospheric Research (NCAR) since 2013, has accepted a position as the Walter Scott Presidential Chair in Environmental Science and Engineering at Colorado State University. He will take on his new responsibilities in September. Hurrell, an expert in climate variability and change, first came to NCAR in 1990 as a visiting scientist. He later served as director of two NCAR laboratories and chief scientist of the Community Earth System Model (CESM). The University Corporation for Atmospheric Research (UCAR), which manages NCAR on behalf of the National Science Foundation, will conduct an international search for a new director. "My sincere thanks to Jim for his steady leadership of NCAR since 2013 and for all he has done for the organization during his 28-year tenure," said UCAR President Antonio Busalacchi. "His appointment to a presidential chair at Colorado State University is a prestigious honor, and CSU could not have chosen a better leader to fill this role." For more on Hurrell's new position, see the CSU announcement.

UCAR, Skymet team up to improve forecasts in India

BOULDER, Colo. — A major new partnership between the University Corporation for Atmospheric Research (UCAR) and Skymet Weather Services will provide people across India with more detailed and accurate forecasts.The $1 million agreement will enable Skymet to use a customized version of the DICast® system, cutting-edge automated weather prediction technology developed at the National Center for Atmospheric Research (NCAR). DICast uses advanced statistical techniques to blend output from different weather models with observations and statistical datasets, generating dynamically tuned predictions for specific sites that are more accurate than those based on a single model and traditional statistical approaches.This will result in improved forecasts for residents throughout India, including tens of millions of farmers, business executives, and emergency officials. The information will help strengthen business competitiveness while providing vulnerable communities with early warning of floods and other disasters."This investment by Skymet is a commitment to the science enabled by UCAR and the role it plays in protecting lives and property in the United States and around the world," said UCAR President Antonio Busalacchi. "We look forward to a long-term and fruitful relationship with Skymet, producing broad benefits to the people of India."Skymet, based outside New Delhi, provides weather forecasts and graphics to Indian media organizations and customized predictions to the nation's agricultural, insurance, energy, and other vital sectors of its fast-growing economy.Skymet founder and CEO Jatin Singh (left) and UCAR President Antonio Busalacchi shake hands after signing an agreement that will lead to improved weather forecasts across India. (©UCAR. Photo by Carlye Calvin. This image is freely available for media & nonprofit use.)"We're honored to work with UCAR on this very important endeavor, which will enable us to bring the most advanced products and weather services to the people of India," said Jatin Singh, Skymet's founder and CEO. "This agreement provides us access to the best technology in the world. The forecasts that result will save lives and increase the productivity of farmers and businesses."Singh added that he looks forward to future collaborations with UCAR.William Mahoney, director of the NCAR lab that developed DICast, said the five-year agreement will enable his team of scientists and engineers to focus on improving forecasts of tropical weather patterns, including monsoons. DICast has been applied globally, but has primarily been used for forecasts in midlatitude regions."This opens up research opportunities for better understanding tropical weather patterns," Mahoney said. "It will enable us to expand our support of the U.S. and global weather industry and provide additional benefits to society."James Cowie, an NCAR software engineer who helped develop DICast, added that Skymet's extensive observations of atmospheric conditions throughout India will provide important information for future forecasts."Skymet has a huge weather observing network in India, and we plan to incorporate their data into the DICast system," Cowie said. "This will improve both short and long-range forecasts of weather conditions and will enable the forecasts to zoom in on scales of less than 1 kilometer."Founded in 2003, Skymet is India's largest weather monitoring and agriculture risk solutions company.DICast is a registered trademark of the University Corporation for Atmospheric Research.

Record-breaking ocean heat fueled Hurricane Harvey

BOULDER, Colo. — In the weeks before Hurricane Harvey tore across the Gulf of Mexico and plowed into the Texas coast in August 2017, the Gulf's waters were warmer than any time on record, according to a new analysis led by the National Center for Atmospheric Research (NCAR).These hotter-than-normal conditions supercharged the storm, fueling it with vast stores of moisture, the authors found. When it stalled near the Houston area, the resulting rains broke precipitation records and caused devastating flooding."We show, for the first time, that the volume of rain over land corresponds to the amount of water evaporated from the unusually warm ocean," said lead author Kevin Trenberth, an NCAR senior scientist. "As climate change continues to heat the oceans, we can expect more supercharged storms like Harvey."Despite a busy 2017 hurricane season, Hurricane Harvey was more or less isolated in location and time, traveling solo over relatively undisturbed waters in the Gulf of Mexico. This gave Trenberth and his colleagues an opportunity to study in detail how the storm fed off the heat stored in that 930-mile wide ocean basin.The team compared temperatures in the upper 160 meters (525 feet) of the Gulf before and after the storm using data collected by Argo, a network of autonomous floats that measure temperature as they move up and down in the water. To measure rainfall over land, the scientists took advantage of a new NASA-based international satellite mission, dubbed Global Precipitation Measurement.The study appears in the journal Earth's Future, a publication of the American Geophysical Union. It was funded by the U.S. Department of Energy and by the National Science Foundation, which is NCAR's sponsor. Other co-authors of the paper are Yongxin Zhang and John Fasullo, also of NCAR; Lijing Cheng, of the Chinese Academy of Sciences; and Peter Jacobs, of George Mason University.An image of Hurricane Harvey taken by the GOES-16 satellite as the storm collided with the Texas coast. (Image courtesy NASA.) Matching evaporation and rainAs hurricanes move over the ocean, their strong winds strafe the sea surface, making it easier for water to evaporate. The process of evaporation also requires energy from heat, and the warmer the temperatures are in the upper ocean and at the ocean surface, the more energy is available.As the storm progresses over the ocean, evaporating water as it goes, it leaves a cold wake in its path. In the case of Hurricane Harvey, the scientists found the cold wake was not very cold. So much heat was available in the upper layer of the ocean that, as the surface temperature was cooled from the storm, heat from below welled up, rewarming the surface waters and continuing to feed the storm.The near-surface ocean temperature before the storm's passage was upward of 30 degrees Celsius (86 degrees Fahrenheit), and after passage the temperature was still around 28.5 C (83 F). Sea surface temperatures above 26 C (79 F) are typically needed for a hurricane to continue to grow.Even after Harvey made landfall, its arms reached out over the ocean, continuing to draw strength (and water) from the still-warm Gulf."The implication is that the warmer oceans increased the risk of greater hurricane intensity and duration," Trenberth said. "While we often think of hurricanes as atmospheric phenomena, it's clear that the oceans play a critical role and will shape future storms as the climate changes."The scientists were able to measure the total loss in ocean heat, mostly due to evaporation, as the storm moved over the Gulf. They also measured the latent heat released over land as the water vapor turned back into liquid water and fell as rain. They then compared those two measurements and found that they corresponded.The study highlights the increased threat of future supercharged hurricanes due to climate change, Trenberth said."We know this threat exists, and yet in many cases, society is not adequately planning for these storms," Trenberth said. "I believe there is a need to increase resilience with better building codes, flood protection, and water management, and we need to prepare for contingencies, including planning evacuation routes and how to deal with power cuts."About the studyTitle: Hurricane Harvey Links to Ocean Heat Content and Climate Change AdaptationAuthors: Kevin E. Trenberth, Lijing Cheng, Peter Jacobs, Yongxin Zhang, and John FasulloJournal: Earth's Future. DOI: 10.1029/2018EF000825Writer:Laura Snider, Senior Science Writer

A+ long-term credit rating continues for UCAR

BOULDER, Colo. — The credit rating agency Standard & Poor's Global Ratings (S&P) has affirmed an A+ long-term bond rating for the University Corporation for Atmospheric Research (UCAR).In its report, S&P stated that the strong rating is a reflection of UCAR's important role as a leading organization supporting the academic community that studies atmospheric and Earth system science. The report also cites the organization's history of successful operations and growing financial resources."The stable outlook reflects our anticipation that during the two-year outlook period, UCAR's operations will maintain balanced operations and financial resources will remain stable or improve," stated the report.Since the last S&P rating announcement in 2016, UCAR's membership base has grown to include 117 North American colleges and universities focused on research and training in the atmospheric and related Earth system sciences, as well as 56 international affiliates. UCAR manages the National Center for Atmospheric Research (NCAR) with sponsorship by the National Science Foundation. UCAR's annual expenditure in fiscal year 2017 was about $247 million."The continued A+ rating is a reflection of UCAR's stability and its focus on sound fiscal principles," said Susan Avery, chair of the UCAR Board of Trustees. "This high rating is also a testament to the hard work the staff at UCAR performs on a daily basis to be the best possible stewards of the NSF investment in NCAR."

U.S. gains in air quality are slowing down

BOULDER, Colo. — After decades of progress in cleaning up air quality, U.S. improvements for two key air pollutants have slowed significantly in recent years, new research concludes. The unexpected finding indicates that it may be more difficult than previously realized for the nation to achieve its goal of decreased ozone pollution, scientists said."Although our air is healthier than it used to be in the 80s and 90s, air quality in the U.S. is not progressing as quickly as we thought," said National Center for Atmospheric Research (NCAR) scientist Helen Worden, a co-author. "The gains are starting to slow down."The study, by an international team of researchers, analyzed extensive satellite and ground-based measurements of nitrogen oxides and carbon monoxide. They found that levels of pollutants that can contribute to the formation of ground-level ozone, or smog, have failed to continue a fairly steady decline as estimated by the U.S. Environmental Protection Agency."We were surprised by the discrepancy between the estimates of emissions and the actual measurements of pollutants in the atmosphere," added Zhe Jiang, the lead author of the study. "These results show that meeting future air quality standards for ozone pollution will be more challenging than previously thought."Jiang, who conducted much of the research during a postdoctoral fellowship at NCAR, is now with the University of Science and Technology of China.The study will be published next week in the Proceedings of the National Academy of Sciences. The research was funded primarily by NASA, the National Oceanic and Atmospheric Administration, the University of Colorado Boulder, and the National Science Foundation, which sponsors NCAR.Slowdown in air quality improvement. Estimates by the Environmental Protection Agency indicate that levels of nitrogen oxides have continued their decline over the past decade. But top-down emission estimates using satellite measurements show that the decline has slowed dramatically in recent years. (Figure by Zhe Jiang, redrawn by Simmi Sinha, UCAR.)Revealing the slowdownNitrogen oxides and carbon monoxide contribute to the formation of ground-level ozone, a pollutant that is harmful to human health and the environment. Levels of the pollutants have declined significantly since passage of the 1970 Clean Air Act, which spurred development of emission-reducing technologies, such as catalytic converters on automobiles and low nitrogen oxide burners at power plants.A number of cities and outlying areas in the United States, however, remain out of compliance with EPA standards for ozone, which the agency made more stringent in 2015.EPA emission estimates are based on monitored readings or engineering calculations of pollutants emitted by vehicles, factories, or other sources.To obtain a fuller picture of national pollution levels, Jiang and his co-authors turned to satellite instruments that measure levels of nitrogen oxides and carbon monoxide. They analyzed these atmospheric observations with advanced computer simulations and statistical analyses, both to quantify pollutant concentrations and to map their concentrations across the contiguous United States. They then corroborated their findings with observations from air quality monitoring stations that measure local pollution levels.The results showed that emission reductions slowed down dramatically in the five-year period from 2011 to 2015 compared to 2005 to 2009. Whereas nitrogen oxide concentrations dropped by 7 percent yearly from 2005 to 2009, they declined by just 1.7 percent yearly from 2011 to 2015—a 76 percent slowdown. Those findings contrast with EPA emission inventories, which put the slowdown at only 16 percent during the same time period.Similarly, the study showed that carbon monoxide levels have declined much more slowly in recent years.The research team originally thought that emissions from Asia could be playing a role, but this was not supported by the data. The measurements showed that the slowdown in improved air pollution levels was particularly pronounced in the eastern United States, one of several signs that the pollutants were not coming in from overseas.The authors concluded that some of the reasons for the discrepancy for nitrogen oxides may be:the decreasing relative contributions of gasoline cars to the pollutant, due to the ongoing effectiveness of three-way catalytic converters;the increasing relative emissions of nitrogen oxides from such sources as industrial, residential, and commercial boilers and off-road vehicles; andslower-than-expected reductions in emissions by heavy-duty diesel trucks that have newer (and still maturing) catalytic converter technologies.The study concluded that the slowdown in carbon monoxide, which is largely emitted by cars, is likely due to the large gains that have already been achieved by equipping cars with three-way catalytic converters."As you become effective at controlling emissions from cars and power plants, the other sources become more important and there's less information about them," said co-author Brian McDonald, a scientist with the National Oceanic and Atmospheric Administration and the Cooperative Institute for Research in Environmental Sciences.The authors said that follow-up research, combining EPA inventories with a new generation of increasingly sophisticated satellite instruments, would lead to a more detailed understanding about how pollution is changing in response to emission controls."The top-down satellite measurements and the inventories provide complementary data that will enable us to get better estimates of the emission sources," McDonald said. "It will be useful to learn more about why the discrepancies exist and why the trend toward better air quality is slowing down."About the studyTitle: Unexpected slowdown of US pollutant emission reduction in the last decadeAuthors: Zhe Jiang, Brian C. McDonald, Helen Worden, John R. Worden, Kazuyuki Miyazaki, Zhen Qu, Daven K. Henze, Dylan B. A. Jones, Avelino F. Arellano, Emily V. Fischer, Liye Zhu, and K. Folkert BoersmaPublication: Proceedings of the National Academy of SciencesChanges in Nitrogen Dioxide (NO2) levels. These satellite observations show the changes in NO2 during two recent periods. From 2005 to 2009, NO2 levels declined sharply across much of the United States, as shown in the areas of darkest blue. But in more recent years, NO2 has declined more slowly and even increased slightly in some areas (light red).  The total column NO2 observations (1 unit = 1000 trillion molecules per square centimeter) are from the Ozone Monitoring Instrument (OMI) on NASA's Aura satellite. (Figure by Zhe Jiang, redrawn by Simmi Sinha, UCAR.)

UCAR Congressional Briefing: Subseasonal to seasonal forecasts

WASHINGTON — Federal investments in atmospheric and oceanic research are ushering in major advances in longer-term weather prediction, enabling private companies to provide their clients with valuable forecasts of weather patterns weeks to months in advance, experts said today at a congressional briefing.A panel of scientists representing universities and the private sector agreed that continued government investment in advanced computer modeling, observing tools, and supercomputers is critical for progress in forecasting on longer time scales.The nonprofit University Corporation for Atmospheric Research (UCAR) sponsored the briefing.Subseasonal to seasonal forecasts are predictions of regional weather patterns from two weeks to two years in advance, such as the likelihood of unusually dry or stormy conditions. Improving such forecasts is a national priority, emphasized in the Weather Research and Forecasting Innovation Act that Congress passed last year The panelists said the key to long-term forecasts is increased understanding of the role of the oceans and ocean-atmosphere patterns such as El Niño."Ocean conditions change more slowly than the atmosphere, and that longer memory allows us to predict weather patterns on longer time scales," said Ben Kirtman, a professor of atmospheric sciences at the University of Miami Rosenstiel School of Marine and Atmospheric Science. "How temperatures evolve below the ocean surface, and how the atmosphere and the ocean exchange heat and moisture and momentum — these processes are particularly important when you want to make subseasonal to seasonal forecasts."Gokhan Danabasoglu, chief scientist of the Community Earth System Model at the National Center for Atmospheric Research, said advanced computer models that incorporate observations of ocean conditions are being increasingly used for longer-term prediction. For example, forecasters are able to produce increasingly accurate month-ahead outlooks of temperatures over North America, and researchers have even been able to generate a 10-year forecast of Arctic sea ice conditions, which is important to shipping companies."Better models and more detailed information about ocean conditions lead to better predictions," Danabasoglu said. "We are seeing promising results in longer-term predictions that can be highly beneficial to society."Such forecasts are providing critical intelligence to the $100 billion livestock industry, said Chad McNutt, principal and co-founder of Livestock Wx, which provides livestock producers with advanced weather and climate information. He explained that cattle producers need advance information about temperature and precipitation patterns that affect winter wheat and other crops that cattle graze on. His clients also want to know the timing of insect infestations that affect cattle health."Agriculture sectors like the cattle industry need sustained support for research into improved subseasonal to seasonal forecasting," McNutt said. "The forecasts have real economic implications for producers."Alicia Karspeck, climate scientist and associate director of research partnerships with Jupiter Technology Systems, Inc., said private companies need high-quality, accessible, and continuous data from federal agencies to create long-term prediction products. Jupiter relies on federally funded observations and computer modeling to provide its clients with customized climate and weather risk analytics on timescales of weeks to decades."Federal funding for climate research, observations, and computing creates real value for the private sector, helping us deliver high-quality forecast products to our customers," Karspeck said. "Our company understands that the pipeline from scientific discovery to useful and marketable products relies on a vibrant, well-resourced research sector."Antonio Busalacchi, president of UCAR, emphasized the close partnerships among government agencies, universities, and private companies as they work to improve long-range forecasts."These collaborations are enabling us to better understand the entire Earth system in ways that will allow society to prepare for weather patterns weeks to months in advance," Busalacchi said. "Accurate subseasonal to seasonal forecasts will help to safeguard lives and property as well as benefit every economic sector."The briefing was the latest in a series of UCAR Congressional Briefings that draw on expertise from UCAR's university consortium and public-private partnerships to provide insights into critical topics in the Earth system sciences. Past briefings have focused on moving advances in Earth science research to industry, predicting wildfires, forecasting space weather, tools that improve aviation weather safety, the state of the Arctic, hurricane prediction, potential impacts of El Niño, and new advances in water resources forecasting.

Past tornado experience shapes perception of risk

The following is a news release from the Society of Risk Analysis about a study led by NCAR scientist Julie Demuth.With much of the central plains and Midwest now entering peak tornado season, the impact of these potentially devastating weather events will be shaped in large part by how individuals think about and prepare for them. A new study published in Risk Analysis: An International Journal shows that people's past experiences with tornadoes inform how they approach this type of extreme weather in the future, including their perception of the risk.Led by Julie Demuth, a scientist from the National Center for Atmospheric Research, the study, "Explicating experience: Development of a valid scale of past hazard experience for tornadoes," characterized and measured people's past tornado experiences to determine their impact on the perceived risks of future tornadoes. Better understanding of these factors can help mitigate future societal harm, for instance, by improving risk communication campaigns that encourage preparation for hazardous weather events.The results indicate that people's risk perceptions are highly influenced by a memorable past tornado experience that contributes to unwelcome thoughts, feelings and disruption, which ultimately increase one's fear, dread, worry and depression. Also, the more experiences people have with tornadoes, and the more personalized those experiences, the more likely they are to believe their homes (versus the larger geographic area of their city/town) will be damaged by a tornado within the next 10 years.A tornado in Oklahoma. People's past experiences with tornadoes shapes how they perceive risk when new storms threaten. (Image courtesy NOAA.)In the context of this study, Demuth defines 'past tornado experience' as "the perceptions one acquires about the conditions associated with or impacts of a prior tornado event. Such perceptions are gained by the occurrence of a tornado threat and/or event; directly by oneself or indirectly through others; and at different points throughout the duration of the threat and event."The study was conducted through two surveys distributed to a random sample of residents in tornado prone areas of the U.S. during the spring and fall of 2014. The first survey evaluated an initial set of items measuring experiences, and the second was used to re-evaluate the experience items and to measure tornado risk perceptions. The sample sizes for the two surveys were 144 and 184, respectively.Since tornado experiences can occur at any time throughout one's life, and in multiplicity, the survey items measured both one's most memorable tornado experience and his or her multiple experiences. A factor analysis of the survey items yielded four factors which make up the memorable experience dimensions. Risk awareness: information pertaining to the possibility of a specific tornado hazard occurring, as well as threat-related social cues from both people and the media.Risk personalization: one's protective behavioral and emotional responses as well as visual, auditory and tactile sensations experienced during the tornado.Personal intrusive impacts: ways that one is personally affected by an experience, including intangible, unpleasant thoughts and feelings from the experience.Vicarious troubling impacts: others' tangible impacts and verbal accounts of their experiences and intangible intrusive impacts. The "others" are people known personally by the responding individual. Although all the items in this factor reflect others' accounts of a tornado experience, the respondent experiences these aspects by hearing about or witnessing them.The factor analysis revealed two factors contributing to the multiple experience dimensions: common threat and impact communication, and negative emotional responses. The first factor captures one's personal experience with receiving common types of information (e.g., sirens) about tornado threats and tornado-related news. The second factor captures the amount of experience a respondent has with fearing for their own life, a loved one's life and worrying about their property due to a tornado.Individual's past tornado experiences are multi-faceted and nuanced with each of the above six dimensions exerting a different influence on tornado risk perceptions. These dimensions have not been previously analyzed, particularly the intangible aspects - feelings, thoughts and emotions."This research can help meteorologists who provide many essential, skillful risk messages in the form of forecasts, watches, and warnings when tornadoes (and other hazardous weather) threaten. This research can help meteorologists recognize the many ways that people's past tornado experiences shape what they think and do, in addition to the weather forecasts they receive," states Demuth.The Society for Risk Analysis is a multidisciplinary, interdisciplinary, scholarly, international society that provides an open forum for all those interested in risk analysis. SRA was established in 1980 and has published Risk Analysis: An International Journal, the leading scholarly journal in the field, continuously since 1981. For more information, visit

Lory Mitchell Wingate joins UCAR leadership

BOULDER, Colo. — The University Corporation for Atmospheric Research (UCAR) has named Lory Mitchell Wingate as its new senior vice president and chief operating officer. She will assume her new responsibilities on May 21.Wingate, who succeeds Michael Farrar, will ensure that UCAR continues to deliver the highest quality and most cost-effective services to the National Center for Atmospheric Research (NCAR). She will help further solidify UCAR’s essential role in supporting research, innovation, education, and diversity. UCAR manages NCAR on behalf of the National Science Foundation. "This position is critical for executing UCAR's primary mission, which is to be an exemplary steward of the National Science Foundation's investment in NCAR," said UCAR President Antonio J. Busalacchi. "Lory's extensive management experience and her innovative accomplishments at for-profit and nonprofit research organizations will be a great asset to our organization and the Earth system science community. I look forward to working with her as UCAR extends its record of managerial excellence."Wingate comes to UCAR from the National Radio Astronomy Observatory, where she has implemented and led the Program Management Department. She oversees all aspects of program management, project management, and systems engineering at the observatory.She previously served as program integrator of the Joint Strike Fighter International Program at Lockheed Martin Aeronautics. There, she led a global team, including nine partner nations and two major partner organizations, implementing solutions for engineering, manufacturing, and support for what became a 10,000-employee workforce. Prior to that, she worked as operations manager and research assistant for The RAND Corporation, ensuring that all proposals, project plans, and budgets were developed and implemented.Wingate has an MBA in information systems from California Lutheran University and holds certifications in project management and systems engineering. She has significant teaching experience at the graduate and undergraduate levels.

University of Alabama joins UCAR consortium

UCAR is welcoming seven new member universities, bringing the total membership for the nonprofit consortium to 117 universities and colleges across North America. The following is a news release from the University of Alabama published today after the membership agreement was officially signed. The other new members are Duke University; Louisiana State University; University of Maryland, Baltimore County; University of Massachusetts, Amherst; University of Massachusetts, Lowell; and University of Saskatchewan.TUSCALOOSA, Ala. — The University of Alabama’s partnership with the University Corporation for Atmospheric Research will benefit students, the state and the nation, said UA President Stuart R. Bell at an on-campus ceremony today.Bell signed an agreement alongside UCAR President Antonio J. Busalacchi declaring UA as a member of the national organization focused on research and training in the atmospheric and related Earth system sciences.“UA’s partnership with UCAR provides new opportunities for additional research into the atmospheric and related Earth system sciences, which is so vital for improving forecasts, protecting life and property, and fostering economic growth,” Bell said.UCAR President Antonio J. Busalacchi (left) shakes hands with University of Alabama President Stuart R. Bell at the official signing ceremony making UA a UCAR member. Photo courtesy Bill Kuo, UCAR. UCAR is a consortium of 117 universities and colleges across North America and manages the National Center for Atmospheric Research under sponsorship by the National Science Foundation. Through its community programs, UCAR supports and extends the capabilities of its academic consortium.UA was voted into UCAR at its annual meeting in October, along with six other institutions including Duke University and Louisiana State University.“We are honored to have The University of Alabama join the UCAR community,” Busalacchi said. “We look forward to collaborating with the University and their strong academic programs to advance our knowledge of weather, water, climate and other vital aspects of the Earth system for the benefit of Alabama residents and all of society.”UCAR has a broad community of researchers and world-class assets, including research aircraft, powerful supercomputing and innovative models, that will assist UA in further developing educational and research programs in the atmospheric sciences.“The community models developed by NCAR and its university partners help keep Alabama citizens safe from hurricanes, tornados, and other dangerous weather events, and UA researchers will be engaged in building the next generation of models,” Bell said. “The Earth sciences research that we are conducting with NCAR and UCAR’s member universities is vital for protecting lives and property, providing a major return on the investment by taxpayers.”The University has ongoing research in the areas of climatology, atmospheric hazards, geocomputation, geomorphology, remote sensing and silviculture as well as hydroclimate and landscape modeling. Projects in these areas have received support from the National Oceanic and Atmospheric Administration, NASA, the National Science Foundation, the United States Army Corps of Engineers and the U.S. Geological Survey.

Reconciling Paris Agreement goals for temperature, emissions

As society faces the challenge of limiting warming to no more than 2 degrees Celsius, new research finds an apparent contradiction: Achieving that goal doesn't necessarily require cutting greenhouse gas emissions to zero, as called for in the Paris Agreement. But under certain conditions, even zero emissions might not be enough.The Paris Agreement, a global effort to respond to the threats of human-caused climate change, stipulates that warming be limited to between 1.5 degrees C (2.7 degrees Fahrenheit) and 2 degrees C (3.6 degrees F). It also stipulates that countries achieve net-zero greenhouse gas emissions in the second half of this century. But the relationship between the two — is the emissions goal sufficient or even necessary to meet the temperature goal? — has not been well understood.In a new study published in the journal Nature Climate Change, scientists used a computer model to analyze a variety of possible future scenarios to better understand how emissions reductions and temperature targets are connected. The study, published March 26, was led by Katsumasa Tanaka at the National Institute for Environmental Studies in Japan and co-authored by Brian O'Neill at the U.S. National Center for Atmospheric Research."What we found is that the two goals do not always go hand in hand," Tanaka said. "If we meet temperature targets without first overshooting them, we don't have to reduce greenhouse gas emissions to zero. But if we do reduce emissions to zero, we still might not meet the temperature targets if we don't reduce emissions quickly enough."The team also found that whether temperatures overshoot the target temporarily has a critical impact on the scale of emissions reductions needed."If we overshoot the temperature target, we do have to reduce emissions to zero. But that won’t be enough," Tanaka said. "We'll have to go further and make emissions significantly negative to bring temperatures back down to the target by the end of the century."The research was supported by the Environment Research and Technology Development Fund (2-1702) of the Environmental Restoration and Conservation Agency in Japan and by the U.S. National Science Foundation, NCAR's sponsor.Drafted in 2015, the Paris Agreement has been ratified by more than 170 countries. President Donald Trump announced last year the intention to withdraw the United States from the agreement.Modeling the problem from both sidesFor the study, the researchers used a simplified integrated assessment model that takes into account the physical connections between greenhouse gases and global mean temperature in the climate as well as the economic costs of emissions reductions."We investigated the consistency between the Paris targets in two ways. First we asked, what happens if you just meet the temperature target in a least-cost way? What would emissions look like?" said O'Neill, an NCAR senior scientist. "Then we said, let's just meet the emissions goal and see what kind of temperatures you get."The team generated 10 different scenarios. They found that Earth's warming could be stabilized at 1.5 or 2 degrees C — without overshooting the goal — by drastically cutting emissions in the short term. For example, total greenhouse gas emissions would need to be slashed by about 80 percent by 2033 to hit the 1.5-degree target or by about two-thirds by 2060 to meet the 2-degree target. In both these cases, emissions could then flatten out without ever falling to zero.Due to the difficulty of making such steep cuts, the scientists also looked at scenarios in which the temperature was allowed to temporarily overshoot the targets, returning to 1.5 or 2 degrees by the end of the century. In the 1.5-degree overshoot scenario, emissions fall to zero by 2070 and then stay negative for the rest of the century. (Negative emissions require activities that draw down carbon dioxide from the atmosphere.) For the 2-degree temporary overshoot scenario, emissions fall to zero in 2085 and also become negative, but for a shorter period of time.On the flip side, the scientists also looked at scenarios where they set the emissions levels instead of the temperature. In those cases, they analyzed what would happen if emissions were reduced to zero around mid-century (2060) or at the end of the century (2100). In the first case, the global temperature peaked around the 2-degree target and then declined. But in the second case, the temperature rose above 2 degrees around 2043 and stayed there for a century or more."The timing of when emissions are reduced really matters," O'Neill said. "We could meet the goal set out in the Paris Agreement of reducing emissions to zero in the second half of the century and still wildly miss the temperature targets in the same agreement if we wait to take action."The new study is part of a growing body of research that seeks to better understand and define what it will take to comply with the Paris Agreement. For example, another recent study — led by Tom Wigley, a climate scientist at the University of Adelaide who holds an honorary appointment at NCAR — also looks at the quantity and timing of emissions cuts needed to stabilize global temperature rise at 1.5 or 2 degrees above preindustrial levels. This work focuses in particular on implications for emissions of carbon dioxide, the main component of the broader greenhouse gas emissions category that makes up the Paris emissions target.O'Neill and Tanaka believe their work might be useful as countries begin to report the progress they've made reducing their emissions and adjust their goals. These periods of reporting and readjusting, known as global stocktakes, are formalized as part of the Paris Agreement and occur every five years."Our study and others may help provide countries with a clearer understanding of what work needs to be done to meet the goals laid out in the agreement. We believe that the Paris Agreement needs this level of scientific interpretation," Tanaka said.


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