Fingerprints of external forcings on Sahel rainfall: aerosols, greenhouse gases, and model-observation discrepancies
Year: 2020
Type: article
Abstract: Over the 20th and 21st centuries, both anthropogenic greenhouse gas increases and changes in anthropogenic aerosols have affected rainfall in the Sahel. Using multiple characteristics of Sahel precipitation, we construct a multivariate fingerprint that allows us to distinguish between the model-predicted responses to greenhouse gases and anthropogenic aerosols. Models project the emergence of a detectable signal of aerosol forcing in the middle of the 20th century and a detectable signal of greenhouse gas forcing at the beginning of the 21st. However, the signals of both aerosol and greenhouse gas forcing in observations emerge earlier and are stronger than in the models, far stronger in the case of aerosols. The similarity between the response to aerosol forcing and the leading mode of internal variability makes it difficult to attribute this model-observation discrepancy to errors in the forcing, errors in the forced response, model inability to capture the amplitude of internal variability, or some combination of these. For greenhouse gases, however, the forced response is distinct from internal variability as estimated by models, and the observations are largely commensurate with the model projections.
Source: Environmental Research Letters
Authors: Kate Marvel, Michela Biasutti, Céline Bonfils
Language: English
Subfield: Global and Planetary Change
Field: Environmental Science
Domain: Physical Sciences
SDG: Climate action
Open Access status: gold
Estimated APC paid: $3,045
Awards: G2917824471, G6020043373, G7943949896, THE SCOPE OF THE RESEARCH CONDUCTED UNDER THIS COOPERATIVE AGREEMENT REQUIRES THE INTEGRATION OF THE NECESSARY EXPERTISE REQUIRED TO TACKLE MULTIDISCIPLINARY MULTIFACETED PROBLEMS INVOLVING THE OBSERVATION AND MODELING OF THE EARTH'S CLIMATE SYSTEM INCLUDING CLIMATE VARIABILITY LONG-TERM CLIMATE CHANGE AND THE IMPACTS OF CLIMATE CHANGE. THE COLLABORATION BETWEEN SCIENTISTS AT THE GODDARD INSTITUTE FOR SPACE STUDIES AND THE CENTER FOR CLIMATE SYSTEMS RESEARCH (GISS/CCSR) FULFILLS THIS SCOPE IN LARGE PART THROUGH THE DEVELOPMENT AND APPLICATION OF COMPLEX COMPUTATIONAL EARTH SYSTEM MODELS. CCSR PERSONNEL EMPLOY OBSERVATIONS AND SIMULATION RESULTS TO ADVANCE THE STUDY OF CLIMATE SENSITIVITY TO BOTH NATURAL AND ANTHROPOGENIC FORCINGS. THEY CONTRIBUTE TO NATIONAL AND INTERNATIONAL ASSESSMENTS PROVIDING AN IMPROVED UNDERSTANDING OF THE PHYSICAL BASIS OF CLIMATE CHANGE AS WELL AS RESEARCH INTO THE AREA OF CLIMATE IMPACTS AS THEY RELATE TO SOCIETAL VULNERABILITIES FUTURE ADAPTATION STRATEGIES AND MITIGATION POTENTIAL. GISS/CCSR WAS ESTABLISHED WITH THE OBJECTIVE OF PROVIDING AN ENHANCED UNDERSTANDING OF THE EARTH'S CLIMATE SENSITIVITY CLIMATE VARIABILITY AS WELL AS THE FORCING AND FEEDBACK MECHANISMS THAT CONTROL THEM. HOWEVER THE CENTER'S OBJECTIVES ALSO INCLUDE RESEARCH ON THE TYPES OF CLIMATE-RELATED CHANGES THAT SOCIETIES WILL FACE DURING THE COMING DECADES TO HELP DETERMINE THE SEVERITY OF THE IMPACTS ACROSS DIVERSE SECTORS SUCH AS AGRICULTURE PUBLIC HEALTH AND TRANSPORTATION INFRASTRUCTURE. IN ADDITION TO BASIC RESEARCH GISS/CCSR SCIENTISTS WORK INTERACTIVELY WITH STAKEHOLDERS TO GENERATE ACTIONABLE INFORMATION THAT WILL HELP THE PUBLIC BECOME MORE AWARE OF CLIMATE-RELATED RISKS BECOME MORE RESILIENT TO THE IMPACTS OF FUTURE CLIMATE-RELATED PROBLEMS AND TO INCREASE THE NATION'S CAPACITY TO SEIZE OPPORTUNITIES THAT COULD BE PRESENTED IF ENVIRONMENTAL CHANGES CAN BE RENDERED MORE PREDICTABLE., G895790057
OpenAlex ID: W3015068214