Monsoon Responses to Climate Changes—Connecting Past, Present and Future

• Published in: Current climate change reports Vol. 5; no. 2; pp. 63 - 79
• Main Authors: Seth, Anji, Giannini, Alessandra, Rojas, Maisa, Rauscher, Sara A., Bordoni, Simona, Singh, Deepti, Camargo, Suzana J.
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 01-06-2019; Springer Nature B.V
• Subjects: Aerosol effects; Aerosols; Atmospheric Sciences; Carbon dioxide; Climate; Climate Change; Climate Change and Atmospheric Circulation (R Chadwick; Climate Change Management and Policy; Climate models; Climatology; Connecting; Cooling; Earth and Environmental Science; Energy; Environment; Gases; Greenhouse effect; Greenhouse gases; Hierarchies; Monsoons; Oceanography; Paleoclimate; Precipitation; Radiative forcing; Regions; Section Editor; Temperature gradients; Topical Collection on Climate Change and Atmospheric Circulation; Trends; Tropical climate; Tropical climates; Warm climates; Wind; East Asia; Global warming; Paleomonsoons; Climate changes; Monsoons
• ISSN: 2198-6061; 2198-6061
• DOI: 10.1007/s40641-019-00125-y

Purpose of Review
Knowledge of how monsoons will respond to external forcings through the twenty-first century has been confounded by incomplete theories of tropical climate and insufficient representation in climate models. This review highlights recent insights from past warm climates and historical trends that can inform our understanding of monsoon evolution in the context of an emerging energetic framework.
Recent Findings
Projections consistent with paleoclimate evidence and theory indicate expanded/wetter monsoons in Africa and Asia, with continued uncertainty in the Americas. Twentieth century observations are not congruent with expectations of monsoon responses to radiative forcing from greenhouse gases, due to the confounding effect of aerosols. Lines of evidence from warm climate analogues indicate that while monsoons respond in globally coherent and predictable ways to orbital forcing and inter-hemispheric thermal gradients, there are differences in response to these forcings and also between land and ocean.
Summary
Further understanding of monsoon responses to climate change will require refinement of the energetic framework to incorporate zonal asymmetries and the use of model hierarchies.