Summary
We have studied the regional climate responses in the Middle East and North Africa (MENA) to radiation perturbations caused by the large explosive equatorial volcanic eruptions of the second part of 20th century, El Chichon and Pinatubo, occurred, respectively, in 1982 and 1991. The observations and reanalysis data show that the surface volcanic cooling in the MENA region is two-three times larger than the global mean response to volcanic forcing. The Red Sea surface temperature appears to be also very sensitive to the external radiative impact. E.g., the sea surface cooling, associated with the 1991 Pinatubo eruption, caused deep water mixing and coral bleaching for a few years. To better quantify these effects we use the Geophysical Fluid Dynamics Laboratory global High Resolution Atmospheric Model (HIRAM) to conduct simulations of both the El Chichon and Pinatubo impacts with the effectively 25-km grid spacing. We find that the circulation changes associated with the positive phase of the arctic oscillation amplified the winter temperature anomalies in 1982-1984 and 1991-1993. The dynamic response to volcanic cooling is characterized by the southward shift of the inter-tropical convergence zone in summer and associated impact on the precipitation patterns. These results suggest that the climate regime in the MENA is highly sensitive to external radiative forcing. This is important for better understanding of the climate variability and change in this region.
Biography
Dr. Georgiy Stenchikov has graduated (with distinction) from the Moscow Physical Technical Institute in 1973 and obtained his Ph. D. and habilitation in 1977 and 1989, respectively. Since 2009 he is a Professor in the Division of Physical Sciences and Engineering and in the Division of Mathematics, Computer Science and Engineering, and a Chair of the Earth Sciences and Engineering Program at King Abdullah University of Science and Technology (KAUST) in Saudi Arabia. Dr. Stenchikov began his career in the top Russian numerical modeling research institute, the Computer Center of the USSR Academy of Sciences, where he specialized in numerical methods, radiation gas dynamics, and studied absorption of laser radiation in plasmas for laser fusion applications. In the 1980s, Dr. Stenchikov became interested in climate modeling. From 1986 until 1992, he led a research group in the Computer Center that studied anthropogenic impacts on the Earth’s climate and environmental systems. In 1992, Dr. Stenchikov began working in the United States, first at the University of Maryland and then at Rutgers University. He has conducted interdisciplinary studies in the broad field of climate modeling, atmospheric physics, and environmental sciences and published on the effects of severe thunderstorms on chemical balances in the troposphere and stratosphere-troposphere exchange, aerosol radiative forcing, stretched-grid general circulation modeling, climate downscaling using reagional models, and climate impacts of explosive volcanic eruptions.