New Developments and Applications with the NCAR Regional Climate Model (RegCM) (Journal of Geophysical Research, 104, March 1999)
The following set of three related professional papers introduced further developments in an innovative approach for understanding how climate variability and change may influence various resource systems, including future food production in the United States and worldwide. The fundamental issue addressed by the papers concerns the development of high-resolution climate scenarios for use in impacts assessments.
The need for more regional detail in climate scenarios has been pressing for more than a decade.
The methodologies developed by this multidisciplinary team of researchers, led by Linda Mearns, will significantly advance capabilities for constructing such scenarios that assist nations in being better prepared for how to anticipate future weather and climate impacts on world food supplies. This special issue of the Journal of Geophysical Research describes several years of research efforts.
In the overview paper, Giorgi and Mearns discuss outstanding issues in state-of-the-art regional climate modeling (e.g., boundary conditions, model physics, two-way nesting, variable resolution approaches) and introduce the papers in the issue, which range in subject matter from the development of new physics for the model to various applications of the model, including its use for developing high spatial resolution climate scenarios for use in impacts assessments.
These papers illustrate a wide range of applications over the United States, East Asia, Central Asia, and Eastern Africa. (Giorgi., F., and L.O. Mearns, 1999: Introduction to special section: Regional climate modeling revisited. Journal of Geophysical Research, 104(D6), 6335-6352.)
The second paper analyzes the difference in high resolution climate change scenarios formed using two different methods of regionalization: statistical downscaling and regional climate modeling. Boundary conditions from the same general circulation model (GCM), were used
in both methods. The authors found that the two methods generated significantly different
changes in climate when applied to a region of western Nebraska, including opposite directions of change in precipitation. This paper thus further elucidates very important uncertainties in the application of downscaling techniques. [comparison of downscaling methods] (Mearns, L.O., I. Bogardi, F. Giorgi, I. Matyasovszky, and M. Palecki, 1999: Comparison of climate change scenarios generated from regional climate models experiments and statistical downscaling. Journal of Geophysical Research, 104(D6), 6603-6621).
The third paper examines two different types of uncertainty in agricultural impacts assessments: the spatial scale of climate change scenarios, and the choice of crop model type. It is the first paper ever to demonstrate clearly the importance of these uncertainties. The authors
developed a coarse-scale climate change scenario from a GCM used to drive the regional
climate model and a high-resolution scenario generated from control and 2xCO2 results of the
Regional Climate Model (RegCM2) for a region in the central Great Plains. They then applied the two different scenarios to two different crop model types (EPIC and CERES) for both corn and wheat. They found that substantial differences in percentage change in the simulated
yields were calculated based both on the scale of the scenarios and the choice of crop model type. This paper convincingly demonstrates that these uncertainties in climate change impacts
are complex and interactive. [regional climate change scenario] (Mearns, L.O., T. Mavromatis, and E. Tsvetsinskaya, 1999: Comparative responses of EPIC and CERES crop models to high and low spatial resolution climate change scenarios. Journal of Geophysical Research, 104(D6), 6623-6646).
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Creeping Environmental Problems and Sustainable Development in the Aral Sea Basin (Cambridge University Press, 1999)
Multifaceted environmental degradation in the Aral Sea basin has been a touchstone for increasing public awareness of environmental change issues. The Aral crisis has been touted as a "quiet Chernobyl" and is one of the worst human-made environmental catastrophes of the twentieth century. Just a few decades ago, it was the fourth largest inland body of water in the world. Today, it has fallen to sixth place, and it continues to shrink.
This book, edited by Glantz, represents the culmination of five years of research begun in FY95 for the Water Unit of the UN Environment Programme (UNEP), with some initial support from the Water Unit. Twelve key environmental changes in the Aral Sea Basin were identified for assessment in terms of the thresholds of creeping environmental problems associated with them. Each member of a team of twelve Russian, Uzbek, Turkmen, and Kazak experts focused on one of these changes. Each expert had a decade or more of researching a specific environmental problem. Support was provided to them to prepare their chapters. Glantz initiated the development of a theoretical framework in a UNEP/NCAR workshop on Creeping Environmental Problems in 1994. This was organized to identify thresholds of problem awareness, crisis, and policy action for their respective problems. Glantz traveled to Russia several times on trips of opportunity during the FY95-99 period to discuss translation problems and to edit the manuscripts for clarity. The book presents these case studies as lessons to be learned for other areas undergoing creeping environmental change, especially for terminal inland seas. It provides an important multidisciplinary example of how to approach such environmental disasters for students and researchers of environmental studies, global change, political science, and history.
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