Program Description

A set of common and challenging problems that we define as the Weather-Climate Interface (WCI) have hindered both weather prediction and climate projections, and where the skills and interests of both communities are essential to their solution. The overarching goal of WCI activities is to enhance dialogue and forge alliances among investigators motivated by weather prediction and climate system research toward the benefit of both applications.

The Common Ground

Much of the public and policy concern with global change is how the intensity, frequency and location of high-impact weather events might evolve under the various global change scenarios. This concern is driven in large part by our current need to mitigate weather and climate disasters in both developed and developing nations and to improve decision making for agriculture, transportation, water management and other key sectors of the economy. Improving the simulation of these high impact events in weather and climate modeling is a key component of the response to these urgent needs of society.

The International and National Opportunities

Bridging the climate-weather interface is well suited to the NCAR role as an integrator and the ESSL goal of prediction across scales.  World Weather Research Program (WWRP) THORPEX and the World Climate Research Program (WCRP) have initiated planning for collaboration in this area.   A major strength of the ESSL Climate and Mesoscale divisions, this international impetus should be met by a strong response from NCAR, presenting an opportunity for international leadership at the forefront of weather-climate research.  The research opportunities abound for major collaborations within the academic community, and centers for climate modeling and operational weather prediction.

Researchers from NCAR and the U.S. academic community held an exploratory workshop organized by TIIMES during the summer of 2006.  They identified the need for increased understanding and improved prediction of tropical convection and the two-way interaction with the large-scales as a scientifically challenging problem well suited to the NSF research community.  Research at the Weather Climate Interface (WCI) will improve the predictive skill.  Fundamental questions include:

• What physical and dynamical processes limit our skill in predicting organized, coherent convection in the tropics and the extent to which predictions can be improved?
• Can we improve the treatment of tropical convection in numerical models, given that in the 40 years since inception of numerical weather prediction, the parameterization of convection and moist processes remains vexingly primitive, and skillful prediction remains correspondingly elusive?
• Will improvements in the representation of tropical convection correct biases in climate system models; lead to dramatic improvements in week two predictions of mid-latitude weather; and improve the skill of projected changes in the tropics under various climate change scenarios?
• To what extent are global prediction/projection improvements dependent upon the success of coupled atmosphere-ocean models to predict the Madden-Julian Oscillation (MJO)?

The NCAR – University Opportunity

The methods for advancement on these topics take advantage of NCAR’s broad strengths, especially in the Climate and Mesoscale divisions of ESSL, Earth Observing Laboratory (EOL) and Computational and Information Systems Laboratory (CISL).  The university community exhibits strengths and interest in predictability studies and model-based diagnostics.  Activities of an NCAR–university effort should include:

• Super parameterization of convection in global models aided by petascale computing resources.
• Nested 3-D high resolution grids within a global WRF model.
• Use of the WRF-based NCAR Regional Climate Model.
• Knowledge of physical relationships derived from theory, cloud resolving models and observations.
• Utilization of data sets from new satellites (e.g., A-TRAIN, CALYPSO, CLOUD-SAT).
• Collaboration with Water Cycle program efforts on the parameterization of continental convection.

Given modest additional resources at NCAR and in the relevant NSF grants programs, substantial progress on all of the above can be made over a period of three to five years.

THORPEX

THe Observing-system Research and
Predictability EXperiment

THORPEX is a long-term research program organized under the World Meteorological Organization's World Weather Research Program. THORPEX research seeks to accelerate improvements in the accuracy of high-impact, 1-14 day weather forecasts for the benefit of society, economy and environmental stewardship. THORPEX seeks to reduce and mitigate the effects of natural disasters on society by transforming timely and accurate weather forecasts into specific and definite information in support of decisions that produce the desired benefits.

THORPEX Reports & Additional Information

International Polar Year (IPY): 2007 - 2008 Proposal for Activities
2006 Retreat Summary: Tropical Convection & the Weather climate Interface | White Paper

For additional information please visit the North American & International THORPEX sites:

International THORPEX

North American THORPEX

THORPEX Program Lead:

Dr. Dave Parsons
Email: DParsons@wmo.int

Mailing Address:
World Meteorological Organization, THOREX
7bis, avenue de la Paix, Case postale 2300, CH-1211 Geneva 2, Switzerland

Program Lead - Contact

Dr. Roy Rasmussen
Email: rasmus@ucar.edu
Phone: 303-497-8430

Dr. Mitch Moncrieff
Email: moncrief@ucar.edu
Phone:303-497-8960

Mailing Address: NCAR, P.O. Box 3000, Boulder, CO USA 80307-3000