Research Tools

CCSM and Water Vapor

NCAR experimenters boosted resolution fourfold in two key components of the CCSM to produce the fine-scale details in this animation, which captures one month of a five-year simulation. The animation shows the global circulation pattern that transports water vapor from the tropics toward the poles, an atmospheric feature generally well simulated by models. But by dialing up the resolution, regional weather phenomena also emerge, including fronts and storm systems not previously visible in global models. For example, several tropical depressions form in the western Pacific Ocean, heading toward the east coast of Asia. Starting around August 8, two of these storms spin up into hurricanes (called tropical cyclones or typhoons in the western Pacific). Even the eyes of the hurricanes are visible.

The breakthrough simulation demonstrates the CCSM's ability to reproduce the behavior of these fine-scale features with remarkable fidelity. For the experiment, high-resolution configurations of the atmospheric (CAM) and land-surface components (CLM) of the CCSM were free to evolve over time, while specifications of sea-ice extent and sea-surface temperatures came from observations made in 1997.

Since models are used to explore the statistical properties of the Earth's systems, not day-to-day weather, the simulation illustrated by this animation is not intended to recreate specific events. It's noteworthy, however, that two super typhoons actually formed in the Pacific during August 1997.

Data points for the atmospheric model were about 37 kilometers (23 miles) apart on a three-dimensional grid, compared with a resolution of about 150 km (93 mi) for CCSM simulations prepared for the IPCC Fourth Assessment Report. (Image courtesy Earth and Sun Systems Laboratory, NCAR.)

CCSM3 Animation

The CGD Division (NESL) and the CCSM Community have released an updated CCSM3 animation that models global warming up to the year 2100 in each of the four IPCC Fourth Assessment Report scenarios for CO2 levels. Entitled, "Surface temperature change relative to 1879 - 1899 baseline," the model shows the temporary cooling effects during the 5 major volcanic eruptions of this time period, and then the model's estimates of warming under the different scenarios.