Land surface anomaly simulations and predictions with a climate model: an El Niño Southern Oscillation case study

Abstract

The ability of climate models to reproduce and predict land surface anomalies is an important but little-studied topic. In this study, an atmosphere and ocean assimilation scheme is used to determine whether HadCM3 can reproduce and predict snow water equivalent and soil moisture during the 1997-1998 El Niño Southern Oscillation event. Soil moisture is reproduced more successfully, though both snow and soil moisture show some predictability at 1-and 4-month lead times. This result suggests that land surface anomalies may be reasonably well initialized for climate model predictions and hydrological applications using atmospheric assimilation methods over a period of time.

Decadal climate prediction (project GCEP)

“…The analysed atmospheric and oceanic conditions are then assimilated concurrently directly into the coupled climate model using a very simple nudging technique. The resulting 'climate model analysis', typically over the period 1979-2001, then contains interesting information on other nonassimilated fields such as sea ice cover, snow cover and soil moisture, which can be compared with independent observations (see the companion paper by Putt et al (2009)).…”

“…The analysed atmospheric and oceanic conditions are then assimilated concurrently directly into the coupled climate model using a very simple nudging technique. The resulting 'climate model analysis', typically over the period 1979-2001, then contains interesting information on other nonassimilated fields such as sea ice cover, snow cover and soil moisture, which can be compared with independent observations (see the companion paper by Putt et al (2009) (iii) running this ensemble of experiments forward, e.g. from May 1991, with the free coupled model (no further assimilation) for several years (Smith et al run hindcasts for 10 years), where no future information is used, e.g.…”

The environmental eScience revolution

“…Weather forecast models usually make predictions of the atmosphere only a few days ahead, but we can now run fully coupled models of both atmosphere and ocean that can make predictions with some skill over seasons if we have sufficiently good knowledge of the initial state of the atmosphere and oceans. Both and Putt et al (2009) use a coupled model, HadCM3, to investigate whether such a fully coupled model can be used to make useful seasonal predictions, using an ensemble approach of running the model several times to understand the errors in the initial conditions. look at ocean heat anomalies, and show that some aspects of the model carry predictive skill 2 years ahead, while Putt et al (2009) examine seasonal snow cover in El Niño events and also find that there is predictability into the second year of snow cover.…”

“…Both and Putt et al (2009) use a coupled model, HadCM3, to investigate whether such a fully coupled model can be used to make useful seasonal predictions, using an ensemble approach of running the model several times to understand the errors in the initial conditions. look at ocean heat anomalies, and show that some aspects of the model carry predictive skill 2 years ahead, while Putt et al (2009) examine seasonal snow cover in El Niño events and also find that there is predictability into the second year of snow cover. Haines et al (2009) have written a system that allows the Hadley Centre decadal climate prediction system to be run across a compute grid, so that a far larger ensemble prediction can be made.…”