Recently, two new water vapor line absorption datasets have become available. First, the HITRAN 2000 dataset provides updated information on several water vapor absorption lines in the near infrared. Secondly, an independent study initiated by the European Space Agency (ESA) created a new line dataset for the spectral range between 8592 cm-1 and 20000 cm-1. We provide the necessary coefficients to update the parametrization of near infrared absorption in the ECHAM4 global climate model based on these new data and investigate its impact on the absorption of solar radiation in ECHAM4. We find that compared to the original parameterization, which is based on HITRAN-92, the water vapor absorption is increased by an amount of 0.2 % to 2.0 % depending on absorber mass and the dataset used for calculating the coefficients. The new parametrizations lead to a globally and annually averaged increase in absorption of solar radiation in the GCM of 3.4 W/m2 and 3.8 W/m2, respectively. ¿ 2001 American Geophysical Union |