Evaluation of regional climate models ALARO-0 and REMO2015 at 0.22° resolution over the CORDEX Central Asia domain

Evaluation of regional climate models ALARO-0 and REMO2015 at 0.22° resolution over the CORDEX Central Asia domain ■

Sara Top, Sara Top, Sara Top, Lola Kotova, Lola Kotova, Lola Kotova, Lesley De Cruz, Lesley De Cruz, Lesley De Cruz, Svetlana Aniskevich, Svetlana Aniskevich, Svetlana Aniskevich, Leonid Bobylev, Leonid Bobylev, Leonid Bobylev, Rozemien De Troch, Rozemien De Troch, Rozemien De Troch, Natalia Gnatiuk, Natalia Gnatiuk, Natalia Gnatiuk, Anne Gobin, Anne Gobin, Anne Gobin, Rafiq Hamdi, Rafiq Hamdi, Rafiq Hamdi, Arne Kriegsmann, Arne Kriegsmann, Arne Kriegsmann, Armelle Reca Remedio, Armelle Reca Remedio, Armelle Reca Remedio, Abdulla Sakalli, Abdulla Sakalli, Abdulla Sakalli, Hans Van de Vyver, Hans Van de Vyver, Hans Van de Vyver, Bert Van Schaeybroeck, Bert Van Schaeybroeck, Bert Van Schaeybroeck, Viesturs Zandersons, Viesturs Zandersons, Viesturs Zandersons, Philippe De Maeyer, Philippe De Maeyer, Philippe De Maeyer, Piet Termonia, Piet Termonia, Piet Termonia, Steven Caluwaerts, Steven Caluwaerts, Steven Caluwaerts

Abstract ■

To allow for climate impact studies on human and natural systems, high-resolution climate information is needed. Over some parts of the world plenty of regional climate simulations have been carried out, while in other regions hardly any high-resolution climate information is available. The CORDEX Central Asia domain is one of these regions, and this article describes the evaluation for two regional climate models (RCMs), REMO and ALARO-0, that were run for the first time at a horizontal resolution of 0.22° (25 km) over this region. The output of the ERA-Interim-driven RCMs is compared with different observational datasets over the 1980-2017 period. REMO scores better for temperature, whereas the ALARO-0 model prevails for precipitation. Studying specific subregions provides deeper insight into the strengths and weaknesses of both RCMs over the CAS-CORDEX domain. For example, ALARO-0 has difficulties in simulating the temperature over the northern part of the domain, particularly when snow cover is present, while REMO poorly simulates the annual cycle of precipitation over the Tibetan Plateau. The evaluation of minimum and maximum temperature demonstrates that both models underestimate the daily temperature range. This study aims to evaluate whether REMO and ALARO-0 provide reliable climate information over the CAS-CORDEX domain for impact modeling and environmental assessment applications. Depending on the evaluated season and variable, it is demonstrated that the produced climate data can be used in several subregions, e.g., temperature and precipitation over western Central Asia in autumn. At the same time, a bias adjustment is required for regions where significant biases have been identified.