Search

Your search keyword '"Kharin, V."' showing total 230 results
Start Over Author "Kharin, V." Search Limiters Peer Reviewed
230 results on '"Kharin, V."'

2. Climatological Adaptive Bias Correction of Climate Models.

Author

Scinocca, J. F. and Kharin, V. V.

Subjects
*ATMOSPHERIC models, *EARTH (Planet), *FORECASTING
Abstract

All Earth System Models (ESMs) have climatological biases relative to the observed historical climate. The quality of a model and, more importantly, the accuracy of its predictions are often associated with the magnitude and properties of its biases. For more than a decade, new strategies have been developed to empirically reduce such biases in the model components of ESMs during their execution. The present study considers a cyclostationary class of empirical runtime bias corrections to a climate model, referred to here as empirical runtime bias corrections (ERBCs). Such ERBCs are state independent and designed to reduce biases in the climatological annual cycle of the model. We present a new procedure for deriving such ERBCs called Climatological Adaptive Bias Correction (CABCOR). CABCOR is argued to be superior to the standard relaxation approach to defining ERBCs because it requires only a climatological, rather than a multi‐year time evolving, observational reference data set. As part of this study, we perform a novel analysis of the relaxation approach in which a mapping is made between the parameter values that define the relaxation and the biases produced by ERBCs in the corrected model. This allows us to identify the optimal bias correction produced by the relaxation approach and to additionally demonstrate that the CABCOR approach can produce bias‐corrected models with smaller climatological biases. Plain Language Summary: All climate models have basic‐state biases which are believed to impact their ability to make accurate predictions. We present a new method to derive fixed, repeated annual cycle, correction terms that can be added to a climate model as it runs to reduce its biases. The new method requires less observational information than existing methods and is shown to result in larger bias reductions. Key Points: A new approach to derive empirical runtime bias corrections of a climate model is presentedThe new approach requires only climatological rather than time evolving observed reference statesThe approach is shown to produce larger bias reductions in an atmospheric climate model than existing relaxation‐based methods [ABSTRACT FROM AUTHOR]

Published
2024
Full Text
View/download PDF

4. North Atlantic climate far more predictable than models imply

Author

Smith, D. M., Scaife, A. A., Eade, R., Athanasiadis, P., Bellucci, A., Bethke, I., Bilbao, R., Borchert, L. F., Caron, L.-P., Counillon, F., Danabasoglu, G., Delworth, T., Doblas-Reyes, F. J., Dunstone, N. J., Estella-Perez, V., Flavoni, S., Hermanson, L., Keenlyside, N., Kharin, V., Kimoto, M., Merryfield, W. J., Mignot, J., Mochizuki, T., Modali, K., Monerie, P.-A., Müller, W. A., Nicolí, D., Ortega, P., Pankatz, K., Pohlmann, H., Robson, J., Ruggieri, P., Sospedra-Alfonso, R., Swingedouw, D., Wang, Y., Wild, S., Yeager, S., Yang, X., and Zhang, L.

Published
2020
Full Text
View/download PDF

8. Robust skill of decadal climate predictions

Author

Smith, D. M., Eade, R., Scaife, A. A., Caron, L.-P., Danabasoglu, G., DelSole, T. M., Delworth, T., Doblas-Reyes, F. J., Dunstone, N. J., Hermanson, L., Kharin, V., Kimoto, M., Merryfield, W. J., Mochizuki, T., Müller, W. A., Pohlmann, H., Yeager, S., and Yang, X.

Published
2019
Full Text
View/download PDF

15. Weak Hydrological Sensitivity to Temperature Change over Land, Independent of Climate Forcing

Author

Samset, B. H, Myhre, G, Forster, P. M, Hodnebrog, O, Andrews, T, Boucher, O, Faluvegi, G, Flaeschner, D, Kasoar, M, Kharin, V, Kirkevag, A, Lamarque, J.-F, Olivie, D, Richardson, T. B, Shindell, D, Takemura, T, and Voulgarakis, A

Subjects
Meteorology And Climatology
Abstract

We present the global and regional hydrological sensitivity (HS) to surface temperature changes, for perturbations to CO2, CH4, sulfate and black carbon concentrations, and solar irradiance. Based on results from ten climate models, we show how modeled global mean precipitation increases by 2-3% per kelvin of global mean surface warming, independent of driver, when the effects of rapid adjustments are removed. Previously reported differences in response between drivers are therefore mainly ascribable to rapid atmospheric adjustment processes. All models show a sharp contrast in behavior over land and over ocean, with a strong surface temperature-driven (slow) ocean HS of 3-5%/K, while the slow land HS is only 0-2%/K. Separating the response into convective and large-scale cloud processes, we find larger inter-model differences, in particular over land regions. Large-scale precipitation changes are most relevant at high latitudes, while the equatorial HS is dominated by convective precipitation changes. Black carbon stands out as the driver with the largest inter-model slow HS variability, and also the strongest contrast between a weak land and strong sea response. We identify a particular need for model investigations and observational constraints on convective precipitation in the Arctic, and large-scale precipitation around the Equator.

Published
2018
Full Text
View/download PDF

24. Fast and Slow Precipitation Responses to Individual Climate Forcers: A PDRMIP Multimodel Study

Author

Samset, B. H, Myhre, G, Forster, P.M, Hodnebrog, O, Andrews, T, Faluvegi, G, Flaschner, D, Kasoar, M, Kharin, V, Kirkevag, A, Shindell, D, and Voulgarakis, A

Subjects
Meteorology And Climatology
Abstract

Precipitation is expected to respond differently to various drivers of anthropogenic climate change. We present the first results from the Precipitation Driver and Response Model Intercomparison Project (PDRMIP), where nine global climate models have perturbed CO2, CH4, black carbon, sulfate, and solar insolation. We divide the resulting changes to global mean and regional precipitation into fast responses that scale with changes in atmospheric absorption and slow responses scaling with surface temperature change. While the overall features are broadly similar between models, we find significant regional intermodel variability, especially over land. Black carbon stands out as a component that may cause significant model diversity in predicted precipitation change. Processes linked to atmospheric absorption are less consistently modeled than those linked to top-of-atmosphere radiative forcing. We identify a number of land regions where the model ensemble consistently predicts that fast precipitation responses to climate perturbations dominate over the slow, temperature-driven responses.

Published
2016
Full Text
View/download PDF

29. A verification framework for interannual-to-decadal predictions experiments

Author

Goddard, L., Kumar, A., Solomon, A., Smith, D., Boer, G., Gonzalez, P., Kharin, V., Merryfield, W., Deser, C., Mason, S. J., Kirtman, B. P., Msadek, R., Sutton, R., Hawkins, E., Fricker, T., Hegerl, G., Ferro, C. A. T., Stephenson, D. B., Meehl, G. A., Stockdale, T., Burgman, R., Greene, A. M., Kushnir, Y., Newman, M., Carton, J., Fukumori, I., and Delworth, T.

Published
2013
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results