Articles | Volume 14, issue 5
https://doi.org/10.5194/gmd-14-2691-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/gmd-14-2691-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Model evaluation paper
| 
18 May 2021
Model evaluation paper |
| 18 May 2021
| 18 May 2021
Sensitivity of precipitation and temperature over the Mount Kenya area to physics parameterization options in a high-resolution model simulation performed with WRFV3.8.1
Martina Messmer
CORRESPONDING AUTHOR
Climate and Environmental Physics, University of Bern, Bern, Switzerland
Oeschger Centre for Climate Change Research, University of Bern, Bern, Switzerland
School of Earth Sciences, The University of Melbourne, Melbourne, Victoria, Australia
Santos J. González-Rojí
Climate and Environmental Physics, University of Bern, Bern, Switzerland
Oeschger Centre for Climate Change Research, University of Bern, Bern, Switzerland
Christoph C. Raible
Climate and Environmental Physics, University of Bern, Bern, Switzerland
Oeschger Centre for Climate Change Research, University of Bern, Bern, Switzerland
Thomas F. Stocker
Climate and Environmental Physics, University of Bern, Bern, Switzerland
Oeschger Centre for Climate Change Research, University of Bern, Bern, Switzerland
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Patricio Velasquez, Jed O. Kaplan, Martina Messmer, Patrick Ludwig, and Christoph C. Raible
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Woon Mi Kim and Christoph C. Raible
Clim. Past, 17, 887–911, https://doi.org/10.5194/cp-17-887-2021, https://doi.org/10.5194/cp-17-887-2021, 2021
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Frerk Pöppelmeier, Jeemijn Scheen, Aurich Jeltsch-Thömmes, and Thomas F. Stocker
Clim. Past, 17, 615–632, https://doi.org/10.5194/cp-17-615-2021, https://doi.org/10.5194/cp-17-615-2021, 2021
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The parameter space of the COSMO-CLM RCM is investigated for the Central Asia CORDEX domain using a perturbed physics ensemble (PPE) with different parameter values. Results show that only a subset of model parameters presents relevant changes in model performance and these changes depend on the considered region and variable: objective calibration methods are highly necessary in this case. Additionally, the results suggest the need for calibrating an RCM when targeting different domains.
Jinhwa Shin, Christoph Nehrbass-Ahles, Roberto Grilli, Jai Chowdhry Beeman, Frédéric Parrenin, Grégory Teste, Amaelle Landais, Loïc Schmidely, Lucas Silva, Jochen Schmitt, Bernhard Bereiter, Thomas F. Stocker, Hubertus Fischer, and Jérôme Chappellaz
Clim. Past, 16, 2203–2219, https://doi.org/10.5194/cp-16-2203-2020, https://doi.org/10.5194/cp-16-2203-2020, 2020
Short summary
Short summary
We reconstruct atmospheric CO2 from the EPICA Dome C ice core during Marine Isotope Stage 6 (185–135 ka) to understand carbon mechanisms under the different boundary conditions of the climate system. The amplitude of CO2 is highly determined by the Northern Hemisphere stadial duration. Carbon dioxide maxima show different lags with respect to the corresponding abrupt CH4 jumps, the latter reflecting rapid warming in the Northern Hemisphere.
Jeemijn Scheen and Thomas F. Stocker
Earth Syst. Dynam., 11, 925–951, https://doi.org/10.5194/esd-11-925-2020, https://doi.org/10.5194/esd-11-925-2020, 2020
Short summary
Short summary
Variability of sea surface temperatures (SST) in 1200–2000 CE is quite well-known, but the history of deep ocean temperatures is not. Forcing an ocean model with these SSTs, we simulate temperatures in the ocean interior. The circulation changes alter the amplitude and timing of deep ocean temperature fluctuations below 2 km depth, e.g. delaying the atmospheric signal by ~ 200 years in the deep Atlantic. Thus ocean circulation changes are shown to be as important as SST changes at these depths.
Patricio Velasquez, Martina Messmer, and Christoph C. Raible
Geosci. Model Dev., 13, 5007–5027, https://doi.org/10.5194/gmd-13-5007-2020, https://doi.org/10.5194/gmd-13-5007-2020, 2020
Short summary
Short summary
This work presents a new bias-correction method for precipitation that considers orographic characteristics, which can be used in studies where the latter strongly changes. The three-step correction method consists of a separation into orographic features, correction of low-intensity precipitation, and application of empirical quantile mapping. Seasonal bias induced by the global climate model is fully corrected. Rigorous cross-validations illustrate the method's applicability and robustness.
Cited articles
Angevine, W. M., Bazile, E., Legain, D., and Pino, D.: Land surface spinup for episodic modeling, Atmos. Chem. Phys., 14, 8165–8172, https://doi.org/10.5194/acp-14-8165-2014, 2014. a
Ayugi, B. O., Wen, W., and Chepkemoi, D.: Analysis of Spatial and Temporal
Patterns of Rainfall Variations over Kenya, J. Environ.
Earth Sci., 6, 69–83–83, 2016. a
Ban, N., Schmidli, J., and Schär, C.: Evaluation of the
convection-resolving regional climate modeling approach in decade-long
simulations, J. Geophys. Res.-Atmos., 119, 7889–7907,
https://doi.org/10.1002/2014JD021478, 2014. a
Barry, R. G.: Mountain Weather and Climate, Cambridge University Press, Cambridge, 3rd edn.,
https://doi.org/10.1017/CBO9780511754753, 2008. a
Behera, S. K., Luo, J. J., Masson, S., Rao, S. A., Sakuma, H., and Yamagata,
T.: A CGCM Study on the Interaction between IOD and ENSO, J. Climate,
19, 1688–1705, https://doi.org/10.1175/JCLI3797.1, 2006. a
Bellprat, O., Kotlarski, S., Lüthi, D., De Elía, R., Frigon, A., Laprise, R.,
and Schär, C.: Objective Calibration of Regional Climate Models:
Application over Europe and North America, J. Climate, 29, 819–838,
https://doi.org/10.1175/JCLI-D-15-0302.1, 2016. a
Brune, S., Buschow, S., and Friederichs, P.: Observations and high-resolution
simulations of convective precipitation organization over the tropical
Atlantic, Q. J. Roy. Meteor. Soc., 146,
1545–1563, https://doi.org/10.1002/qj.3751, 2020. a
Camberlin, P. and Philippon, N.: The East African March–May Rainy
Season: Associated Atmospheric Dynamics and Predictability over the
1968–97 Period, J. Climate, 15, 1002–1019,
https://doi.org/10.1175/1520-0442(2002)015<1002:TEAMMR>2.0.CO;2, 2002. a
Collier, E., Mölg, T., and Sauter, T.: Recent Atmospheric Variability at Kibo
Summit, Kilimanjaro, and Its Relation to Climate Mode Activity, J.
Climate, 31, 3875–3891, https://doi.org/10.1175/JCLI-D-17-0551.1, 2018. a
Collins, W. D., Rasch, P. J., Boville, B. A., Hack, J. J., McCaa, J. R., Williamson, D. L., Kiehl, J. T., Briegleb, B., Bitz, C., Lin, S.-J., Zhang, M., and Dai, Y.: Description of the
NCAR community atmosphere model (CAM 3.0), technical note, https://doi.org/10.5065/D63N21CH, 2004. a
Cook, K. H. and Vizy, E. K.: Projected Changes in East African Rainy
Seasons, J. Climate, 26, 5931–5948,
https://doi.org/10.1175/JCLI-D-12-00455.1, 2013. a, b, c
Dudhia, J.: Numerical Study of Convection Observed during the Winter Monsoon
Experiment Using a Mesoscale Two-Dimensional Model, J.
Atmos. Sci., 46, 3077–3107,
https://doi.org/10.1175/1520-0469(1989)046<3077:NSOCOD>2.0.CO;2, 1988. a
Finney, D. L., Marsham, J. H., Jackson, L. S., Kendon, E. J., Rowell, D. P.,
Boorman, P. M., Keane, R. J., Stratton, R. A., and Senior, C. A.:
Implications of Improved Representation of Convection for the East
Africa Water Budget Using a Convection-Permitting Model,
J. Climate, 32, 2109–2129, https://doi.org/10.1175/JCLI-D-18-0387.1, 2019. a
Funk, C., Peterson, P., Landsfeld, M., Pedreros, D., Verdin, J., Shukla, S.,
Husak, G., Rowland, J., Harrison, L., Hoell, A., and Michaelsen, J.: The
climate hazards infrared precipitation with stations – a new environmental
record for monitoring extremes, Sci. Data, 2, 1–21,
https://doi.org/10.1038/sdata.2015.66, 2015. a, b, c, d
Gichuki, F. N., Liniger, H., and Schwilch, G.: Knowledge about highland –
lowland interactions: the role of a natural resource information system,
Eastern and Southern Africa Geographical Journal, 8, 5–14, 1998. a
Giorgi, F., Torma, C., Coppola, E., Ban, N., Schär, C., and Somot, S.:
Enhanced summer convective rainfall at Alpine high elevations in response
to climate warming, Nat. Geosci., 9, 584–589, https://doi.org/10.1038/ngeo2761,
2016. a
Gómez-Navarro, J. J., Raible, C. C., Bozhinova, D., Martius, O., García Valero, J. A., and Montávez, J. P.: A new region-aware bias-correction method for simulated precipitation in areas of complex orography, Geosci. Model Dev., 11, 2231–2247, https://doi.org/10.5194/gmd-11-2231-2018, 2018. a
Grell, G. A. and Freitas, S. R.: A scale and aerosol aware stochastic convective parameterization for weather and air quality modeling, Atmos. Chem. Phys., 14, 5233–5250, https://doi.org/10.5194/acp-14-5233-2014, 2014. a
Gu, H., Jin, J., Wu, Y., Ek, M. B., and Subin, Z. M.: Calibration and
validation of lake surface temperature simulations with the coupled
WRF-lake model, Clim. Change, 129, 471–483,
https://doi.org/10.1007/s10584-013-0978-y, 2015. a, b
Hastenrath, S. and Polzin, D.: Dynamics of the surface wind field over the
equatorial Indian Ocean, Q. J. Roy. Meteor. Soc., 130, 503–517, https://doi.org/10.1256/qj.03.79, 2004. a
Hastenrath, S. and Polzin, D.: Mechanisms of climate anomalies in the
equatorial Indian Ocean, J. Geophys. Res.-Atmos., 110,
https://doi.org/10.1029/2004JD004981, 2005. a
Hastenrath, S., Polzin, D., and Mutai, C.: Circulation Mechanisms of Kenya
Rainfall Anomalies, J. Climate, 24, 404–412,
https://doi.org/10.1175/2010JCLI3599.1, 2010. a
Hong, S.-Y. and Lim, J.-O. J.: The WRF single-moment 6-class microphysics
scheme (WSM6), Asia-Pacific Journal of Atmospheric Sciences, 42, 129–151,
2006. a
Hong, S.-Y., Noh, Y., and Dudhia, J.: A New Vertical Diffusion Package with an
Explicit Treatment of Entrainment Processes, Mon. Weather Rev., 134,
2318–2341, https://doi.org/10.1175/MWR3199.1, 2006. a
Huffman, G.: TRMM (TMPA-RT) Near Real-Time Precipitation L3 3 hour 0.25 degree × 0.25 degree V7, edited by: MacRitchie, K., Goddard Earth Sciences Data and Information Services Center (GES DISC), Greenbelt, MD, https://doi.org/10.5067/TRMM/TMPA/3H-E/7, 2016. a
Huffman, G. J., Bolvin, D. T., Nelkin, E. J., Wolff, D. B., Adler, R. F., Gu,
G., Hong, Y., Bowman, K. P., and Stocker, E. F.: The TRMM Multisatellite
Precipitation Analysis (TMPA): Quasi-Global, Multiyear,
Combined-Sensor Precipitation Estimates at Fine Scales, J. Hydrometeorol., 8, 38–55, https://doi.org/10.1175/JHM560.1, 2007. a
Huffman, G. J., Adler, R. F., Bolvin, D. T., and Nelkin, E. J.: The TRMM
Multi-Satellite Precipitation Analysis (TMPA), in: Satellite
Rainfall Applications for Surface Hydrology, edited by: Gebremichael,
M. and Hossain, F., Springer Netherlands, Dordrecht, 3–22,
https://doi.org/10.1007/978-90-481-2915-7_1, 2010. a
Huffman, G. J., Stocker, E. F., Bolvin, D. T., Nelkin, E. J., and Tan, J.: GPM IMERG Final Precipitation L3 Half Hourly 0.1 degree × 0.1 degree V06, Greenbelt, MD, Goddard Earth Sciences Data and Information Services Center (GES DISC), https://doi.org/10.5067/GPM/IMERG/3B-HH/06, 2019. a
Jacob, D., Bärring, L., Christensen, O. B., Christensen, J. H., De Castro, M., Déqué, M., Giorgi, F., Hagemann, S., Hirschi, M., Jones, R., Kjellström, E., Lenderink, G., Rockel, B., Sánchez, E., Schär, C., Seneviratne, S. I., Somot, S., van Ulden, A., and van den Hurk, B.: An
inter-comparison of regional climate models for Europe: model performance in
present-day climate, Clim. Change, 81, 31–52, 2007. a
Jacob, D., Elizalde, A., Haensler, A., Hagemann, S., Kumar, P., Podzun, R., Rechid, D., Reca Remedio, A., Saeed, F., Sieck, K., Teichmann, C., and Wilhelm, C.: Assessing the
Transferability of the Regional Climate Model REMO to Different COordinated
Regional Climate Downscaling EXperiment (CORDEX) Regions, Atmosphere, 3,
181–199, https://doi.org/10.3390/atmos3010181, 2012. a
Jerez, S., López-Romero, J. M., Turco, M., Lorente-Plazas, R., Gómez-Navarro,
J. J., Jiménez-Guerrero, P., and Montávez, J. P.: On the Spin-Up Period in
WRF Simulations Over Europe: Trade-Offs Between Length and Seasonality,
J. Adv. Model. Earth Sy., 12, e2019MS001945,
https://doi.org/10.1029/2019MS001945, 2020. a
Kain, J. S.: The Kain–Fritsch Convective Parameterization: An Update,
J. Appl. Meteorol., 43, 170–181,
https://doi.org/10.1175/1520-0450(2004)043<0170:TKCPAU>2.0.CO;2, 2004. a
Kendon, E. J., Ban, N., Roberts, N. M., Fowler, H. J., Roberts, M. J., Chan,
S. C., Evans, J. P., Fosser, G., and Wilkinson, J. M.: Do
Convection-Permitting Regional Climate Models Improve Projections of Future
Precipitation Change?, B. Am. Meteorol. Soc., 98,
79–93, https://doi.org/10.1175/BAMS-D-15-0004.1, 2017. a
Kerandi, N. M., Laux, P., Arnault, J., and Kunstmann, H.: Performance of the
WRF model to simulate the seasonal and interannual variability of
hydrometeorological variables in East Africa: a case study for the Tana
River basin in Kenya, Theor. Appl. Climatol., 130, 401–418,
https://doi.org/10.1007/s00704-016-1890-y, 2017. a, b, c
Kilavi, M., MacLeod, D., Ambani, M., Robbins, J., Dankers, R., Graham, R.,
Titley, H., Salih, A. A. M., and Todd, M. C.: Extreme Rainfall and Flooding
over Central Kenya Including Nairobi City during the Long-Rains Season 2018:
Causes, Predictability, and Potential for Early Warning and Actions,
Atmosphere, 9, 472, https://doi.org/10.3390/atmos9120472, 2018. a, b
Liebmann, B., Hoerling, M. P., Funk, C., Bladé, I., Dole, R. M., Allured,
D., Quan, X., Pegion, P., and Eischeid, J. K.: Understanding Recent
Eastern Horn of Africa Rainfall Variability and Change, J. Climate, 27, 8630–8645, https://doi.org/10.1175/JCLI-D-13-00714.1, 2014. a
Liniger, H., Gikonyo, J., Kiteme, B., and Wiesmann, U.: Assessing and
Managing Scarce Tropical Mountain Water Resources, Mt. Res. Dev., 25, 163–173,
https://doi.org/10.1659/0276-4741(2005)025[0163:AAMSTM]2.0.CO;2, 2005. a, b
Liu, Z.: Comparison of precipitation estimates between Version 7 3-hourly
TRMM Multi-Satellite Precipitation Analysis (TMPA) near-real-time
and research products, Atmos. Res., 153, 119–133,
https://doi.org/10.1016/j.atmosres.2014.07.032, 2015. a
MacMillan, L. and Liniger, H. P.: Monitoring and Modelling for the
Sustainable Management of Water Resources in Tropical Mountain
Basins: The Mount Kenya Example, in: Global Change and Mountain
Regions: An Overview of Current Knowledge, edited by: Huber, U. M.,
Bugmann, H. K. M., and Reasoner, M. A., Springer Netherlands,
Dordrecht, 605–616, https://doi.org/10.1007/1-4020-3508-X_60, 2005. a
Messmer, M., Gómez-Navarro, J. J., and Raible, C. C.: Sensitivity experiments on the response of Vb cyclones to sea surface temperature and soil moisture changes, Earth Syst. Dynam., 8, 477–493, https://doi.org/10.5194/esd-8-477-2017, 2017. a
Messmer, M., González-Rojí, S. J., Raible, C. C., and Stocker, T. F.: Data for publication “Sensitivity of precipitation and temperature over Mount Kenya area to physics parameterization options in a high-resolution model simulation performed with WRFV3.8.1” (Version 1.3) [Data set], Zenodo, https://doi.org/10.5281/zenodo.4090589, 2021. a
Mlawer, E. J., Taubman, S. J., Brown, P. D., Iacono, M. J., and Clough, S. A.:
Radiative transfer for inhomogeneous atmospheres: RRTM, a validated
correlated-k model for the longwave, J. Geophys. Res.-Atmos., 102, 16663–16682, https://doi.org/10.1029/97JD00237, 1997. a
Ngigi, S. N., Savenije, H. H. G., and Gichuki, F. N.: Land use changes and
hydrological impacts related to up-scaling of rainwater harvesting and
management in upper Ewaso Ng'iro river basin, Kenya, Land Use Policy,
24, 129–140, https://doi.org/10.1016/j.landusepol.2005.10.002, 2007. a, b
Nicholson, S. E.: Long-term variability of the East African “short rains”
and its links to large-scale factors, Int. J. Climatol.,
35, 3979–3990, https://doi.org/10.1002/joc.4259, 2015. a
Nicholson, S.: The Turkana low-level jet: mean climatology and association
with regional aridity, Int. J. Climatol., 36, 2598–2614,
https://doi.org/10.1002/joc.4515, 2016a. a
Nicholson, S. E.: An analysis of recent rainfall conditions in eastern
Africa, Int. J. Climatol., 36, 526–532,
https://doi.org/10.1002/joc.4358, 2016b. a, b
Nicholson, S. E.: Climate and climatic variability of rainfall over eastern
Africa, Rev. Geophys., 55, 590–635, https://doi.org/10.1002/2016RG000544,
2017. a, b, c, d
Niu, G.-Y., Yang, Z.-L., Mitchell, K. E., Chen, F., Ek, M. B., Barlage, M.,
Kumar, A., Manning, K., Niyogi, D., Rosero, E., Tewari, M., and Xia, Y.: The
community Noah land surface model with multiparameterization options
(Noah-MP): 1. Model description and evaluation with local-scale measurements,
J. Geophys. Res.-Atmos., 116, D12109,
https://doi.org/10.1029/2010JD015139, 2011. a
Otieno, G., Mutemi, J. N., Opijah, F. J., Ogallo, L. A., and Omondi, M. H.: The
Sensitivity of Rainfall Characteristics to Cumulus Parameterization
Schemes from a WRF Model. Part I: A Case Study Over East
Africa During Wet Years, Pure Appl. Geophys.,
https://doi.org/10.1007/s00024-019-02293-2, 2019. a, b
Paegle, J. and Geisler, J. E.: The Effect of East African Topography on
Flow Driven by Zonally Symmetric Forcing, J.
Atmos. Sci., 43, 1862–1872,
https://doi.org/10.1175/1520-0469(1986)043<1862:TEOEAT>2.0.CO;2, 1986. a
Parry, J.-E., Echeverria, D., Dekens, J., and Maitima, J.: Climate Risks,
Vulnerability and Governance in Kenya: A review, p. 83, available at:
https://www.iisd.org/system/files/publications/climate_risks_kenya.pdf (last access: 29 January 2020), 2012. a
Pleim, J. E.: A Combined Local and Nonlocal Closure Model for the Atmospheric
Boundary Layer. Part I: Model Description and Testing, J. Appl.
Meteorol. Climatol., 46, 1383–1395, https://doi.org/10.1175/JAM2539.1, 2007. a
Pohl, B. and Camberlin, P.: Intraseasonal and interannual zonal circulations
over the Equatorial Indian Ocean, Theor. Appl. Climatol.,
104, 175–191, https://doi.org/10.1007/s00704-010-0336-1, 2011. a, b, c, d
Pohl, B., Crétat, J., and Camberlin, P.: Testing WRF capability in
simulating the atmospheric water cycle over Equatorial East Africa,
Clim. Dynam., 37, 1357–1379, https://doi.org/10.1007/s00382-011-1024-2, 2011. a
Rauscher, S. A., Coppola, E., Piani, C., and Giorgi, F.: Resolution effects on
regional climate model simulations of seasonal precipitation over Europe,
Clim. Dynam., 35, 685–711, 2010. a
R Core Team: R: A Language and Environment for Statistical Computing, R
Foundation for Statistical Computing, Vienna, Austria,
available at: https://www.R-project.org/ (last access: 10 February 2021), 2018. a
Rockel, B. and Geyer, B.: The performance of the regional climate model CLM in
different climate regions, based on the example of precipitation,
Meteorol. Z., 17, 487–498, https://doi.org/10.1127/0941-2948/2008/0297,
2008. a
Rummukainen, M.: State-of-the-art with regional climate models, WIREs Climate
Change, 1, 82–96, https://doi.org/10.1002/wcc.8, 2010. a
Russo, E., Kirchner, I., Pfahl, S., Schaap, M., and Cubasch, U.: Sensitivity studies with the regional climate model COSMO-CLM 5.0 over the CORDEX Central Asia Domain, Geosci. Model Dev., 12, 5229–5249, https://doi.org/10.5194/gmd-12-5229-2019, 2019. a
Russo, E., Sørland, S. L., Kirchner, I., Schaap, M., Raible, C. C., and Cubasch, U.: Exploring the parameter space of the COSMO-CLM v5.0 regional climate model for the Central Asia CORDEX domain, Geosci. Model Dev., 13, 5779–5797, https://doi.org/10.5194/gmd-13-5779-2020, 2020. a
Saji, N., Goswami, B., Vinayachandran, P., and Yamagata, T.: A dipole mode in
the tropical Indian Ocean, Nature, 401, 360–363,
https://doi.org/10.1038/43854, 1999. a
Schmocker, J., Liniger, H. P., Ngeru, J. N., Brugnara, Y., Auchmann, R., and
Brönnimann, S.: Trends in mean and extreme precipitation in the Mount
Kenya region from observations and reanalyses, Int. J.
Climatol., 36, 1500–1514, https://doi.org/10.1002/joc.4438, 2016. a, b, c, d
Schulzweida, U.: CDO User Guide, Zenodo, https://doi.org/10.5281/zenodo.3539275, 2019. a
Skamarock, W. C., Klemp, J. B., Dudhia, J., Gill, D. O., Barker, D. M., Duda,
M. G., yu Huang, X., Wang, W., and Powers, J. G.: A description of the
Advanced Research WRF Version 3, NCAR Technical Note NCAR/TN-475+STR,
https://doi.org/10.5065/D68S4MVH, 2008. a, b
Slingo, J., Spencer, H., Hoskins, B., Berrisford, P., and Black, E.: The
meteorology of the Western Indian Ocean, and the influence of the
East African Highlands, Philos. T. R. Soc. A, 363, 25–42,
https://doi.org/10.1098/rsta.2004.1473, 2005. a
Stratton, R. A., Senior, C. A., Vosper, S. B., Folwell, S. S., Boutle, I. A.,
Earnshaw, P. D., Kendon, E., Lock, A. P., Malcolm, A., Manners, J.,
Morcrette, C. J., Short, C., Stirling, A. J., Taylor, C. M., Tucker, S.,
Webster, S., and Wilkinson, J. M.: A Pan-African
Convection-Permitting Regional Climate Simulation with the Met
Office Unified Model: CP4-Africa, J. Climate, 31,
3485–3508, https://doi.org/10.1175/JCLI-D-17-0503.1, 2018. a, b
Subin, Z. M., Riley, W. J., and Mironov, D.: An improved lake model for climate
simulations: Model structure, evaluation, and sensitivity analyses in CESM1,
J. Adv. Model. Earth Sy., 4, M02001, https://doi.org/10.1029/2011MS000072,
2012. a
Sun, X., Xie, L., Semazzi, F., and Liu, B.: Effect of Lake Surface
Temperature on the Spatial Distribution and Intensity of the
Precipitation over the Lake Victoria Basin, Mon. Weather Rev.,
143, 1179–1192, https://doi.org/10.1175/MWR-D-14-00049.1, 2014. a
Takle, E. S., Roads, J., Rockel, B., Gutowski, W. J., J., Arritt, R. W.,
Meinke, I., Jones, C. G., and Zadra, A.: Transferability Intercomparison: An
Opportunity for New Insight on the Global Water Cycle and Energy Budget,
B. Am. Meteorol. Soc., 88, 375–384,
https://doi.org/10.1175/BAMS-88-3-375, 2007. a
Thiery, W., Davin, E. L., Panitz, H.-J., Demuzere, M., Lhermitte, S., and van
Lipzig, N.: The Impact of the African Great Lakes on the Regional
Climate, J. Climate, 28, 4061–4085,
https://doi.org/10.1175/JCLI-D-14-00565.1, 2015. a
Trewartha, G. T.: The Earth's problem climates, University of Wisconsin
Press, Madison, 1981. a
Ummenhofer, C. C., Gupta, A. S., England, M. H., and Reason, C. J. C.:
Contributions of Indian Ocean Sea Surface Temperatures to Enhanced East
African Rainfall, J. Climate, 22, 993–1013,
https://doi.org/10.1175/2008JCLI2493.1, 2009. a
Velasquez, P., Messmer, M., and Raible, C. C.: A new bias-correction method for precipitation over complex terrain suitable for different climate states: a case study using WRF (version 3.8.1), Geosci. Model Dev., 13, 5007–5027, https://doi.org/10.5194/gmd-13-5007-2020, 2020. a
Vergara-Temprado, J., Ban, N., Panosetti, D., Schlemmer, L., and Schär, C.:
Climate Models Permit Convection at Much Coarser Resolutions
Than Previously Considered, J. Climate, 33, 1915–1933,
https://doi.org/10.1175/JCLI-D-19-0286.1, 2020.
a
Wainwright, C. M., Marsham, J. H., Keane, R. J., Rowell, D. P., Finney, D. L.,
Black, E., and Allan, R. P.: “Eastern African Paradox” rainfall decline
due to shorter not less intense Long Rains, npj Climate and Atmospheric
Science, 2, 1–9, https://doi.org/10.1038/s41612-019-0091-7, 2019. a
Wiesmann, U., Gichuki, F. N., Kiteme, B. P., and Liniger, H.: Mitigating
Conflicts Over Scarce Water Resources in the Highland-Lowland
System of Mount Kenya, Mt. Res. Dev., 20, 10–15,
https://doi.org/10.1659/0276-4741(2000)020[0010:MCOSWR]2.0.CO;2, 2000. a
Williams, A. P. and Funk, C.: A westward extension of the warm pool leads to a
westward extension of the Walker circulation, drying eastern Africa,
Clim. Dynam., 37, 2417–2435, https://doi.org/10.1007/s00382-010-0984-y, 2011. a
Williams, K., Chamberlain, J., Buontempo, C., and Bain, C.: Regional climate
model performance in the Lake Victoria basin, Clim. Dynam., 44,
1699–1713, https://doi.org/10.1007/s00382-014-2201-x, 2015. a, b, c
Woodhams, B. J., Birch, C. E., Marsham, J. H., Bain, C. L., Roberts, N. M., and
Boyd, D. F. A.: What Is the Added Value of a Convection-Permitting
Model for Forecasting Extreme Rainfall over Tropical East
Africa?, Mon. Weather Rev., 146, 2757–2780,
https://doi.org/10.1175/MWR-D-17-0396.1, 2018. a
Woodhams, B. J., Birch, C. E., Marsham, J. H., Lane, T. P., Bain, C. L., and
Webster, S.: Identifying Key Controls on Storm Formation over the
Lake Victoria Basin, Mon. Weather Rev., 147, 3365–3390,
https://doi.org/10.1175/MWR-D-19-0069.1, 2019. a
Wu, M., Nikulin, G., Kjellström, E., Belušić, D., Jones, C., and Lindstedt, D.: The impact of regional climate model formulation and resolution on simulated precipitation in Africa, Earth Syst. Dynam., 11, 377–394, https://doi.org/10.5194/esd-11-377-2020, 2020. a
Yang, Z.-L., Niu, G.-Y., Mitchell, K. E., Chen, F., Ek, M. B., Barlage, M.,
Longuevergne, L., Manning, K., Niyogi, D., Tewari, M., and Xia, Y.: The
community Noah land surface model with multiparameterization options
(Noah-MP): 2. Evaluation over global river basins, J. Geophys. Res.-Atmos., 116, D12110, https://doi.org/10.1029/2010JD015140, 2011. a
Zamuriano, M., Froidevaux, P., Moreno, I., Vuille, M., and Brönnimann, S.: Synoptic and Mesoscale atmospheric features associated with an extreme Snowstorm over the Central Andes in August 2013, Nat. Hazards Earth Syst. Sci. Discuss. [preprint], https://doi.org/10.5194/nhess-2019-286, 2019. a
Short summary
Sensitivity experiments with the WRF model are run to find an optimal parameterization setup for precipitation around Mount Kenya at a scale that resolves convection (1 km). Precipitation is compared against many weather stations and gridded observational data sets. Both the temporal correlation of precipitation sums and pattern correlations show that fewer nests lead to a more constrained simulation with higher correlation. The Grell–Freitas cumulus scheme obtains the most accurate results.
Sensitivity experiments with the WRF model are run to find an optimal parameterization setup for...
