Numerical Models
Until now, Dr. Niwano has developed the physical snowpack model SMAP, the polar regional climate model NHM-SMAP, and the detailed atmosphere-snow coupled model for Japan (LFM-SMAP).
The physical snowpack model SMAP
References:
Niwano, M., T. Aoki, K. Kuchiki, M. Hosaka, Y. Kodama, S. Yamaguchi, H. Motoyoshi, and Y. Iwata, 2014: Evaluation of updated physical snowpack model SMAP, Bull. Glaciol. Res., 32, 65-78, https://doi.org/10.5331/bgr.32.65
Niwano, M., T. Aoki, K. Kuchiki, M. Hosaka, and Y. Kodama, 2012: Snow Metamorphism and Albedo Process (SMAP) model for climate studies: Model validation using meteorological and snow impurity data measured at Sapporo, Japan, J. Geophys. Res., 117, F03008, https://doi.org/10.1029/2011JF002239
The SMAP model has participated in the snow model inter-comparison project ESM-SnowMIP:
Krinner, G., C. Derksen, R. Essery, M. Flanner, S. Hagemann, M. Clark, A. Hall, H. Rott, C. Brutel-Vuilmet, H. Kim, C. B. Ménard, L. Mudryk, C. Thackeray, L. Wang, G. Arduini, G. Balsamo, P. Bartlett, J. Boike, A. Boone, F. Chéruy, J. Colin, M. Cuntz, Y. Dai, B. Decharme, J. Derry, A. Ducharne, E. Dutra, X. Fang, C. Fierz, J. Ghattas, Y. Gusev, V. Haverd, A. Kontu, M. Lafaysse, R. Law, D. Lawrence, W. Li, T. Marke, D. Marks, M. Ménégoz, O. Nasonova, T. Nitta, M. Niwano, J. Pomeroy, M. S. Raleigh, G. Schaedler, V. Semenov, T. G. Smirnova, T. Stacke, U. Strasser, S. Svenson, D. Turkov, T. Wang, N. Wever, H. Yuan, W. Zhou, and D. Zhu, 2018: ESM-SnowMIP: assessing snow models and quantifying snow-related climate feedbacks, Geosci. Model Dev., 11, 5027-5049, https://doi.org/10.5194/gmd-11-5027-2018.
Ménard, C. B., Essery, R., Barr, A., Bartlett, P., Derry, J., Dumont, M., Fierz, C., Kim, H., Kontu, A., Lejeune, Y., Marks, D., Niwano, M., Raleigh, M., Wang, L., and Wever, N., 2019: Meteorological and evaluation datasets for snow modelling at ten reference sites: description of in situ and bias-corrected reanalysis data, Earth Syst. Sci. Data, 11, 865-880, https://doi.org/10.5194/essd-11-865-2019.
Menard, C. B., Essery, R., Krinner, G., Arduini, G., Bartlett, P., Boone, A., Brutel-Vuilmetm, C., Burke, E., Cuntz, M., Dai, Y., Decharmem, B., Dutra, E., Fang, X., Fierz, C., Gusev, Y., Hagemann, S., Haverd, V., Kim, H., Lafaysse, M., Marke, T., Nasonova, O., Nitta, T., Niwano, M., Pomeroy, J., Schädler, G., Semenov, V., Smirnova, T., Strasser, U., Swenson, S., Turkov, D., Wever, N., and Yuan, H., 2020 : Scientific and human errors in a snow model intercomparison. Bull. Amer. Meteor. Soc., 125, in press, https://doi.org/10.1175/BAMS-D-19-0329.1.
The SMAP model has contributed to the estimation of concentration of light absorbing impurities in the surface snow through melt and sublimation/evaporation at Greenland and Sapporo, Japan:
Kuchiki, K., T. Aoki, M. Niwano, S. Matoba, Y. Kodama, and K. Adachi, 2015: Elemental carbon, organic carbon, and dust concentrations in snow measured with thermal optical method and filter weighing: variations during 2007-2013 winters in Sapporo, Japan. J. Geophys. Res. Atmos., 120, 868-882, https://doi.org/10.1002/2014JD022144.
Aoki, T., S. Matoba, S. Yamaguchi, T. Tanikawa, M. Niwano, K. Kuchiki, K. Adachi, J. Uetake, H. Motoyama, and M. Hori, 2014: Light-absorbing snow impurity concentrations measured on Northwest Greenland ice sheet in 2011 and 2012. Bull. Glaciol. Res., 32, 21-31, https://doi.org/10.5331/bgr.32.21.
The polar regional climate model NHM-SMAP
References:
Niwano, M., T. Aoki, A. Hashimoto, S. Matoba, S. Yamaguchi, T. Tanikawa, K. Fujita, A. Tsushima, Y. Iizuka, R. Shimada, and M. Hori, 2018: NHM–SMAP: spatially and temporally high-resolution nonhydrostatic atmospheric model coupled with detailed snow process model for Greenland Ice Sheet, The Cryosphere, 12, 635-655, https://doi.org/10.5194/tc-12-635-2018
Niwano, M., Hashimoto, A., and Aoki, T., 2019: Cloud-driven modulations of Greenland ice sheet surface melt, Sci. Rep., 9, 10380, https://doi.org/10.1038/s41598-019-46152-5.
NHM-SMAP has participated in the Greenland ice sheet surface mass balance model inter-comparison project GrSMBMIP
Fettweis, X., Hofer, S., Krebs-Kanzow, U., Amory, C., Aoki, T., Berends, C. J., Born, A., Box, J. E., Delhasse, A., Fujita, K., Gierz, P., Goelzer, H., Hanna, E., Hashimoto, A., Huybrechts, P., Kapsch, M.-L., King, M. D., Kittel, C., Lang, C., Langen, P. L., Lenaerts, J. T. M., Liston, G. E., Lohmann, G., Mernild, S. H., Mikolajewicz, U., Modali, K., Mottram, R. H., Niwano, M., Noël, B., Ryan, J. C., Smith, A., Streffing, J., Tedesco, M., van de Berg, W. J., van den Broeke, M., van de Wal, R. S. W., van Kampenhout, L., Wilton, D., Wouters, B., Ziemen, F., and Zolles, T., 2020: GrSMBMIP: intercomparison of the modelled 1980–2012 surface mass balance over the Greenland Ice Sheet. The Cryosphere, 14, 3935–3958, https://doi.org/10.5194/tc-14-3935-2020. Open Access
Detailed atmosphere-snow coupled model for Japan (LFM-SMAP)
This model has been utilized for the real-time snow analysis and forecast by Japan Meteorological Agency (JMA) since 2022 October. The real-time information by JMA can be found in the following link:
https://www.jma.go.jp/bosai/en_snow/
References:
Niwano, M., Suya, M., Nagaya, K., Yamaguchi, S., Matoba, S., Harada, I., and Ohkawara, N., 2022: Estimation of seasonal snow mass balance all over Japan using a high-resolution atmosphere-snow model chain, SOLA, 18, 193-198, https://doi.org/10.2151/sola.2022-031.