Evaluation of bias and uncertainty in snow depth reanalysis data over South Korea

Hyunho Jeon; Seulchan Lee; Yangwon Lee; Jinsoo Kim; Minha Choi

doi:10.3741/JKWRA.2023.56.9.543

All Issue

2023 Vol.56, Issue 9 Preview Page Next Page

Research Article

Evaluation of bias and uncertainty in snow depth reanalysis data over South Korea 한반도 적설심 재분석자료의 오차 및 불확실성 평가

30 September 2023. pp. 543-551

PDF XML

Abstract

Snow is an essential climate factor that affects the climate system and surface energy balance, and it also has a crucial role in water balance by providing solid water stored during the winter for spring runoff and groundwater recharge. In this study, statistical analysis of Local Data Assimilation and Prediction System (LDAPS), Modern.-Era Retrospective Analysis for Research and Applications, version 2 (MERRA-2), and ERA5-Land snow depth data were used to evaluate the applicability in South Korea. The statistical analysis between the Automated Synoptic Observing System (ASOS) ground observation data provided by the Korea Meteorological Administration (KMA) and the reanalysis data showed that LDAPS and ERA5-Land were highly correlated with a correlation coefficient of more than 0.69, but LDAPS showed a large error with an RMSE of 0.79 m. In the case of MERRA-2, the correlation coefficient was lower at 0.17 because the constant value was estimated continuously for some periods, which did not adequately simulate the increase and decrease trend between data. The statistical analysis of LDAPS and ASOS showed high and low performance in the nearby Gangwon Province, where the average snowfall is relatively high, and in the southern region, where the average snowfall is low, respectively. Finally, the error variance between the four independent snow depth data used in this study was calculated through triple collocation (TC), and a merged snow depth data was produced through weighting factors. The reanalyzed data showed the highest error variance in the order of LDAPS, MERRA-2, and ERA5-Land, and LDAPS was given a lower weighting factor due to its higher error variance. In addition, the spatial distribution of ERA5-Land snow depth data showed less variability, so the TC-merged snow depth data showed a similar spatial distribution to MERRA-2, which has a low spatial resolution. Considering the correlation, error, and uncertainty of the data, the ERA5-Land data is suitable for snow-related analysis in South Korea. In addition, it is expected that LDAPS data, which is highly correlated with other data but tends to be overestimated, can be actively utilized for high-resolution representation of regional and climatic diversity if appropriate corrections are performed.

Keywords

Snow depth

ASOS

LDAPS

MERRA-2

ERA5-Land

Triple collocation

눈은 기후계와 지표면 에너지 평형에 영향을 끼치는 필수 기후 인자이며, 겨울 동안 저장한 고체 형태의 물을 봄에 유출, 지하수 함양 등에 제공하여 물 평형에도 결정적인 역할을 한다. 본 연구에서는 Local Data Assimilation and Prediction System (LDAPS), Modern.-Era Retrospective Analysis for Research and Applications, version 2 (MERRA-2), ERA5-Land 적설심 자료의 통계 분석을 통해 남한에서의 활용 가능성을 평가하였다. 기상청에서 제공하는 Automated Synoptic Observing System (ASOS) 지상관측자료와 재분석자료간의 통계분석 결과, LDAPS와 ERA5-Land의 상관계수가 0.69 이상으로 상관성이 높게 나타났으나 LDAPS는 RMSE가 0.79 m로 오차가 크게 나타났다. MERRA-2의 경우 일부 기간 동안 일정한 값이 연속적으로 산출되어 자료간 증감 추이를 적절하게 모의하지 못하였기에 상관계수가 0.17로 상관성이 낮게 나타났다. LDAPS와 ASOS의 지점별 통계분석 결과 상대적으로 평균 강설량이 높게 나타나는 강원도 인근에서 성능이 높게 나타났으며, 평균 강설량이 낮게 나타나는 남부 지역에서 성능이 낮게 나타났다. 마지막으로, triple collocation (TC)를 통해 본 연구에서 활용된 4개의 독립적인 적설심자료 간의 오차 분산을 산정하였으며, 나아가 가중치 산정을 통해 융합된 적설심 자료를 생산하였다. 재분석자료는 LDAPS, MERRA-2, ERA5-Land 순으로 오차 분산이 높게 나타났으며, LDAPS의 경우 오차 분산이 높게 산정되어 가중치가 낮게 산정되었다. 또한, ERA5-Land 적설심 자료의 공간 분포가 변동성이 적게 나타나, TC로 융합된 적설심 자료는 저해상도 영상인 MERRA-2와 유사한 공간 분포가 나타났다. 자료의 상관성, 오차, 불확실성을 고려하였을 때, ERA5-Land 자료가 남한을 대상으로 적설 관련 분석을 하기 적합한 것으로 판단된다. 또한, 타 자료와 경향성은 높게 나타나나 과대 산정되는 경향이 있는 LDAPS 자료를 대상으로 적절한 보정이 수행될 시, 지역 및 기후적 다양성을 높은 해상도로 표출할 수 있는 LDAPS 자료를 적극적으로 활용할 수 있을 것으로 기대된다.

키워드

적설심

ASOS

LDAPS

MERRA-2

ERA5-Land

Triple collocation

References

Baik, J., Cho, S., Lee, S., and Choi, M. (2019b). "Analysis on adequacy of the satellite soil moisture data (AMSR2, ASCAT, and ESACCI) in Korean Peninsula: With classification of freezing and melting periods." Korean Journal of Remote Sensing, Vol. 35, No. 5, pp. 625-636.

Baik, J., Jeong, J., Park, J., and Choi, M. (2019a). "A study on the analyzing of uncertainty for actual evapotranspiration: Flux tower, satellite-based and reanalysis based dataset." Journal of Korea Water Resources Association, Vol. 52, No. 1, pp. 11-19.

Baik, J., Park, J., Hao, Y., and Choi, M. (2022). "Integration of multiple drought indices using a triple collocation approach." Stochastic Environmental Research and Risk Assessment, Vol. 36, No. 4, pp. 1177-1195. 10.1007/s00477-021-02044-7

Byun, K., and Choi, M. (2014). "Uncertainty of snow water equivalent retrieved from AMSR‐E brightness temperature in northeast Asia." Hydrological Processes, Vol. 28, No. 7, pp. 3173-3184. 10.1002/hyp.9846

Cheong, S.H., Byun, K.Y., and Lee, T.Y. (2006). "Classification of snowfalls over the Korean Peninsula based on developing mechanism." Atmosphere, Vol. 16, No. 1, pp. 33-48.

Cohen, J., and Rind, D. (1991). "The effect of snow cover on the climate." Journal of Climate, Vol. 4, No. 7, pp. 689-706. 10.1175/1520-0442(1991)004<0689:TEOSCO>2.0.CO;2

Dong, C. (2018). "Remote sensing, hydrological modeling and in situ observations in snow cover research: A review." Journal of Hydrology, Vol. 561, pp. 573-583. 10.1016/j.jhydrol.2018.04.027

Dong, C., and Menzel, L. (2017). "Snow process monitoring in montane forests with time lapse photography." Hydrological Processes, Vol. 31, No. 16, pp. 2872-2886. 10.1002/hyp.11229

Dong, J., Lei, F., and Wei, L. (2020). "Triple collocation based multi-source precipitation merging." Frontiers in Water, Vol. 2, 1. 10.3389/frwa.2020.00001

Fang, Y., Liu, Y., and Margulis, S.A. (2022). "A western United States snow reanalysis dataset over the Landsat era from water years 1985 to 2021." Scientific Data, Vol. 9, No. 1, 677. 10.1038/s41597-022-01768-736344572PMC9640559

Faranda, D. (2020). "An attempt to explain recent changes in European snowfall extremes." Weather and Climate Dynamics, Vol. 1, No. 2, pp. 445-458. 10.5194/wcd-1-445-2020

Gao, Y., Xie, H., Lu, N., Yao, T., and Liang, T. (2010). "Toward advanced daily cloud-free snow cover and snow water equivalent products from Terra - Aqua MODIS and Aqua AMSR-E measurements." Journal of Hydrology, Vol. 385, No. 1-4, pp. 23-35. 10.1016/j.jhydrol.2010.01.022

Hu, Z., Dietz, A., Zhao, A., Uereyen, S., Zhang, H., Wang, M., Mederer, P., and Kuenzer, C. (2020). "Snow moving to higher elevations: Analyzing three decades of snowline dynamics in the alps." Geophysical Research Letters, Vol. 47, No. 12, pp. 1-11. 10.1029/2019GL085742

Huang, C.L., Wang, H.W., and Hou, J.L. (2015). "Estimating spatial distribution of daily snow depth with kriging methods: Combination of MODIS snow cover area data and ground-based observations." The Cryosphere Discussions, Vol. 9, No. 5, pp. 4997-5020. 10.5194/tcd-9-4997-2015

Kim, B.G., Kim, M.G., Kwon, T.Y., Park, G.M., Han, Y.D., Kim, S.B., and Chang, K.H. (2021). "Observation and understanding of snowfall characteristics in the Yeongdong region." Atmosphere, Vol. 31, No. 4, pp. 461-472.

Lei, Y., Pan, J., Xiong, C., Jiang, L., and Shi, J. (2023). "Snow depth and snow cover over the Tibetan Plateau observed from space in against ERA5: Matters of scale." Climate Dynamics, Vol. 60, No. 5-6, pp. 1523-1541. 10.1007/s00382-022-06376-0

Li, Q., Yang, T., and Li, L. (2022). "Evaluation of snow depth and snow cover represented by multiple datasets over the Tianshan Mountains: Remote sensing, reanalysis, and simulation." International Journal of Climatology, Vol. 42, No. 8, pp. 4223-4239. 10.1002/joc.7459

Liu, Y., and Margulis, S.A. (2019). "Deriving bias and uncertainty in MERRA-2 snowfall precipitation over high mountain Asia." Frontiers in Earth Science, Vol. 7, 280. 10.3389/feart.2019.00280

Liu, Y., Weerts, A.H., Clark, M., Hendricks Franssen, H.-J., Kumar, S., Moradkhani, H., Seo, D.-J., Schwanenberg, D., Smith, P., van Dijk, A.I.J.M., van Velzen, N., He, M., Lee, H., Noh, S.J., Rakovec, O., and Restrepo, P. (2012). "Advancing data assimilation in operational hydrologic forecasting: Progresses, challenges, and emerging opportunities." Hydrology and Earth System Sciences, Vol. 16, No. 10, pp. 3863-3887. 10.5194/hess-16-3863-2012

Ma, H., Zhang, G., Mao, R., Su, B., Liu, W., and Shi, P. (2023). "Snow depth variability across the Qinghai Plateau and its influencing factors during 1980-2018." International Journal of Climatology, Vol. 43, No. 2, pp. 1094-1111. 10.1002/joc.7883

Mankin, J.S., Viviroli, D., Singh, D., Hoekstra, A.Y., and Diffenbaugh, N.S. (2015). "The potential for snow to supply human water demand in the present and future." Environmental Research Letters, Vol. 10, No. 11, 114016. 10.1088/1748-9326/10/11/114016

Meromy, L., Molotch, N.P., Link, T.E., Fassnacht, S.R., and Rice, R. (2013). "Subgrid variability of snow water equivalent at operational snow stations in the western USA." Hydrological Processes, Vol. 27, No. 17, pp. 2383-2400. 10.1002/hyp.9355

Nolin, A.W. (2010). "Recent advances in remote sensing of seasonal snow." Journal of Glaciology, Vol. 56, No. 200, pp. 1141-1150. 10.3189/002214311796406077

O'Gorman, P.A. (2014). "Contrasting responses of mean and extreme snowfall to climate change." Nature, Vol. 512, No. 7515, pp. 416-418. 10.1038/nature1362525164753

Painter, T.H., Roberts, D.A., Green, R.O., and Dozier, J. (1998). "The effect of grain size on spectral mixture analysis of snow-covered area from AVIRIS data." Remote Sensing of Environment, Vol. 65, No. 3, pp. 320-332. 10.1016/S0034-4257(98)00041-8

Park, J., Baik, J., and Choi, M. (2023). "Triple collocation-based multi-source evaporation and transpiration merging." Agricultural and Forest Meteorology, 331, 109353. 10.1016/j.agrformet.2023.109353

Qiao, D., Li, Z., Zeng, J., Liang, S., McColl, K.A., Bi, H.,Zhou, J., and Zhang, P. (2022). "Uncertainty characterization of ground-based, satellite, and reanalysis snow depth products using extended triple collocation." Water Resources Research, Vol. 58, No. 4, e2021WR030895. 10.1029/2021WR030895

Reichle, R.H., Draper, C.S., Liu, Q., Girotto, M., Mahanama, S.P., Koster, R.D., and De Lannoy, G.J. (2017). "Assessment of MERRA-2 land surface hydrology estimates." Journal of Climate, Vol. 30, No. 8, pp. 2937-2960. 10.1175/JCLI-D-16-0720.1

Schmugge, T.J., Kustas, W.P., Ritchie, J.C., Jackson, T.J., and Rango, A. (2002). "Remote sensing in hydrology." Advances in Water Resources, Vol. 25, No. 8-12, pp. 1367-1385. 10.1016/S0309-1708(02)00065-9

Stoffelen, A. (1998). "Toward the true near‐surface wind speed: Error modeling and calibration using triple collocation." Journal of Geophysical Research: Oceans, Vol. 103, No. C4, pp. 7755-7766. 10.1029/97JC03180

Tait, A.B., Hall, D.K., Foster, J.L., and Armstrong, R.L. (2000). "Utilizing multiple datasets for snow-cover mapping." Remote Sensing of Environment, Vol. 72, No. 1, pp. 111-126. 10.1016/S0034-4257(99)00099-1

Wang, C.H., Yang, K., Li, Y.L., Wu, D., and Bo, Y. (2017). "Impacts of spatiotemporal anomalies of Tibetan Plateau snow cover on summer precipitation in eastern China." Journal of Climate, Vol. 30, No. 3, pp. 885-903. 10.1175/JCLI-D-16-0041.1

Xu, W.F., Ma, L.J., Ma, M.N., Zhang, H.C., and Yuan, W.P. (2017). "Spatial-temporal variability of snow cover and depth in the Qinghai-Tibetan Plateau." Journal of Climate, Vol. 30, No. 4, pp. 1521-1533. 10.1175/JCLI-D-15-0732.1

Information

Publisher :KOREA WATER RESOURECES ASSOCIATION
Publisher(Ko) :한국수자원학회
Journal Title :Journal of Korea Water Resources Association
Journal Title(Ko) :한국수자원학회 논문집
Volume : 56
No :9
Pages :543-551
Received Date : 2023-06-23
Revised Date : 2023-08-17
Accepted Date : 2023-08-18
DOI :https://doi.org/10.3741/JKWRA.2023.56.9.543

Journal of Korea Water Resources Association ISSN:2799-8746(Print) 2799-8754(Online) 한국수자원학회 논문집

All Issue