Global Drought and Flood. Группа авторов

Читать онлайн книгу.

Global Drought and Flood - Группа авторов


Скачать книгу
satellites rather than a global composite of all available geostationary data sets. The global ALEXI model ESI product is available at a spatial resolution of 5 km and a period of record from 2001 to 2014, reprocessed to weekly time steps and 25 km resolution for this study.

      Assuming that the three kinds of errors are uncorrelated and

      (2.31)equation

      we obtain the RMSE values for MWSM ( ξ MWSM), ESI ( ξ ESI), and NLSM ( ξ NLSM) as the following (Miralles et al., 2010; Scipal et al., 2008; Stoffelen, 1998):

      (2.32)equation

      (2.33)equation

      (2.34)equation

      Thus, based on the TCEM, the monthly RMSEs for each of the data sets can be estimated grid by grid regionally or globally.

      (Source: From Yin, J., Zhan, X., Hain, C. R., Liu, J., & Anderson, M. C. (2018). A Method for Objectively Integrating Soil Moisture Satellite Observations and Model Simulations Toward a Blended Drought Index. Water Resources Research, 54(9), 6772–6791. © 2018, John Wiley & Sons.)

Schematic illustration of monthly BDI_b for the Russian (from 40°N, 20°E to 70°N, 80°E) domain in 2010.

      (Source: From Yin, J., Zhan, X., Hain, C. R., Liu, J., & Anderson, M. C. (2018). A Method for Objectively Integrating Soil Moisture Satellite Observations and Model Simulations Toward a Blended Drought Index. Water Resources Research, 54(9), 6772–6791. © 2018, John Wiley & Sons.)

      In this chapter we briefly reviewed the history of studies of estimating land surface evapotranspiration at local to global scales using remote sensing approaches. The thermal remote sensing approach using the ALEXI model is categorized as probably one of the most reliable. Based on the ALEXI model the GET‐D product system using GOES‐13 and GOES‐15 observations has been developed and made operational at the NESDIS of NOAA. Upgrading the GET‐D system to use the most recently installed GOES‐16 and GOES‐17 observations is ongoing. For global remote sensing of ET and monitoring of drought based on ET estimates, the ALEXI model using the thermal observations from NOAA operational observations of VIIRS onboard the Suomi National Polar‐orbiting Partnership and Joint Polar Satellite System satellites has been demonstrated to be promising (Hain et al., 2017). More intercomparison and validation studies using approaches based on the ALEXI model, the PM equation, the PT equation, and other methods for globally estimating and monitoring drought are needed.

Schematic illustration of monthly BDI_b for the southern United States (from 25°N, -115°W to 40°N, -90°W) domain in 2011.

      (Source: From Yin, J., Zhan, X., Hain, C. R., Liu, J., & Anderson, M. C. (2018). A Method for Objectively Integrating Soil Moisture Satellite Observations and Model Simulations Toward a Blended Drought Index. Water Resources Research, 54(9), 6772–6791. © 2018, John Wiley & Sons.)

      1 Allen, R., Irmak, A., Trezza, R., Hendrickx, J.M.H., Bastiaanssen, W., & Kjaersgaard, J. (2011). Satellite‐based ET estimation in agriculture using SEBAL and METRIC. Hydrological Processes, 25(26), 4011–4027. doi:10.1002/hyp.8408

      2 Allen, R.G., Tasumi, M., Morse, A., & Trezza, R. (2005). A Landsat‐based energy balance and evapotranspiration model


Скачать книгу