Abstract. The main drawback of the reconstruction of high-resolution
distributed global radiation (Rg) time series in mountainous semiarid
environments is the common lack of station-based solar radiation registers.
This work presents 19 years (2000–2018) of high-spatial-resolution (30 m) daily, monthly, and annual global radiation maps derived using the
GIS-based model proposed by Aguilar et al. (2010) in a mountainous area in
southern Europe: Sierra Nevada (SN) mountain range (Spain). The model was
driven by in situ daily global radiation measurements, from 16 weather
stations with historical records in the area; a 30 m digital elevation model;
and 240 cloud-free Landsat images. The applicability of the modeling scheme
was validated against daily global radiation records at the weather
stations. Mean RMSE values of 2.63 MJ m−2 d−1 and best
estimations on clear-sky days were obtained. Daily Rg at weather
stations revealed greater variations in the maximum values but no clear
trends with altitude in any of the statistics. However, at the monthly and
annual scales, there is an increase in the high extreme statistics with the
altitude of the weather station, especially above 1500 m a.s.l. Monthly
Rg maps showed significant spatial differences of up to 200 MJ m−2 per month that clearly followed the terrain configuration. July and
December were clearly the months with the highest and lowest values of
Rg received, and the highest scatter in the monthly Rg values was
found in the spring and fall months. The monthly Rg distribution was
highly variable along the study period (2000–2018). Such variability,
especially in the wet season (October–May), determined the interannual
differences of up to 800 MJ m−2 yr−1 in the incoming global
radiation in SN. The time series of the surface global radiation datasets
here provided can be used to analyze interannual and seasonal variation
characteristics of the global radiation received in SN with high spatial
detail (30 m). They can also be used as cross-validation reference data for
other global radiation distributed datasets generated in SN with different
spatiotemporal interpolation techniques. Daily, monthly, and annual
datasets in this study are available at https://doi.org/10.1594/PANGAEA.921012 (Aguilar et al., 2021).
Review of the submitted article "Two decades of distributed global radiation time series across amountainous semiarid area (Sierra Nevada, Spain)" by Cristina Aguilar et al.
