Spatial distribution of cloud cover

Abstract

SUMMARYSatellite systems and high-altitude platform systems working in Ka and V bands require the application of adaptive techniques in order to mitigate link degradations caused by atmospheric impairments such as those due to cloud cover. Among these techniques, resource sharing system techniques and site diversity need information on the spatial distribution of impairments caused by cloud cover, including the probability of simultaneous occurrence of adverse conditions in various regions.A study has been performed in Spain, within the framework of COST Action 280, to investigate the large-scale spatial distribution of cloud cover using synoptic meteorological data. Cloud cover distribution for individual sites and the spatial correlation properties for pairs of sites have been investigated. The geographical distributions of the values obtained from the statistical analysis have been represented in maps of contour lines using standard mapping procedures. Correlation parameters are expected to decrease with distance; however, the maps derived taking a given site as reference reveal a significant influence of climatic and geographic factors such as weather fronts, orography or the proximity to the sea. The statistics and maps obtained can be useful to optimize power sharing in multi-beam satellite systems, as suggested in this paper.

A high‐resolution ammonia emission inventory in China

“…However, little ammonia is found in South China and Sichuan province according to satellite observation. The difference between our estimation and satellite observed distributions is first attributed to the fact that satellite monitoring suffers signal impairments caused by meteorological effects such as water vapor, clouds [ Garcia et al , 2008]. In South China and Sichuan province, higher amount of rain and cloud cover might introduce some uncertainties.…”

Spatial multiplexing in optical feeder links for high throughput satellites

“…In general, cloud coverage of the OGSs are correlated and the correlation coefficient can be modelled by r = exp(−d/d 0 ) [13] where d is the distance between two OGSs and d 0 is the cloud correlation distance (∼ 300 km). Based on this model, if the distances between OGSs are large enough (∼ 1000 km) it can be assumed that OGSs will experience independent cloud coverage.…”

Large‐scale correlation of rainfall rate based on data from Spanish sites

“…The correlation coefficient and the statistical dependence index (SDI) are two parameters often used to quantify the degree of correlation among rainfall rate patterns associated to specific sites [5,6]. In [23], both parameters were applied to investigate the spatial characteristics of cloud cover. The first parameter has been calculated for pairs of sites according to the following well-known expression:…”