In Hong Kong, cloud amount is reported in oktas hourly by observers at the Hong Kong Observatory Headquarters. The annual mean cloud amount shows a generally increasing trend.
Annual mean cloud amount recorded at the Hong Kong Observatory Headquarters (1961-2023)
Note: The increasing trend (+1.0%/decade) of annual mean cloud amount during 1961-2023 is statistically significant at 5% level.
» Cloud amount data
Clouds and suspended particulates affect the amount of solar radiation reaching the surface.
Annual mean daily total global solar radiation recorded at King's Park (1968-2023)
» Solar radiation data
In general, the amount of evaporation depends on solar radiation, relative humidity and wind speed.
Annual total evaporation recorded at King's Park (1961-2023)
Note: The decreasing trend (-99mm/decade) of annual total evaporation during 1961-2023 is statistically significant at 5% level.
» Evaporation data