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Climate Change in Hong Kong - Cloud amount, solar radiation and evaporation

Climate Change in Hong Kong

Cloud amount, solar radiation and evaporation


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 from 1961 to 2023

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 at King's Park (1968-2023)

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 at King's Park (1961-2023)

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