Weather and climate
Weather describes the conditions of the atmosphere in a place within a short period of time (e.g. several hours, a few days). Climate on the other hand describes the average meteorological conditions in a place over a long period of time. Therefore, climate can be interpreted as the “average weather”. According to the definition given by the World Meteorological Organization (WMO), the reference period for compiling climate statistics should be at least 30 years.
➤ What are conditions of the atmosphere?
Conditions of the atmosphere refer to the meteorological elements such as temperature, relative humidity, precipitation, air pressure, wind direction and wind speed.
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What is climate?
https://public.wmo.int/en/about-us/FAQs/faqs-climate
Example of weather
Fig1.1a shows the regional temperatures of Hong Kong in the afternoon on 26 November 2018.
Fig1.1b shows that the temperature of Tsuen Wan Ho Koon station was 19°C and the relative humidity was 90%.
Fig 1.1c is the image of radar echoes showing that there was rain around Hong Kong.
Fig 1.1a Regional temperatures of Hong Kong (Source: Hong Kong Observatory (HKO)
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| Fig 1.1b Weather conditions at Tsuen Wan Ho Koon station (Source: HKO) | Fig 1.1c Image of radar echoes (Source: HKO) |
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Current weather conditions
https://maps.hko.gov.hk/index_e.html
Example of climate
Using long records of meteorological data, we can calculate the climatological values.
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| Fig 1.1d Using long records of meteorological data, we can calculate the climatological values (Source: HKO) | Fig 1.1e Monthly mean of rainfall in Hong Kong (source: HKO) |
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The ABC’s of Climate
Educational Resources (climate and climate change)
https://www.hko.gov.hk/cis/educationResource_e.htm