[20210511]IF11446_天气和气候变化：有什么区别？.pdf

https:/crsreports.congress.gov Updated May 11, 2021Weather and Climate Change: Whats the Difference?With much discussion of climate change in Congress, in the news, and among constituents, some commonly used words may be misunderstood or misused. Below are explanations of several key terms: weather, climate, climate variability, and climate change, as well as some associated concepts. Weather is the state of the atmosphere at a specific place and time, described by such conditions as temperature, precipitation, humidity, cloudiness, and wind speed. Weather can include conditions of the Earths water and land surfaces as well, with such variables as wave height and snow cover. Weather conditions can vary rapidly or last up to a few days in the mid-latitudes. NOAA compiles observations from weather stations around the United States, in the oceans, from international sources, and from other federal agencies. NOAA analyzes historical weather data and provides multiday forecasts or seasonal outlooks. Climate is defined by the long-term statistics of weather compiled for a specified place (Figure 1), including the globe. For example, climate would include the maximum hourly precipitation