Our World climate is continually changing, alhough we can only see these changes in the climate of the world over long periods of time.
It has been said that “climate is what you expect; weather is what you get”. In other words, you can expect snow in Russia in January, but you may or may not get it on a particular day. Weather describes the condition of the atmosphere over a short period of time e.g. from day to day or week to week, while climate describes average conditions over a longer period of time.
Climate can be viewed as the slowly varying aspects of the air- water-land system. This variability can be seen in the long-term daily, monthly, and yearly averages for different weather conditions. Scientists present this data in many ways. They may use climographs, which show information about specific places, or they may create maps, which can show regional and worldwide data.
The effects of climate can be seen in the distribution of Earth’s life-forms. Temperature ranges and the amount of sunlight and precipitation determine what plants can grow in a region. They also affect which animal species can live there. People are more adaptable; even so, climate can be a limiting factor on the size of a population.
Knowing what to expect is important for planning purposes: The climate of a region affects whether a person needs to lay in supplies of heating oil, stock up on mosquito repellent, or do both. Tables with climate data can be useful to individuals and community leaders alike. Knowing the coldest temperature ever recorded at a city on a particular day can help that city plan for its energy needs; knowing how average annual low temperatures have changed since 1850 in a particular state can provide clues to changes in insect migration. And if you know the average wind conditions at a place you might decide to meet your energy needs with wind power.