Know Climate Change

Basics of Climate Science

Topic Summary

You have completed the topic Basics of Climate Science. Let us summarize the key takeaways from this topic.

  • Weather is the fluctuating state of the atmosphere around us, characterised by the temperature, wind, precipitation, clouds and other weather elements.
  • Climate refers to the average weather in terms of the mean and its variability over a certain time-span and a certain area. Climate is the result of a delicate balance between the several elements including, such as the sun, atmosphere, water systems, living organisms, and topography.
  • The climate system is an interactive system consisting of five major components— atmosphere, hydrosphere, cryosphere, lithosphere, and biosphere.
  • The major layers of the atmosphere include—troposphere, stratosphere, mesosphere, thermosphere, and exosphere.
  • Although the components of the climate system are very different in their composition, physical and chemical properties, structure and behaviour; they are all linked by fluxes of mass, heat and momentum.
  • There are several natural causes that force climate to change.
  • Natural climate variation can be of the following two categories.
    • Natural forcings of the climate system
    • Natural variability of the climate
  • External forcings are essentially linked to changes in the orbital parameters of the earth that control the intensity and location of incident solar radiation, and fluctuations in solar energy.
  • Internal forcings comprise all those that occur within the earth system itself, in particular volcanic activity, fluctuations in ocean circulations and large-scale changes in the marine and terrestrial biosphere or in the cryosphere.
  • Greenhouse effect is a mechanism by which heat energy is trapped by certain gases, such as carbon dioxide, water vapour, and so on.
  • Feedback is the response of the climate to the internal variability of the climate system, and to external forcings.
  • Each individual in today’s world plays a role, directly or indirectly, in contributing his or her bit to climate change.
  • The major human-induced causes include changes in green house gas (GHG) concentrations, changes in aerosol levels, and land use and land cover changes.