What is climate?


Understanding climate is a useful starting point for understanding climate change. The words climate’ and ‘weather are sometimes used interchangeably, but they are in fact different, though related, phenomena.


Expected sesonal effects of El Nino and La Nina
Expected seasonal effects of El Niño (warm episodes) across the globe during December− February (top) and expected seasonal effects of La Niña (cold episodes) during the same time period(bottom)
Source: ClimateDiagnosticsCenter, NOAA.

Several geographic factors influence climate, including latitude and altitude, continentality, distance from the ocean, mountain barriers, solar radiation, ocean currents, volcanic activity, and prevailing winds.  Climate is also influenced by changes in the Earth’s orbit around the sun and the energy the planet gets from the sun.  All of these geographic factors are fairly constant; however, where there are changes, these take place over the long term.


The interaction between the ocean and the atmosphere (ocean-atmosphere dynamics), has an impact on climate as well. One such phenomenon that has a major influence on climate in the UKOTs is the El Niño - Southern Oscillation (ENSO)or El Niño), as the phenomenon is commonly known.

Within each climate zone, the people, plants and animals are adapted to the range of conditions found there. The plants and animals that are native to the tropical climate of the Turks and Caicos Islands thrive there, but would find the Antarctic climate of the British Antarctic Territory hostile, and vice versa.  When change occurs within a climate zone, however, human and ecological systems are challenged by conditions that are on the edge of, or outside, the normal range. Over time, this can put stress on systems or modify them.


Human and biological systems are so interlinked that a change in one area of either system has knock-on effects on others. Human activity is greatly influenced by climate. “Climate shapes ecosystems and species, determines the types of engineering structures we build (from houses to bridges), and affects our culture, our moods, our leisure pursuits”.