The climate system changes in time under the influence of its own internal dynamics and because of external forcings such as volcanic eruptions, solar variations, orbital forcing, and anthropogenic forcings including changes in the composition of the atmosphere and land-use.
According to the IPCC, the scale of recent changes across the climate system as a whole – and the present state of many aspects of the climate system – are unprecedented over many centuries to many thousands of years.
It is unequivocal that human influence has warmed the atmosphere, ocean and land. Widespread and rapid changes in the atmosphere, ocean, cryosphere and biosphere have occurred.
Climate variability and climate change can impact virtually every aspect of society, including food production, health, housing, energy, water resources, safety, tourism, finance, and transportation.
Monitoring climate conditions and predicting what the next season will bring or how our climate will change in the coming years and decades is critical for sustainable development.