Climate change – fluctuations of climate of the Earth as a whole or its separate regions over time, expressed in statistically reliable deviations of weather parameters from multiyear values for the time period from decades to millions of years. Changes both in average values of weather parameters and changes in frequency of extreme weather events are taken into account. The science of paleoclimatology studies climate change. Climate change is caused by dynamic processes on Earth, by external influences such as variations in the intensity of solar radiation, and, according to one version, more recently by human activity.
Factors of climate change
Climate change is caused by changes in the Earth’s atmosphere, processes occurring in other parts of the Earth such as oceans, glaciers, and the effects that accompany human activity. External processes that shape the climate are changes in solar radiation and the Earth’s orbit.
Weather is the daily state of the atmosphere. Weather is a chaotic nonlinear dynamic system. Climate is the average state of the weather and is predictable. Climate includes indicators such as average temperature, precipitation, sunny days, and other variables that can be measured at a particular location. However, there are also processes that occur on Earth that can affect the climate.
Glaciers are recognized as one of the most sensitive indicators of climate change. They significantly increase in size during a cooling climate (the so-called “Little Ice Ages”) and decrease during a warming climate. Glaciers grow and melt due to natural changes and under the influence of external influences. In the last century, glaciers were not able to regenerate enough ice during the winters to recover the ice loss during the summer months.
The most significant climatic processes over the past few million years are the change of glacial (glacial epochs) and interglacial (interglacials) epochs of the current ice age, caused by changes in the Earth’s orbit and axis. Changes in continental ice conditions and sea level fluctuations within 130 meters are key consequences of climate change in most regions.
On the scale of decades, climate change may be the result of interactions between the atmosphere and the world’s oceans. Many climate fluctuations, including the best-known El Niño Southern Oscillation and the North Atlantic and Arctic Oscillations, are due in part to the global ocean’s ability to store heat energy and move that energy to different parts of the ocean.
In a more general sense, climate system variability is a form of hysteresis, meaning that the present state of the climate is not only a consequence of certain factors, but also of the entire history of its state. For example, in ten years of drought, lakes partially dry up, plants die, and the area of deserts increases.