Question

It's normal for climates to change naturally over time

Answer 1

Answer:

Explanation:

First we should perhaps ask what we mean by climate change. The Intergovernmental Panel on Climate Change defines climate change as:

a change in the state of the climate that can be identified by changes in the mean and/or the variability of its properties and that persists for an extended period, typically decades or longer.

The causes of climate change can be any combination of:

Internal variability in the climate system, when various components of the climate system – like the atmosphere and ocean – vary on their own to cause fluctuations in climatic conditions, such as temperature or rainfall. These internally-driven changes generally happen over decades or longer; shorter variations such as those related to El Niño fall in the bracket of climate variability, not climate change.

Natural external causes such as increases or decreases in volcanic activity or solar radiation. For example, every 11 years or so, the Sun’s magnetic field completely flips and this can cause small fluctuations in global temperature, up to about 0.2 degrees. On longer time scales – tens to hundreds of millions of years – geological processes can drive changes in the climate, due to shifting continents and mountain building.

Human influence through greenhouse gases (gases that trap heat in the atmosphere such as carbon dioxide and methane), other particles released into the air (which absorb or reflect sunlight such as soot and aerosols) and land-use change (which affects how much sunlight is absorbed on land surfaces and also how much carbon dioxide and methane is absorbed and released by vegetation and soils).