Climate change has a number of causes, both natural and man made. However, the last two hundred years have seen changes to the climate occurring more rapidly than ever before. This is predominantly attributed to global warming which in turn has been caused by the burning of fossil fuels since the industrial revolution. The resulting release of greenhouse gases and particulate matter also cause a range of associated processes that also contribute to climate change.
Scientists have used data from ice cores, and other sources to record the planet's climate for the last 800,000 years. This record shows the fluctuations of temperature, rainfall and sea level that have occurred in this time. This cycle of rise and fall is a result of a complex system of events including solar activity, ocean currents, polar ice caps and atmospheric pressure gradients. Events such as meteor strikes and volcanic eruptions also have significant impacts on the global climate and have been known to cause the onset of an ice age. While changes to Earth's climate have always occurred, the frequency of the change in the last two hundred years is alarming scientists and governments around the world.
Global warming has been linked to the rapid change in climate observed since the industrial revolution. The burning of fossil fuels releases greenhouse gases that in turn trap more of the sun's heat in the planet's atmosphere. This raises global temperatures causing a range of other impacts that can affect the climate. One of the most serious impacts of global warming is the melting of ice caps in the north and south poles. They are both important in regulating the planet's climate by maintaining polar albedo (the reflection of solar energy back to space) and the ocean currents that affect major weather systems. As the ice melts less heat is reflected, and the planet becomes warmer. Fresh water entering the ocean in large volumes can also alter ocean currents, further affecting weather systems resulting in changes to the planet's climate.
Changes to the surface of the planet's land masses have also been found to affect climate. Deforestation, urban development and agricultural practices all change the amount of the sun's heat reflected or absorbed by the surface. The carbon cycle is also disrupted; resulting in less atmospheric carbon being sequestered, further increasing global warming that leads to climate change.
The burning of fossil fuels releases particulates into the atmosphere causing acid rain. The particles in the atmosphere can also reduce global warming by reflecting sunlight before it reaches the planet's surface. This process is known as global dimming and has actually been found to counteract the causes of climate change in some instances. Scientists have even suggested purposely releasing sulphur particles into the stratosphere to increase the amount of sunlight reflected back to space. While this would slow climate change, there are a number of negative impacts, particularly on the health of living creatures from the higher levels of particles in the air that they breathe.
Although the planet's climate is influenced by a complex system of natural processes, global warming is the principal cause of recent climate change. Reducing our reliance on fossil fuels, therefore cutting greenhouse gas production is the most important action that humans can take to minimise climate change.