The Earth's climate is dynamic, changing many times during the planet's history. These changes were caused by natural cycling and large, periodic events such as massive volcanic eruptions and shifts in the Earth's orbit. However for the past 200 years, human activity has created a sustained and growing impact. The burning of fossil fuels and deforestation has changed the temperature and composition of the atmosphere and the ocean and therefore very likely are influencing the Earth's climate. Below are several links to information and activities about climate change, the causes and impacts of climate change, the impacts and role of the ocean in climate change and the impact on the environment.