Global warming is caused by carbon emissions thickening the atmosphere and trapping more of the sun's rays, increasing Earth's temperatures. As the effects of global warming intensify, glaciers and ice sheets are melting, cyclones and hurricanes are becoming more severe, and heat waves and droughts are occurring more frequently. If no action is taken to reduce carbon emissions, the global temperature could increase beyond any point in Earth's history, with devastating consequences such as sea level rise flooding coastal cities and disruptions to ocean currents. Individual actions like changing light bulbs and reducing driving can help address the problem, as well as volunteering with environmental groups and encouraging others.