What are the potential impacts of climate change?
On average, the Earth is warming. Its temperature has already risen by around 0.7°C over the past one hundred years. The rise in temperature is expected to cause a number of impacts such as: • Rising sea levels. A rise in the temperature of ocean waters can cause a rise in sea levels because warmer water takes up a bigger space than cooler water. Warmer temperatures can also lead to the melting of land based ice (such as glaciers and ice sheets). This means that more water is available to flow into the ocean system and cause a rise in sea levels. • Changes in weather patterns such as more severe droughts, heat waves, floods and storms; changes in rainfall patterns; and a higher likelihood of bushfires. • Shifting climate patterns which can have adverse impacts on plants, animals and human health. Increased temperature, changing fire regimes and more regular extreme events, such as hot and dry spells and intense rainfall will impact ecosystems, habitats, food availability and migration
The effects of climate change are already being felt by natural systems in many places. Glaciers in both the northern and southern hemispheres are shrinking, permafrost is thawing, growing seasons are lengthening and animals are shifting their ranges to higher and cooler ground. While increases in intense rainfall events and heatwaves have happened in some regions, there is no clear global trend in smaller-scale severe weather events such as tornadoes, hail or dust storms. Tropical cyclones have increased in intensity since 1970, although there is no clear trend in their numbers. Climate models indicate that further increases in greenhouse gases will lead to continued global warming, more heatwaves, fewer frosts, less snow and a rise in sea level. Rainfall over most parts of the world may increase, but some places in the mid-latitudes, including parts of Australia, may become drier. Vulnerable natural systems, such as alpine fauna and coral reefs, are likely to suffer most as a result
