section_path: Challenges and problems/Climate change
section_name: Climate change
paragraph_text: Climate change
  
  Climate change and global warming reflects the notion of the modern climate. The changes of climate over the past century, have been attributed to various factors which have resulted in a global warming. This warming is the increase in the average temperature of the Earth's near-surface air and oceans since the mid-20th century and its projected continuation. Some effects on both the natural environment and human life are, at least in part, already being attributed to global warming. A 2001 report by the Intergovernmental Panel on Climate Change suggests that glacier retreat, ice shelf disruption such as that of the Larsen Ice Shelf, sea level rise, changes in rainfall patterns, and increased intensity and frequency of extreme weather events are attributable in part to global warming. Other expected effects include water scarcity in some regions and increased precipitation in others, changes in mountain snowpack, and adverse health effects from warmer temperatures.
  
  It is usually impossible to connect specific weather events to human impact on the world. Instead, such impact is expected to cause changes in the overall distribution and intensity of weather events, such as changes to the frequency and intensity of heavy precipitation. Broader effects are expected to include glacial retreat, Arctic shrinkage, and worldwide sea level rise. Other effects may include changes in crop yields, addition of new trade routes, species extinctions, and changes in the range of disease vectors. Until 2009, the Arctic Northwest Passage pack ice prevented regular marine shipping throughout most of the year in this area, but climate change has reduced the pack ice, and this Arctic shrinkage made the waterways more navigable.