Hobbies And Interests
Global Warming
According to the 2007 climate change assessment report by the Intergovernmental Panel on Climate Change, global warming has already decreased snow cover in certain parts of the globe and contributed to an increase in average mean temperatures throughout the year. Global warming projections suggest that between 2011 and 2030, average temperatures will rise between 0.64 and 0.69 degrees Celsius. During the mid -- 2046 to 2069 -- and late -- 2090 to 2099 -- century periods, temperatures are expected to rise by a higher number of degrees and be more reliant on future changes in the climate. From this data, it can be posited that Earth's biodiversity will markedly change due to these higher temperatures.
Marine Biodiversity
Global warming's effects on the world's oceans include rising water temperatures, rising sea levels and the migration of some marine species. In 1999, a warming event in the northwest Mediterranean caused massive mortality rates of 16 species that lived along the shores. Global temperature increases can cause similar effects on a larger scale, which can then affect other species directly related via the food chain. Corals can also be affected by warming. Higher water temperatures can cause a loss of symbiotic zooxanthellae, which can lead to coral death. Coral death can affect the many species that make their homes only in coral reefs. Many larger species will migrate to cooler waters nearer to the poles, after time, which will affect the species that already live there and cannot migrate farther.
Climatic Envelope
Scientists use a climatic envelope, or bioclimatic envelope, to estimate the effect of climate change on a species. This envelope is the range of temperatures, rainfall and various other climate-related parameters in which a species exists. As global warming affects the Earth, these climatic envelopes will move based on temperature and related changes. The species that lived in that envelope will then have to migrate along with it. This causes changes in biodiversity when species move into new territories occupied by other species. Other species may not be able to migrate due to natural or man-made obstacles, which can result in the extinction of that species. An example of this already occurring can be found in the treeline near Mount Hotham in the Victorian Alps. In 2005, it moved up in altitude by 40 meters as a result of prior recent climate change.
Global Migration
As global warming continues to be a factor in the shifting of climatic envelopes, species will have to be able to keep up with the changes to survive. Species that are not able to do so may see a decrease in population or even extinction as a result. Certain parts of the world are more prone to this. Mexico, for instance, has the highest diversity of reptiles due to its isolated desert habitats. Some of these species, like the desert tortoise, may not be able to keep up with rapidly-changing temperatures. The same is the case with the nyala in Africa or the South African red lark. Canada and Russia are also likely to be hit hardest by global warming-related changes in biodiversity, because many species migrating north will have to compete with man-made barriers.