The ecological consequences of global climate change are expected to be drastic although not much is known as to how individual species will react to these changes.
Irrespective of the causes of climate change, whether anthropogenic or natural, it is imperative that we address these concerns, as they will have widespread impacts on the human species, both directly and indirectly through forcings on other species. The climate is not expected to shift evenly and the ways in which certain species adapt or migrate due to these changes could be erratic and unpredictable. The rate at which the earths climate is currently changing is unprecedented and has not been seen in the past 450,000 years. Although many species have simply migrated northward or vertically up mountainsides to escape warming habitats, others do not have this luxury or cannot migrate fast enough to survive. The earths temperature has risen by over one degree Fahrenheit over the past century, based on land and sea level measurements.
The temperature is expected to continue rising at a faster pace over the next century, possibly increasing by as much as seven degrees Celsius. In comparison, the earths average global temperature was only twelve degrees cooler than it is now during the last great ice age. A vast majority of species now living do so within a narrow spectrum of temperature ranges and will not be able to adapt to a warming climate on such a large scale. If humans are the cause of a warming climate we will ultimately be responsible for the destruction of millions of species.
Polar bears are one species that are currently feeling the effects of a warming climate. Over the past twenty years, NASA satellite data has shown a 2. 9 percent decline per decade in Arctic sea ice, resulting in shorter feeding seasons for polar bears. The species main food source, ringed seals, which live on the ice of Hudson Bay are becoming increasingly inaccessible due to earlier ice melts. “We’re wrong if we think that climate change is something that will happen far off in the future. Polar bears are starving now and we need to act now to stop climate change,” said Kevin Jardine, Greenpeace climate impacts specialist.
A recent study by Canadian polar bear researchers showed that the species have less time to hunt during the season and are forced to return to land undernourished. The study reports a decline in weight of both male and female bears as well as a noticeable decline in offspring. As the Hudson Bay bears fast for six to eight months out of the year, sustaining themselves on nourishment from the hunting season, they are increasingly unable to survive the rest of the year due to limited food resources. Polar bears are not the only species currently under stress form a warming climate however.
Masses of orange-and-black Monarch butterflies that travel on a 3,000-mile annual migration from the United States and Canada covered an area of 42 acres two years ago. Now, however, the butterflies that winter in the area cover a mere 13. 5 acres. Monarch butterflies are very sensitive to climate change; the smallest temperature change can have drastic impacts on their populations.
Monarchs have developed various adaptations in order to avoid being caught and eaten by predators. These adaptations range from their colorful wings to chemical secretions used to repel predators. Many of these adaptations are ineffective in areas outside of their native habitat however and as the species is forced to migrate to more suitable areas, they are forced to further adapt to their new surroundings. At the rate at which the climate is warming, they simply cannot make these phenotypical and morphological changes fast enough and eventually perish.
Numbers of Monarch butterflies are currently declining in North America in trends that concur with what climate models predict. Agriculture and plant species will also be greatly impacted by global climate change. The biggest concern for plants is that they cannot just get up and move. Based on current computer models depicting future trends in climate change, many plant species in the northern hemisphere, mainly Russia and Canada, would have to migrate by up to one kilometer per year, a .
