Tag Archives: Climate Change

Are we headed towards extinction?

Is it true? Although it is highly debated, our current understanding of science shows that we are facing the next  mass extinction event of the Earth. Many palaeontologists agree that the dinosaurs went extinct at the end of the Cretaceous period 65 million years ago. This mass extinction event called the Cretaceous-Tertiary (KT) Extinction wiped out more than 50% of all species on the planet.

The KT Extinction was caused by a giant asteroid of diameter greater than 10km  that hit the Yuccatan Peninsula of Mexico 65 million years ago, leaving the Chicxulub Impact Crator of more than 180 km in diameter! Initially, this impact vaporized everything close to its vicinity instantaneously, and created an enormous tsunami. A dense cloud formed of debris from the impact created a series of long term effects.  One of which was a global acidic rain phenomenon killing many plants on the surface of the land and causing over 80% of the  marine species.

The KT Extinction was the last mass extinction the Earth has had, but there had been four others beforehand: Late Ordovician, Late Denovian, Late Permian, and Late Triassic. It has been suggested that we are heading towards the 6th mass extinction with our current rate of species going extinct (for example, the Dodo bird, and the Marsupial wolf). Extinction of different types of species on our planet suggest that a smaller variance of creatures will have the ability to survive the next type of mass extinction event whether it be a flood, giant meteor or global climate change.

Marsupial Wolf

Dodo Birds From Ice Age!

In 1984, D. Raup and J. J. Sepkoski analyzed the number of asteroid extinctions during the history of Earth and concluded that there was a mass extinction event every 25 million years. This landmark paper has been cited in over 400 scholarly sources and has led the start of many theories of possible mass extinction scenarios.

So if Raup and Sepkoski’s prediction is true, and our human race faces the next mass extinction event, will we be able to survive?



Less and Less Baby Polar Bears with Melting Arctic Ice

We all know of the strong correlation between changes in the environment and the polar bears,but a recent study suggests that the population of this species, Ursus maritimus, could be in real danger with the decline of Arctic sea ice specifically in our country’s Hudson Bay.

Source: Flickr

Article published on February 8th, 2011 in Nature Communications outlines a study conducted by Peter K. Molnar et al. from the University of Alberta who used mechanistic models to predict changes in litter size of cub polar bears for pregnant females in the western Hudson Bay population under expected changes in sea ice.

Sea ice is vital for the polar bears because during the winter feeding season they rely on the solid floes to take them near the waters where there are lots of food source – seals. But with temperatures rising and early breakup of the ice sheets, the bears are forced ashore sooner than in the past. Moreover, “on shore, there is no food available for them,” as the lead author of the study puts it. Thus the bears, particularly females of reproductive age, are storing up less energy for the months that they have to hibernate during pregnancy.

The researchers found that ~28% of pregnant females already failed to reproduce for energetic reasons during the 1990s. Using mechanistic models, they predicted that if spring sea ice break-up happens 1 month earlier than during the 1990s – 40-73% of pregnant female polar bears could fail to reproduce, and if the break-up happens 2 month earlier55-100% could fail. On a global perspective, the study states that a similar litter size decline trend may be found in over 1/3 of the polar bear population.

What’s even more discouraging is that “the litter size predictions provided in this study serve as another indicator that the western Hudson Bay population will probably not remain viable under predicted climatic conditions” as the article states.

Heart wenching video that hits home of malnourished  mother polar bear and starving cubs as an example of the conditions that polar bears are and will be facing in the future with current climate change conditions. A Warming Climate Takes its Toll on the Polar Bears of Hudson Bay by Daniel J. Cox


Corals Are Moving North

Flickr: Martin-Klein

As the average temperature of the Earth rises due to climate change, the temperature of the oceans rises as well. These drastic rise in ocean temperatures, affect marine organisms of all shapes and sizes. However, the most prominent effects have been observed on corals. Corals, which are home to thousands of marine creatures, are considered to be some of the most fascinating and eye pleasing marine organisms in the oceans. Unfortunately, they are also highly sensitive to environmental changes.

In a recent article published in Science News (which can be found here), coral migration was studied and tracked by a group of scientists off the coasts of Japan. When they compared current results to data collected from different time periods starting in the 1930’s, they found out that various common coral species have retreated northward, and some have even gone as far as temperate waters. Furthermore, the abundance of coral has decreased proportionately with northward migration.

Mila Zinkova/Wikimedia Commons

If this trend were to continue and not be altered, the population of corals in the oceans will continue to decline. This decline is very unfortunate and it shows how deadly climate change can be. Corals are home to thousands of different marine organisms. Hence, the lost of corals, also causes the direct loss of other marine organisms. Ultimately this can lead to an overall reduction in biodiversity. Furthermore, the decline in coral also jeopardizes recreational activities such as scuba diving and snorkeling.

Although this article, provides excellent evidence to support the fact that corals are moving north and their abundance is decreasing. It does not provide us with ways to prevent or slow down this process. Most of us are already aware of the drastic effects climate change has on marine organisms, but very few of us know how to directly prevent such events from occurring. Hopefully we’ll see more media coverage on prevention methods in the future, so that such events can be prevented or subdued in the future.