nce in autumn between the southern edge of the pack ice and the coastal areas is increasing with climate change, this distance may become too great for the pregnant females to cross” (Fischbach et al, 2007). Not only polar bears but walruses have also experienced a drastic decrease in population size as a result of increasing sea levels and rising temperatures. As a result of shrinking ice, walruses have lost a major portion of their habitat and thus have also been added to the list of endangered species since 2011. These findings show that there is no “winning” in this situation and these arctic animals are finding very hard not only to reproduce but also just to survive.

Figure 1.3 Shows the effects altering sea ice conditions have on the availability of food for the polar bears. The conditions cause the bear top to spend more energy in trying to find food therefore its weak appearance.

Ocean Acidification

The increased acidification of the ocean as a result of increased CO2 is also another major threat created greenhouse gas emissions, in this case to the biodiversity of aquatic animals. The majority of the CO2 emitted into the atmosphere, is absorbed by the ocean resulting in the decrease of its PH levels. The mechanism by which the PH decreases is explained in the article by the ocean portal team “when CO2 is absorbed by seawater, a series of chemical reactions occur resulting in the increased concentration of hydrogen ions. This increase causes the seawater to become more acidic.” (The Ocean Portal Team, 2018). As the ocean acidifies the carbonate ions, which are important to structures such as shells and corals, become less valuable. It makes it extremely hard for calcifying (shell using) organisms such as oysters, clams and calcareous plankton to build and maintain shells necessary for their protection. As a result of these consequences we may see smaller populations of such animals, which in the long run can relay them to be overexploited by their prey, eliminating them from the ecosystem. Another possibility of could be that the predators themselves cannot detect these animals because of new appearances (no shells), which in turn could prove to be harmful for the predators by reducing their food source. In any case, the food chain of aquatic animals is affected as a result of acidification. This disruption may also affect the people who harvest these fish not only for consumption but for their economies, as they now would have to adapt and find different sources of food and income or migrate, decreasing the biodiversity of the area. “Overall, [acidification] is expected to have dramatic and mostly negative impacts on ocean ecosystems- [even though] some species (especially those that live in estuaries) are finding ways to adapt to the changing conditions.” (The Ocean Portal Team, 2018).