Green

Fresh Water Lakes Burning because of Global Warming

Lake Baikal in Russia and Lake Tanganyika in Africa are showing signs of transformation. Scientists have determined depleting levels of oxygen and in effect food chain deterioration and are seriously linking the phenomenon to global warming, and are now looking into the same effect in other freshwater bodies.

In a span of twenty five years, the lakes of the world have revealed a steady increase in temperature, with some rising for as high as 4 degrees Fahrenheit. That’s about seven times quicker than the rise of air temperature. This may not seem like a giant leap, but the slightest change in water temperature can create dramatic consequences such as dying fish, proliferating algae and increasing toxic build-up in the waters. This change may invite non-native species to enter these bodies of water, and they may not be the ones that people want in their waters. For instance, the invasive zebra mussel that is originally from the Great Lakes, are now moving to Lake Superior because it is warmer. This can be a problem, since the proliferation of these mussels could lead to clogged pipes, water motors, and could even kill the species that are native of the lake. Warmer waters also create an opportunity for algal bloom surges. Too much algae is toxic to larger species, particularly fish.

Why do these happen? Warm water contains smaller amounts of oxygen, which is beneficial for algae but not for fish and other lake animals. The heat increases the aquatic animals’ metabolism – they become stressed. Furthermore, warmth also makes toxins like pesticides and metals more toxic.  The studies done related to this phenomenon now aims to determine ecological changes that are happening in these lakes.