Human-caused climate change is already having an impact here in B.C. In the last few years we have experienced:
- higher average air and water temperatures, including record high temperatures in the Fraser River, contributing to a significant decline in salmon survival
- changing patterns of precipitation
- extreme or unusual weather events, such as the high winds that caused major losses of trees in Stanley Park and on southern Vancouver Island
- significant decline in average snowpack, which means less water in the rivers and streams that returning salmon depend on
One of the most serious impacts of the climate crisis for coastal regions like ours is sea level rise, caused by thermal expansion of ocean waters and melting of glaciers and ice fields.
By burning fossil fuels, we are changing the chemistry of the ocean – making it deadly for many of the creatures that live in it.
Up to a third of all the CO2 we release into the atmosphere is absorbed by the ocean. As it dissolves, it produces carbonic acid, which makes seawater acidic.
The more greenhouse gases we produce – from our cars, factories, furnaces, airplanes and power plants – the more acidic the oceans will become.
Ocean acidity is rising dangerously fast. Since the beginning of the industrial age (just 250 years ago), it has increased by about 30% worldwide. It is now rising faster than any time in the past 55 million years – much faster than we can expect plants or animals to adapt.
In an acidic ocean, certain animals will thrive: for example, jellyfish, some seaweeds, and the disease-causing Vibrio bacteria.
But survival will be much, much harder for animals with shells (which includes coral reefs, home to 25% of the world’s marine species).
As acidity increases, animals with shells will grow more slowly and their shells will be weakened. Once the acidity level is high, seawater will dissolve the shells of living animals.
Scientists say that if we continue producing CO2 at our current rate, the ocean’s acidity will more than double – some say it will triple – by the end of this century. Seawater this corrosive will cause immense damage to marine life.