OCEAN ACIDITY

OCEAN ACIDITY

Since the industrial revolution, human activities have released hundreds of billions of tons of carbon dioxide (C02) into the Earth’s atmosphere. As oceans warm, their chemistry changes. Seawater becomes more acidic as carbon dioxide in the atmosphere dissolves. Scientists estimate one millions tons of C02 per hour is now invading the oceans creating massive acidity problems and fundamentally changing the balance.

According to Monterey Bay Aquarium, the consequences for life in the sea are only now beginning to be investigated but we know they are catastrophic. One major impact of ocean acidity is that sounds travel further underwater. Scientists studying the problem estimate that the chemistry of the seawater could change significantly by 2050 and that this change would allow sounds to travel up to 70 per cent further underwater.

The amount of background noise in the oceans, combined with increased oil and gas exploration, military sonar and other noises will impact the behaviour and survival of marine mammals. Sounds are used by whales to find food and to communicate. Already human activity has greatly increased the levels and amount of noise in the oceans. Scientists estimate that noise may already be travelling 10 per cent further as a result of the current industrial activities.

According to the studies undertaken, the more acidic the seawater, the less low and mid frequency sound is absorbed. Other recent scientific studies have shown that ocean acidity is rising at a rate of about 100 times faster than at any known time. The effect of increasing ocean acidity to changes in phytoplankton ecosystems that consume and produce carbon dioxide and other organic “greenhouse gases” is currently under investigation.

Just like land plants, phytoplankton convert carbon dioxide and water to carbohydrates and oxygen through photosynthesis. These carbohydrates are then used as fuel by all forms of ocean life.

As the carbon-containing carbohydrates make their way through the food chain, the carbon is effectively ‘locked up’ and kept out of the atmosphere. The world’s oceans absorb more than 25 per cent of carbon dioxide generated by human activity. The carbon can be kept out of circulation for periods ranging from decades to centuries when dead organisms and other organic matter are transferred to the deep ocean by a process known as the biological pump.

Destroying this natural process has the most profound ramifications for all marine life and for life on earth. Ocean acidity is another major threat facing the long term survival of Gray Whales which is not taken into account by National Marine & Fisheries Service