Climate mitigating energy production

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The US government is calling on the international community to focus more on the impact of climate change on the oceans, amid growing concern over changes affecting corals, shellfish and other marine life.


US government scientists have voiced their concern over recent signals that marine life is under pressure. An enormous toxic algal bloom nicknamed the “blob”, stretching from the Gulf of Alaska to the coast of Mexico, has been linked to the deaths of 30 large whales (Figure 1 right) washed up on Alaskan coasts.


More than 250,000 Pacific salmon have died or are dying, meanwhile, due to warm temperatures in the Columbia river. Scientists predict that up to 80% of the sockeye salmon population, which swim up the river from the ocean to spawn, could ultimately be wiped out.


A study by researchers from the University of British Columbia recently found that global fisheries catches were increasingly dominated by warm-water species as a result of fish migrating towards the poles in response to rising ocean temperatures.


Ian Perry, a research scientist with the Department of Fisheries and Oceans based on Vancouver Island, says butterfish, tope sharks, ocean sunfish, even a finescale triggerfish have all been spotted further north than usual.


 Another UBC study suggests fish are getting smaller as the oceans warm because the warmer water holds less oxygen.


The U.S. National Wildlife Federation warned in advance of the current salmon die-off that a 3oF  rise in average August temperatures would cause up to 20 percent of the streams in the Columbia River Basin and coastal watersheds of Washington and Oregon to become too warm for most salmon, steelhead and trout and that global warming will likely dramatically alter the Pacific Northwest's rivers in which these fish are spawned, hatched and initially or permanently reside. There will be less winter snow accumulation, earlier peak spring stream flows, lower summer stream flows and elevated stream temperatures all of which will be detrimental to the existence of these species. (In fact this would be a universal consequence of global warming.)


Most of these conditions currently exist in the Pacific Northwest as a result of a record low snowpack and as NOAA has determined, the average global temperature for July, 2015 was 1.46°F above the 20th century average.  


As can be seen from the NOAA visual (Figure 2 right), one of the warmest regions is the one in which Pacific Salmon spend most of their lives.


An even greater warming threat to fisheries is the cutting off of their food supply from the nutrients they need to survive by thermal stratification. Phytoplankton are the base of the ocean food chain and the lungs of the planet in that they produce half the oxygen we breath.


The British Royal Society notes, marine phytoplankton biomass and productivity have been shown to decrease in response to temperature-driven stratification that isolates the plants, which require sunlight, from cool, nutrient-rich, deeper, water.


The other threat to marine life stems from the increasing acidity of ocean waters. Near the surface concentrations of carbon dioxide in the atmosphere and the water are in equilibrium. Since the beginning of the Industrial Revolution atmosphericCO2 levels have increased from 280 parts per million (ppm) to 400 ppm.


When CO2 mixes with water it forms Carbonic acid and since the levels of CO2 dissolved in the ocean have been increasing so too has ocean  acidity.


As the Ocean portal of the Smithsonian puts it: Some marine species may be able to adapt to more extreme changes—but many will suffer, and there will likely be extinctions. We can't know this for sure, but during the last great acidification event 55 million years ago, there were mass extinctions in some species including deep sea invertebrates. A more acidic ocean won’t destroy all marine life in the sea, but the rise in seawater acidity of 30 percent that we have already seen is already affecting some ocean organisms.


These threats to marine life are mitigated with energy production that reduces thermal stratification and moves the heat away from the habitat of most aquatic life.






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