Does anyone know of a few countries where fish is the staple diet? Are rising sea temperatures harming them?

Question

I'm doing an essay on climate change, and was wondering if anyone could give me some more scientific detail on how rising sea temperatures are harming fish. Is it because the warmer water can dissole less oxygen, and therefore the fish cannot get enough? Also, is this having an effect on countries where fish is the staple diet? I'm researching myslef, but extra info from here will really help. Thanks!

Answer 1

Japan is without doubt the worlds biggest offender of the oceons.

Answer 2

Pretty much all the Asian Countries fish is the main staple in the diets,

Answer 3

Well those countries are just going to have to farm raise fish or soon they will be fishing in the middle of the ocean because fish migrate to find cooler water. There already having problems with migrating tuna fish.

Answer 4

The accumulation of carbon in the oceans as a result of more than a century of fossil-fuel use and deforestation has increased the acidity of the surface waters, with serious consequences for corals and other marine organisms that build their skeletons and shells from calcium carbonate.

Coral reefs are critical to much of the ocean's productivity (providing critical spawning and feeding grounds), so given that many ocean species are overfished already we're playing with fire with one of our fundamental food sources.

Studies link carbon dioxide and methane to past climate changes that have caused the extinction of over 95% marine species at the time:

Climate Model Links Warmer Temperatures to Permian Extinction

http://www.physorg.com/news6003.html

"The CCSM indicated that ocean temperatures warmed significantly at higher latitudes because of rising atmospheric levels of carbon dioxide, a greenhouse gas. The warmer temperatures reached a depth of about 10,000 feet (4,000 meters), interfering with the normal circulation process in which colder surface water descends, taking oxygen and nutrients deep into the ocean.

As a result, ocean waters became stratified with little oxygen, proving deadly to marine life. Because marine organisms were no longer removing carbon dioxide from the atmosphere, that, in turn, accelerated warming temperatures.

"The implication of our study is that elevated [carbon dioxide] is sufficient to lead to inhospitable conditions for marine life and excessively high temperatures over land would contribute to the demise of terrestrial life," the authors conclude.

We can see that this happened in the past due to elevated carbon levels.  All indications are that we're doing an effective job at accelerating the global climate towards that "dead zone" state at a record rate.

Answer 5

Since CO2 is the critical limiting factor in the rate of photosynthesis, an increase of concentration in the oceans will be of benefit to the phytoplankton which form the base of the food chain. The huge volume of water in the world's oceans (70% of the surface, average depth 4KM) act as a buffer against  acidification, so there has been no measurable change in ocean pH since records have been kept.

Answer 6

With the price of food going up none will be eating fish . Research is being done to turn old tires into food .

Answer 7

Cold water holds more nitrogen, oxygen and supports vast quantities of phytoplankton and zooplankton (one reason why northern seas are murky is that the murk is caused by the huge numbers of this microscopic life, tropical seas are so clear because they contain very little life, 90% is accounted for by coral reefs and the fish that have adapted to live off this ecosystem.) which are be basis of the marine food chain.

The worlds richest fishing areas are in areas where cold water rises (upwells) from the depths to the surface bringing fish up with it. This usually happens along coasts where cold, deep currents meet undersea continental shelf’s forcing them to rise.

Many fish are very sensitive to changes in temperature, Cod prefer cold waters, the North Sea has warmed 1 degree C in the past decade and the Cod have moved north to colder waters.

Another species that has also followed colder waters north are sand eels, fish that feed of them have also migrated following their food source with repercussions throughout the food chain, particularly on seabird life.

However fish that aren’t so temperature sensitive still remain in the N Sea for the time being and more southern species are being seen more frequently.

Oceans are also major sinks of CO2, if more is in the atmosphere then more has to be absorbed by the seas making them more carbolic or acidic. This again affects microscopic sea life that forms the base of the food chain. Much of their skeletal structures are made from calcium carbonate and becomes prone to dissolution in more acidic waters.

http://www.grist.org/news/maindish/2005/...

http://news.bbc.co.uk/nolpda/ukfs_news/h...

http://www.guardian.co.uk/environment/19...

For more info try ‘Googling’ for different terms in Google News etc.

Answer 8

Global warming's impacts on fishing are speculative at this point.   Most scientists think they will occur (details below) but they haven't been clearly seen yet.

This lays out how global warming could affect fishing in the future.  

http://www.southcoasttoday.com/apps/pbcs...

As noted above, this area is debatable, and something like coral reef impacts (which are being widely seen) might be better.  Basically the coral reefs are far more sensitive to global warming, fish can swim away, for the most part.

Note also that our advanced civilization is more like the coral reefs.  We're not nomads, who can fold our tents and move.