Asteroid Affirmative



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UV-B Radiation ! – Ocean Biodiversity




Loss of ocean biodiversity kills all animal and plant life – only microbes will be left

Jackson 8 (Jeremy B. C. Jackson, Center for Marine Biodiversity and Conservation, Scripps Institution of Oceanography, University of California at San Diego, “Ecological extinction and evolutionin the brave new ocean”, PNAS August 12th, 2008 vol 105 no. Supplement 1 11458-11465, available at http://www.pnas.org/content/105/suppl.1/11458.full)

Predicting the future is, at best, a highly uncertain enterprise. Nevertheless, I believe we have a sufficient basic understanding of the ecological processes involved to make meaningful qualitative predictions about what will happen in the oceans if humans fail to restrain their style of exploitation and consumption. Failure to stop overfishing will push increasing numbers of species to the brink of extinction—perhaps irreversibly as for Newfoundland cod—except for small, opportunistic species. Unrestrained runoff of nutrients and toxins, coupled with rising temperatures, will increase the size and abundance of dead zones and toxic blooms that may merge all along the continents. Even farmed seafood will be increasingly toxic and unfit for human consumption unless grown in isolation from the ocean. Outbreaks of disease will increase. Failure to cap and reduce emissions of CO2 and other greenhouse gases will increase ocean temperatures and intensify acidification. Warmer and lighter surface waters will inhibit vertical mixing of the ocean, eventually leading to hypoxia or anoxia below the thermocline as in the Black Sea. Biogeochemical cycles will be perturbed in uncertain ways as they have been in the past (94). Mass extinction of multicellular life will result in profound loss of animal and plant biodiversity, and microbes will reign supreme. These predictions will undoubtedly appear extreme, but it is difficult to imagine how such changes will not come to pass without fundamental changes in human behavior. Moreover, as we have seen, all of these trends have actually been measured to a limited degree in the past few decades. The oceans are becoming warmer and more acidic; eutrophication, hypoxia, and the numbers and sizes of dead zones are increasing in quantity and size; vertical mixing of the open ocean is measurably decreasing; and many of our most valuable fisheries have collapsed and failed to recover. Some may say that it is irresponsible to make such predictions pending further detailed study to be sure of every point. However, we will never be certain about every detail, and it would be irresponsible to remain silent in the face of what we already know.


Ocean Biodiversity ! – Economic Collapse



Oceanic biodiversity is key to the economy

Hourigan 99 (Conserving Ocean Biodiversity: Trends and Challenges”

The Living Ocean Treasure. The ocean’s biological diversity—the living resources that compose it and the ecological processes that sustain it—forms a foundation for the quality of human life as well as the raw materials to enrich it. Biological diversity, or biodiversity, refers to the variety and variability among living organisms, and among the ecological complexes of which they are a part. Marine living resources provide essential economic, environmental, aesthetic, and cultural benefits to humanity. Sixteen percent of all animal protein consumed worldwide comes from the ocean. The United Nations Food and Agriculture Organization (FAO) estimates the total value to fishers of the world’s commercial marine catch at $80 billion per year. The comparable value of fishes landed in the United States is $3.5 billion, and commercial fisheries contribute $21 billion to the U.S. economy. Besides food, marine living resources provide myriad products including fertilizers, animal feed, medicines, and aquarium fishes. The value of marine biodiversity extends far beyond fisheries and other products. Marine ecosystems also provide natural goods and services such as carbon storage, atmospheric gas regulation, nutrient cycling, and waste treatment. Coral reefs, mangroves, and kelp forests protect coastal areas from storm damage. Marine algae contribute nearly 40 percent of global photosynthesis. The values of these marine ecosystem services greatly exceed direct use values, yet they generally are not incorporated into economic or policy calculations. Globally, the value of marine ecosystem services has been estimated at $8.4 trillion per annum for open ocean ecosystems, and $12.6 trillion for coastal ecosystems (Costanza et al. 1997). These services depend on marine biodiversity, even though the processes that underlie this dependence are still unclear. As human populations increase, demands have accelerated for food, products, and services from the ocean, as well as for living and recreational space on its shores. The primary threats to marine biodiversity are fisheries operations (both direct overfishing and indirect fishing impacts—e.g., bycatch of non-target and protected species, habitat destruction by trawls and other gear or techniques, and other ecosystem effects that may accompany fishing activities), chemical pollution and eutrophication, physical alteration of coastal and marine habitats, invasions of exotic species, and ultraviolet-B radiation damage to phytoplankton and zooplankton resulting from stratospheric ozone depletion (NRC 1995). Looming on the horizon is the threat of human-caused climate change with potentially major negative effects on tourism, freshwater supplies, fisheries, and biodiversity. These factors also have been identified by the Parties to the Convention on Biological Diversity2 as key threats (UNEP/CBD 1995).

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