Because humankind is a narcissistic species, our focus, when considering the implications of global warming, usually is fixed on the third of the planet that comprises dry land. While the land warms, the other two-thirds of the Earth will be warming as well, with profound implications for the species which inhabit it, including a holocaust for coral reefs which already has begun.
According to Peter G. Brewer and associates, writing in Science, the chemistry of ocean water already is being changed by human-induced greenhouse gases in the atmosphere: “The invading wave of atmospheric CO2 has already altered the chemistry of surface seawater worldwide, and over much of the ocean, this tracer field has now permeated to a depth of more than one kilometer” (Brewer et al. 1999, 943). Given that the ocean is slowly warming, as its carbon dioxide level rises, its capacity as a carbon sink is probably being compromised.
Ken Caldeira and Philip B. Duffy assert in Science that “uptake,” or removal, of human-induced carbon dioxide by the oceans is less than many earlier investigators have assumed and that, as temperatures warm, carbon uptake will diminish further. Additionally, Caldeira and Duffy contend that absorption of carbon into the oceans of the Southern Hemisphere (the focus of their study) has been diminishing since 1880 when fossil-fuel effluvia became a factor in the composition of the atmosphere. “Ventilation of the deep Southern Ocean was much more vigorous in the period from about 1350 to 1880 than in the recent past” (Caldeira and Duffy 2000, 620).
Among the important results of warming seas will be coastal erosion, shoreline inundation because of higher tide levels, higher storm surges, and saltwater intrusion into coastal estuaries and groundwater supplies. A report by the World Wildlife Fund said: “Scientific evidence strongly suggests that global climate change already is affecting a broad spectrum of marine species and ecosystems,