Since the mid-1970s, large-scale episodic events such as disease epidemics,massmortalities, harmful algal blooms and other population explosions have been occurring in marine environments at an historically unprecedented rate. The variety of organisms involved (host, pathogens and other opportunists) and the absolute number of episodes have also increased during this period. Are these changes coincidental? Between 1972 and 1976, a global climate regime shift took place, and it is manifest most clearly by a change in strength of the North Pacific and North Atlantic pressure systems. Consequences of this regime shift are: (1) prolonged drought conditions in the Sahel region ofAfrica; (2) increased dust supply to the global atmosphere, by a factor of approximately four; (3) increased easterly trade winds across the Atlantic; (4) increased eolian transport of dust to the Atlantic and Caribbean basins; and (5) increased deposition of iron-rich eolian dust to typically iron-poor marine regions. On the basis of well-documented climate and dust observations and the widely accepted increase in marine outbreak rates, this paper proposes that the increased iron supply has altered the micronutrient factors limiting growth of opportunistic organisms and virulence of pathogenicmicrobes, particularly in macronutrient-rich coastal systems.
Mendeley saves you time finding and organizing research
Choose a citation style from the tabs below