The "crisis" of high water levels on the Great Lakes in the mid-1980s was brought on by changes in the primary components of the hydrologic cycle: precipitation and evaporation.
(The "crisis" of high water levels on the Great Lakes in the mid-1980s; was brought; on; by changes in the primary components of the hydrologic cycle)
The "crisis" of high water levels on the Great Lakes in the mid-1980s
was brought
on by changes in the primary components of the hydrologic cycle