The Persian Gulf oil spill, once feared bigger than the 4.2 million barrels released by the Ixtoc I blowout in the Gulf of Mexico, is actually much smaller, about 1.5 million to 2 million barrels. That's good news, but the oil that remains is not.
The Gulf of Mexico is open to the Caribbean. Prince William Sound, fouled by millions of gallons of oil spilled from the Exxon Valdez, has huge tides and rapid exchange of waters with the sea. But the Persian Gulf is surrounded by desert, with little inflow from rivers, no glaciers to provide fresh, clear water and little rainfall.
That means the 3,650 animal species, 50 already threatened, face extreme danger from three big oil slicks caused mostly by Iraqi sabotage. Natural cleansing promises little relief. The gulf, 650 miles long and 250 miles wide, narrows to 35 miles at the Strait of Hormuz. At that shallow neck, colder, saltier water remains on the bottom while warmer water rises to the surface. Note that debris from a downed Iranian jetliner in 1988, afloat on the surface, is just now making its way into the Arabian Sea.