We derive our primary estimate of the temperature of the deep earth from the melting behavior of iron at ultrahigh pressures. We know that the earth's core depths from 2,886 kilometers to the center at 6,371 kilometers (1,794 to 3,960 miles), is predominantly iron, with some contaminants.
Greater Cleveland-Akron ranks 16th for population, largest metro area in Ohio. CLEVELAND, Ohio - Although the eight-county Cleveland-Akron metro area lost an estimated 54,000 people from 2000 through 2009, it is still the largest metro area in Ohio, and the 16th largest nationally. Here are the biggest combined metropolitan areas in Ohio, along with their national ranks and populations. 16: Cleveland/Akron/Elyria, 2,891,988
Chicago is the largest city in the region, followed by Detroit and Indianapolis. Some other important cities in the region are: Minneapolis-St. Paul, Cleveland, St. Louis, Kansas City, Milwaukee, Cincinnati, Columbus, Wichita, Des Moines, Madison and Omaha.