Answer:
The mean center of population is the place where an imaginary, flat, weightless, and rigid map of the United States would balance perfectly if all residents were of equal weight. Historically, the movement of the center of population has reflected the expansion of the country, the settling of the frontier, waves of immigration and migration west and south. Since 1790, the center of population has moved steadily westward, angling to the southwest in recent decades.
SOURCE: Geography Division, "Centers of Population Computation for the United States 1950-2010," issued March 2011, available at www.census.gov/geo/www/2010census/centerpop2010/COP2010_documentation.pdf. Consulted for historical reference: Historical Atlas of the United States, National Geographic Society, 1988.
NOTE: The Proclamation Line of 1763 limited British settlement to areas east of the Appalachian Mountains. Alaska and Hawaii were not included in the calculation of the mean center of population until 1950. Puerto Rico was not included in any decade. For more information on the mean center of population, an animated map, and other resources. This graphic is adapted from the "Census Atlas of the United States" published by the Census Bureau in 2007.
Explanation:
Climate change is happening, it is caused in large part by human activity, and it will have many serious and potentially damaging effects in the decades ahead. Greenhouse gas emissions from cars, power plants and other man-made sources—rather than natural variations in climate—are the primary cause. These emissions include carbon dioxide — the main greenhouse gas — which has reached a concentration level in our atmosphere that the Earth hasn’t seen for more than 400,000 years. These greenhouse gases act like a blanket, trapping the sun’s warmth near the earth’s surface, and affecting the planet’s climate system.
Answer:
Water level increase, animals that live on ice caps adapt or die, food chain thrown off etc.
