The year 1999 brought killer landslides to Venezuela and Mexico, devastating earthquakes to Turkey and Taiwan, and massive floods and coastal storm erosion along the East Coast of the United States that took lives, displaced families, disrupted communities and impacted economies. The cost of natural disasters, both in human and financial terms, has risen dramatically and may continue to skyrocket in the 21st century, as the world's population grows and moves into areas that are more vulnerable to earthquakes, hurricanes, tsunamis, landslides, floods and other natural hazards. The work by USGS scientists helps understand how and where these natural events occur, so people can build and live safely on the Earth. The real-time information about floods, earthquakes and other hazards provided by the USGS helps people respond quickly and effectively when disaster strikes and provides important scientific data used by decision makers for planning and developing new policies. With the population of the United States projected to increase nearly 60 percent in the next 50 years and an increasing percentage of the nation's population moving to urban areas, society is just beginning to experience the challenges associated with the sustainable growth and development of urban regions.
Diseases become more easily transmissible in and between the two populations.
Some diseases, such as Lyme disease, West Nile virus, plague, hantavirus and rabies are transmitted directly or indirectly to humans by wildlife. This information helps health professionals identify which geographic areas are potentially threatened, to determine which populations are at risk now and in the future, and to more accurately predict when an outbreak might occur and understand how it can be controlled. Biological Invaders Invasive species, such as zebra mussels, fire ants and cheatgrass, are those plants and animals that have been introduced into habitats where they are not native. The planet is changing. Records show sea levels are rising at accelerated rates and levels of carbon dioxide have increased worldwide.