Science Feature
Timeline: The Frightening Future of Earth
Andrea Thompson, and Ker Than
Our planet's prospects for environmental stability are bleaker than ever with yet another Earth Day passing by on April 22. Global warming is widely accepted as a reality by scientists and even by previously doubtful government and industrial leaders. And according to a recent report by the Intergovernmental Panel on Climate Change (IPCC), there is a 90 percent likelihood that humans are contributing to the change.
The international panel of scientists predicts the global average temperature could increase by 2 to 11 degrees Fahrenheit by 2100 and that sea levels could rise by up to 2 feet.
Scientists have even speculated that a slight increase in Earth's rotation rate could result, along with other changes. Glaciers, already receding, will disappear. Epic floods will hit some areas while intense drought will strike others. Humans will face widespread water shortages. Famine and disease will increase. Earth's landscape will transform radically, with a quarter of plants and animals at risk of extinction.
While putting specific dates on these traumatic potential events is challenging, this timeline paints the big picture and details Earth's future based on several recent studies and the longer scientific version of the IPCC report, which was made available to LiveScience.
2007
More of the world's population now lives in cities than in rural areas, changing patterns of land use. The world population surpasses 6.6 billion. (Peter Crane, Royal Botanic Gardens, UK, Science; UN World Urbanization Prospectus: The 2003 Revision; U.S. Census Bureau)
2008
Global oil production peaks sometime between 2008 and 2018, according to a model by one Swedish physicist. Others say this turning point, known as "Hubbert's Peak," won't occur until after 2020. Once Hubbert's Peak is reached, global oil production will begin an irreversible decline, possibly triggering a global recession, food shortages and conflict between nations over dwindling oil supplies. (doctoral dissertation of Frederik Robelius, University of Uppsala, Sweden; report by Robert Hirsch of the Science Applications International Corporation)
2020
Flash floods will very likely increase across all parts of Europe. (IPCC) Less rainfall could reduce agriculture yields by up to 50 percent in some parts of the world. (IPCC)
World population will reach 7.6 billion people. (U.S. Census Bureau)
2030
Diarrhea-related diseases will likely increase by up to 5 percent in low-income parts of the world. (IPCC)
Up to 18 percent of the world's coral reefs will likely be lost as a result of climate change and other environmental stresses. In Asian coastal waters, the coral loss could reach 30 percent. (IPCC)
World population will reach 8.3 billion people. (U.S. Census Bureau)
Warming temperatures will cause temperate glaciers on equatorial mountains in Africa to disappear. (Richard Taylor, University College London, Geophysical Research Letters:)
In developing countries, the urban population will more than double to about 4 billion people, packing more people onto a given city's land area. The urban populations of developed countries may also increase by as much as 20 percent. (World Bank: The Dynamics of Global Urban Expansion)
2040
The Arctic Sea could be ice-free in the summer, and winter ice depth may shrink drastically. Other scientists say the region will still have summer ice up to 2060 and 2105. (Marika Holland, NCAR, Geophysical Research Letters)
2050
Small alpine glaciers will very likely disappear completely, and large glaciers will shrink by 30 to 70 percent. Austrian scientist Roland Psenner of the University of Innsbruck says this is a conservative estimate, and the small alpine glaciers could be gone as soon as 2037. (IPCC)
In Australia, there will likely be an additional 3,200 to 5,200 heat-related deaths per year. The hardest hit will be people over the age of 65. An extra 500 to 1,000 people will die of heat-related deaths in New York City per year. In the United Kingdom, the opposite will occur, and cold-related deaths will outpace heat-related ones. (IPCC)
World population reaches 9.4 billion people. (U.S. Census Bureau)
Crop yields could increase by up to 20 percent in East and Southeast Asia, while decreasing by up to 30 percent in Central and South Asia. Similar shifts in crop yields could occur on other continents. (IPCC)
As biodiversity hotspots are more threatened, a quarter of the world's plant and vertebrate animal species could face extinction.
(Jay Malcolm, University of Toronto, Conservation Biology)
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