The Next 200 Years: A Scenario For America And ...
Over the next century, it is expected that sea ice will continue to decline, glaciers will continue to shrink, snow cover will continue to decrease, and permafrost will continue to thaw. Potential changes to ice, snow, and permafrost are described below.These maps show projected losses of sea ice in the Arctic and Antarctica. The maps in a) show the average ice concentration (the relative area covered by sea ice) from 1986-2005. The maps in b) and c) show climate model simulations of sea ice thickness in February and September near the end of the 21st century under low (b) and high (c) emission scenarios. In the Arctic, February is projected to have less ice (more blue); September is projected to be nearly ice-free (almost all blue). The projected changes in Antarctic sea ice are more subtle. Source: IPCC, 2013Click the image to view a larger version.
The next 200 years: a scenario for America and ...
For the next three trends, we model both a trendline scenario and a step-up scenario that assumes additional investments in some areas, based on explicit choices by governments, business leaders, and individuals to create additional jobs.
We estimate that between 400 million and 800 million individuals could be displaced by automation and need to find new jobs by 2030 around the world, based on our midpoint and earliest (that is, the most rapid) automation adoption scenarios. New jobs will be available, based on our scenarios of future labor demand and the net impact of automation, as described in the next section.
The USGS and its partners developed the HayWired scenario as a tool to enable further actions such as seismic upgrades and retrofits that can change the outcome when the next major earthquake strikes.
The next major earthquake to strike the San Francisco Bay Area will most likely result from rupture of the Hayward or Rodgers Creek faults. New models show that these faults are directly connected at the surface, which enables simultaneous rupture of the Hayward and Rodgers Creek faults, a scenario that could result in a major earthquake.
We examine these effects under two plausible scenarios: a moderate emissions scenario, where global greenhouse gas emissions rise by roughly 1 percent annually over the next 20 years; and a high emissions scenario, where emissions rise by 3 percent annually. These scenarios are drawn from an extensive literature and correspond with climate scenarios known as Representative Concentration Pathways (RCP) 4.5 and 8.5. We apply similar scenarios for future sea level rise. For details on these scenarios, and our rationale for selecting them, please see the Appendix.
Summer temperatures in Florida have increased by roughly 1F since 1950, averaging 81.4F from 1991 to 2010. In the next 20 years, average summer temperatures are projected to rise above 83F under both moderate and high emissions scenarios.[1,2] There is more uncertainty surrounding future temperatures under a high emissions scenario than under a moderate emissions scenario.
From 1950 to 1970, winter temperatures in Florida averaged 57.4F. In the following decades, temperatures rose by more than 2F, averaging 59.5F between 1991 and 2010. In the next 20 years, average winter temperatures are projected to rise above 60F under both moderate and high emissions scenarios. [1,2] 041b061a72