In the long-term forecast …
Less snow in Aspen, more dust in Africa
Predicting long-term climate trends is fraught with imprecision. Climate is complex. Some factors are not fully understood. And the rate of change can be altered by human choices.
Nonetheless, climate projections help people make social and economic decisions. And even when impacts are uncertain, experts recognize a need to prepare. From Colorado resorts to African slums, leaders eye the future climate.
CU Geography Professor and INSTAAR Fellow Mark Williams, for instance, recently co-authored a study of the potential changes in snow and avalanches on Aspen Mountain between 2030 and 2100.
That study, published in the journal Cold Regions Science and Technology, concluded that snowpack will depend partly on the concentration of greenhouse gases.
The low- and mid-range greenhouse-gas scenarios show wet avalanches starting 16 to 27 days earlier than historical averages by 2100. The high-emissions scenario projects that wet avalanches begin 41 to 45 days earlier.
Such differences can be measured in dollars and cents. Ski areas close unstable runs, and closures shrink the bottom line.
In another impact-related study, sociology doctoral candidate John Tribbia and Suzanne Moser of the National Center for Atmospheric Research surveyed coastal managers of California to assess their preparedness for rising sea level.
Writing in the March 4 edition of Environmental Science & Policy, Tribbia and Moser report that coastal managers want to prepare for rising sea level, “but require financial and technical assistance from other agencies at the state and federal level.”
They suggest more cooperation between “science and practice.”
Lori Hunter, an associate professor of sociology and environmental studies, studies human migration caused by environmental hazards. She is starting a study of climate variability, migration and livelihoods in rural South Africa.
In an article published last year by the Population Reference Bureau, Hunter noted that residents of the poorest and least-industrialized nations have emitted comparatively little greenhouse gas but will suffer disproportionately from further climate change.
In many rural regions of developing countries, households depend heavily on local natural resources for food (such as wild vegetables and insects) and also to make products to be sold at market (such as reed baskets and grass brooms).
Shifts in temperature and precipitation can impinge upon local resources and affect livelihoods.
Hunter says governments should enact policies to minimize climate-related livelihood impacts. Such policies may also reduce climate-related human migration, since migration is often a method of seeking alternative means of survival.
Taking such steps, she and others contend, makes sense even in the absence of very reliable projections.
A recently released inventory of the university’s greenhouse-gas emissions detailed the campus’ energy use by sector, more than 66 percent of which is caused by electrical usage. CU’s GHG emissions in 2007-08 were 170,240 metric tons of CO2, roughly equivalent to the emissions of 8,960 U.S. households. CU emits 4.7 metric tons of carbon dioxide equivalent per full-time student. Boise State University emits less per student (3.5 metric tons per full-time student), and many, including the University of Arkansas (at 9.7 metric tons per full-time student) emit more than CU. In the last three years, CU’s GHG emissions have grown by 8.5 percent, a change partly driven by a 10.3-percent increase in gross square footage of campus buildings.
