Reports issued this year by the Intergovermental Panel on Climate Change find greater and growing evidence of a human impact on the global average temperature and climate. According to a summary of one of these reports, however, even if greenhouse gas emissions were held constant at the levels of the year 2000, “a further warming trend would occur in the next two decades at a rate of about 0.1 degree C per decade.”
Of course, emissions have not been held to year 2000 levels, thus the “global warming” train has left the station, and its impacts are already arriving, with more on the way.
A shift to cleaner sources of energy (as all elected officials now appear to favor) may help mitigate warming and climate change in the near and distant future, but according to the IPCC, Colorado (and every other city, state, or nation in the world) will also need to find ways to adapt to a shifting climate that humans began changing on a global scale at least 30 years ago.
In particular, a rethinking may be needed in many of Colorado’s top issues, including management of forest fires, water, immigration, tourism, and more.Water
According to the summary released by the IPCC Working Group II on the likely impacts of global warming and climate change, the projections for North America include:
Warming in western mountains is projected to cause decreased snowpack, more winter flooding, and reduced summer flows, exacerbating competition for over-allocated water resources.
Disturbances from pests, diseases, and fire are projected to have increasing impacts on forest, with an extended period of high fire risk and large increases in area burned.
The IPCC report notes a 90% or greater chance that these projections will become a reality. Such climate shifts will attack Colorado’s economy both at its core and its weakest point – tourism and water.
Winter tourism will be impacted by reduced snowfall. Less snow and an earlier Spring runoff means a shorter ski and snowboard season. Increased pest and fire control problems, along with a shifting climate, will also produce a shift in the location of ideal wildlife habitat. As Colorado warms, then, hunters and anglers will need to find new favorite spots to visit, possibly having to travel to Wyoming.
Further, state water resources will be reduced even more, as the state will likely face longer and more severe droughts. Water storage has long been a lightening rod in state politics, largely as a result of Front Range growth. Now, there will also be less water to fight over, even as Colorado’s farmers will be clamoring for a larger share to help meet growing demand for ethanol.
Fortunately for American farmers, the report notes, “moderate climate change in the early decades is projected to increase aggregate yields of rain-fed agriculture by 5-20%.” Unfortunately for Colorado farmers, the scientists also note, “Major challenges are projected for crops that are near the warm end of their suitable range or depend on highly utilised water resources.”
The recently released IPCC summary also reports about an eight in ten chance that much of Latin America will bear a significant burden:
Climate change is expected to lead to salinisation and desertification of agricultural land. Productivity of some important crops is projected to decrease and livestock productivity to decline, with adverse consequences for food security.
That is, climate change prompted by human emissions of greenhouse gases (24% of which are from the United States) will lead to farmlands in Latin America turning into deserts. Millions of farming families from Latin American who currently live off their land will be forced to find another way to feed themselves. Colorado, then, should expect growing numbers of immigrants from Latin America.
Rising temperatures and shifting weather patterns will also put additional strain on Colorado cities. The same IPCC report also notes a 90% or greater chance that:
Cities that currently experience heat waves are expected to be further challenged by an increased number, intensity, and duration of heat waves during the course of the century, with potential for adverse health impacts. Elderly populations are most at risk.
Higher temperatures and heat waves put greater pressure on Colorado’s electricity grid, which already faces pressures to expand generating capacity without increasing greenhouse gas emissions as a result of population growth.
These projections have generally been called out as reasons to reduce our carbon emissions. According to another report by the IPCC, though, reducing emissions will not prevent the problem. Climate change has begun, and Colorado needs to prepare for the worst as best it can.
Anthropogenic warming and sea level rise would continue for centuries due to the time scales associates with climate processes and feedbacks, even if greenhouse gas concentrations were to be stabilized.
Some of the policy options for adapting to a changing climate are clear: increased water storage and conservation, improved energy conservation, and expanded reliance on man made snow. Other options may require new thinking, such as ensuring new homes have basements, to help reduce energy demand in the summer.