A recent study released in Science will add a new chapter to the ongoing climate change debate. The study tracks global temperature trends going back 11,300 years, adding roughly five millennia to current global climate records and painting a picture of a planet that has experienced wide fluctuations in global temperature.
According to the study, global temperatures have fluctuated from periods of relative cool — such as the Little Ice Age of the 18th century — to more tropical periods, when Greenland more than lived up to its name. In fact, for a full one-fifth of the time over the past 11,300 years, average global temperatures were warmer than they are today. The difference, argues lead researcher Shaun Marcott, between natural climate change and what we see today is a matter of pace and direction. If climate were determined solely by factors such as solar output, the planet should still be reeling from a period of cooling. Furthermore, global temperatures have increased more in the past 100 years than they have in the previous six or seven thousand.
Despite these qualifications, the findings can be interpreted to support a view of climate change that is increasingly popular in Republican circles, a view which holds global warming to be part of the planet’s natural climate cycles. If the planet has experienced warmer temperatures than what we’re headed towards, then all of the apocalyptic talk of mass extinctions and crop failures must be nothing more than liberal exaggeration. Right?
If projected temperature increases were spread over the next 10,000 years, then Tim Pawlenty and others like him might have some room for comfort. Unfortunately, the current pace of climate change is unprecedented in Marcott’s data, outpacing anything that’s occurred in the past 12,000 years. The six or seven millennia that climate change has historically afforded ecosystems to change and adapt is being narrowed to the next few decades, and, if life on earth is to continue in any recognizable way, we are going to have to step in and take up some of the slack.
Man’s response to climate change can generally fit into two categories: adaptation and mitigation. The latter attempts to reduce the effects of climate change by cutting back on global CO2 emissions. The former seeks to find ways of protecting people and ecosystems from the inevitable.
As of now, mitigation is far likelier to make headlines, from recent Cap-and-Trade programs in liberal states to the international community’s glacial attempts at coordination. Attempts by the Obama administration to increase fuel economy standards are projected to cut billions of metric tons in CO2 emissions. New construction practices reduce energy consumption by 50%. However, global economic growth — the main driver of emissions — will continue to outpace the planet’s ability to absorb carbon emissions. Reducing CO2 can slow down the pace of climate change, but the global economy would have to cease all carbon emissions today if it hoped to keep CO2 at stable atmospheric levels. Since CO2 can stay in the atmosphere for up to 1,000 years, the global economy would have to hold its breath for some time.
That's why the onus is increasingly shifting to adaptation as a strategy for dealing with climate change. Higher global temperatures will force sectors ranging from agriculture to construction into adopting more efficient practices, from drip irrigation to a better, longer-lasting light bulb. Fortunately, many of these measures, from better public transportation and greener cities, have the potential to improve quality of life in today’s traffic-congested, heat-battered cities. Climate change may prove to be irreversible, but not, we hope, without its own silver lining.