By Neva Knott
I teach at a small college in Washington, Centralia College. Even though we only have 2,600 students, the college has a strong STEM focus. As an extension of the Science, Technology, Engineering, and Math programs, the college hosts speakers for the Rising Tide Seminar Series. The speaker for the January 2015 seminar was Dr. Christopher Sabine, Oceanographer and the Pacific Marine Environmental Laboratory of NOAA. He opened his presentation at Centralia College with the message that climate change is undeniable and serious, but it’s not too late.
Dr. Sabine gave the following five take-home points:
1. The profound impact of humans on the earth’s climate is “unmistakable at this point”
2. Carbon dioxide released into the climate has fundamentally changed the chemistry of oceans
3. The current amount of carbon dioxide in the atmosphere will impact climate for thousands, if not 10’s of thousands, of years
4. Even though the rate of carbon dioxide in the atmosphere has been higher in the past, the rate of increase is 10-100 times faster than ever before in the geological past; this rapid rate of increase has a real, negative impact on adaptation–the ability of species, including humans, to change enough to exist in the changed biotic system
5. That there is a way out
Dr. Sabine’s presentation was largely based on the International Panel of Climate Change Fifth Assessment Report (2013), on which he consulted. The latest findings are that the evidence substantiates a better than 95 percent likelihood of human influence as the driver of climate change. In referencing the work of IPCC, Sabine explained that there are “multiple lines of evidence” to support the unequivocal warming of the earth’s climate system, evidence that he suggested climate deniers can no longer avoid. These lines of evidence are: increasing air temperature; increasing atmospheric water vapor; increasing temperature over oceans; increasing sea temperature; increasing sea level; increasing ocean heat; decreasing sea ice.
The statistics behind these factors are staggering and somewhat unfathomable. Dr. Sabine explained that, as the climate has warmed in the last 40 years, 275 zeda jewels of additional solar energy have accumulated in the earth’s system. To illustrate–one zeda jewel is enough energy for the needs of the entire human population for two years. About seven percent of this accumulated energy is stored terrestrially, on land, in plants and soils. The rest is going into the oceans.
Carbon emissions into the atmosphere are measured in parts per million (ppm). Pre-industrial revolution the atmosphere measured 228 ppm of carbon dioxide, whereas today the measurement is 400 ppm or more.
Dr. Sabine illustrated the increase in atmospheric carbon dioxide with another measurement, the petagram. The current rate of release is right around 10 petagrams per year. The image Sabine offered in order for the audience to wrap our minds around this huge number was this: a 156,500 mile-long hopper car of coal would release one petagram. Thus, the current 10 petagrams would equal that hopper car of coal circling 70 times around the earth at the equator. To further illustrate, Sabine explained that the annual rate of 28,000 square miles of deforestation equals one petagram of carbon dioxide emission.
The culminating effect of the increase in carbon dioxide in the oceans is that the oceanic carbon cycle has been reversed. Pre-industrial revolution and climate change, oceans were a carbon source. Through their natural processes, they released carbon into the atmosphere that was, in turn, taken up by leaves, which then degraded into the soil system, where the carbon was stored. Now, oceans are a carbon sink. This increase is the cause of ocean acidification–because carbon dioxide is an acid gas. Dr. Sabine stated that pH balance is “very important for ocean ecosystems.”
Corals of The Great Barrier Reef. Courtesy of wiki commons.
Acidification makes it difficult for organisms to form shells, using reefs to weaken and bleach.
In the arctic, shells are dissolving off snails. The Great Barrier Reef has lost 50 percent of its coral over the last three decades. Not only is ocean acidification problematic to marine species, one billion people globally rely on the oceans as a food source, some for 100 percent of their dietary protein.
NOAA has several programs to help coastal communities mitigate the effects of climate change. One of the organization’s goals is to create a “climate literate” public. In addition to these public support programs, NOAA offers a Climate Stewards Education Project. NOAA’s efforts are also linked with President Obama’s Climate Action Plan. The solution to ocean acidification is at once simple and enormous–humans must decrease carbon emissions. The time is now.