Coastal Ocean Temperatures Reveal Regional Climate Differences
Dust in the West
Reports from the western United States indicate that there’s more dust floating around out there. A team of scientists from the University of Colorado–Boulder (UCB) decided to investigate this increase in dust storms and observations of dust on mountain snowpacks. Using data from the National Atmospheric Deposition Program, the scientists measured the amount of calcium appearing in rainfall. Calcium is deposited into the atmosphere though various sources, like power plant emissions, ocean spray, and the erosion of soil, and is then washed back down in rain. According to UCB professor and study coauthor Jason Neff, the researchers found through the deposits that since 1994 the amount of dust that’s been generated and blown across some parts of the West has “gone up a few hundred percent.” While there likely won’t be another Dust Bowl, more dust does create problems with air quality and faster snowpack melt. Neff noted that his lab hopes to get a better handle on the big picture by using specific dust-measuring instruments installed throughout the region. The study appears in an online issue of the journal Aeolian Research. (SOURCE: The National Science Foundation)
Global open-ocean temperatures are often cited in discussions of the influences of a changing climate, but temperature trends in regional coastal waters have not been widely researched, and thus have received far less attention in the climate change conversation. A new study published in PLoS ONE shifts the focus to this local level with its finding that temperatures in coastal ocean waters have in many cases shifted at much more extreme rates than those in the open ocean over the same time period.
In the study, researchers used sea surface temperatures (SSTs) from a global dataset for the years 1982–2012 to characterize the thermal conditions in coastal waters. By focusing only on the ocean waters adjacent to land on major north–south-oriented continental coastlines, they were able to identify and analyze 11 different coastal latitudinal temperature gradients worldwide; these gradients are believed to have important influences on the marine life that inhabit the different coastal regions. For each gradient and latitude, the researchers determined whether warming occurred and whether seasonal variations became more extreme. They found a significant regional variation in warming and cooling patterns: some coastal areas, such as in the Pacific Ocean off of South America, experienced a cooling trend, while others, such as in the Northwest Pacific and North Atlantic, warmed by as much as 2.67°C—three times the global average—during the study period. Additionally, more than three-quarters of the coastal waters studied exhibited an increasing trend in seasonal temperature differences.
“The world is getting flatter,” notes the study’s lead author, Hannes Baumann of Stony Brook University. “Coastal waters at high latitudes warm much faster than at low latitudes, hence the majority of the world’s coastal temperature gradients are getting shallower. This could cause dramatic reorganization of organisms and ecosystems, from small plankton communities to larger fish populations.”
According to the study, “coastal and continental shelf regions are the most diverse, productive, and economically important parts of the ocean.” Because temperature is such an important influence on marine life, the findings of latitudinal temperature changes suggest a significant impact on ecological shifts, both spatially and temporally. In addition, the study shines a spotlight on the differences between the lesser-known regional effects of climate change and the commonly stated global effects. (Source: Stony Brook University)