Industrial Development in North America Led to Warming of Greenland

by VR Sreeraman on Aug 10 2007 6:01 PM

Industrial development in North America between 1850 and 1950 greatly contributed to increased melting of the glaciers in Greenland, according to a new study appearing online in Science.

Industrial development in North America during those 100 years increased the amount of black carbon - commonly known as soot - that fell on Greenland's glaciers and ice sheets.

The soot impacted the ability of the snow and ice to reflect sunlight, and contributed to increased melting and higher temperatures in the region during those years, the study reported.

For the research, the team led by Joe McConnell and Ross Edwards from the Desert Research Institute (DRI) in Reno, Nevada, captured and analyzed ice core samples from various regions of Greenland.

These samples allowed them to analyze annual deposits of soot and other chemical going back more than two centuries.

Findings revealed that the source of most of the black carbon soot landing in the region changed from natural causes such as forest fires and volcanic eruptions to industrial sources.

The levels of soot deposits as a result of human activity in some years reached as much as eight times than naturally-occurring soot deposits measured in the years before 1850, finally reaching a peak around 1910, the study revealed.

The scientists also found traces of vanillic acid and sulphur, two indicators of forest fire and industrial emissions, respectively, in the samples.

'In addition to black carbon, we measured a broad range of other chemicals at very high depth resolution in this same ice core,' said McConnell.

'When we compare changes in the black carbon to changes in these other indicators, it is clear that most of the increases in black carbon in the late 19th and early 20th centuries, particularly in winter and spring, resulted from industrial emissions - probably from coal burning,' he said.

The team believes these elevated levels of soot decreased the snow and ice pack's ability to reflect sunlight, which allowed the surface to absorb more energy from the Sun.

'These changes may have resulted in earlier snow melt and exposure of darker rocks, soil and sea ice, leading to warming throughout Greenland in the late 19th and early 20th century when soot levels were at their highest,' the researchers wrote in their study.