Letter to the Editor: February 6, 2013

To the Editor:

Re: Floodwaters threaten city, January 31, 2013

Climate change came to mind after [last] week’s dramatic temperature drop overnight.

However, Voogt’s description of meridional flow in Iain Boekhoff’s “Floodwaters threaten city” made me reconsider my initial reaction. Meridional flow is a natural phenomenon, independent of human impact, as the Sun also has the equator-to-pole meridional flow. According to NASA, the variations in magnetic field are caused by solar meridional flow, and their cyclical pattern suggests the magnetic field is generated from within the Sun.

Another example of natural, “large-scale flow pattern” causing cyclical variations is ENSO. The year 2005 was the warmest over the past century, as reported by NASA. The fishers of the Pacific Northwest coasts were concerned about the local human activities causing global warming, as the surface water of the California Current System was unusually warm and nitrate-rich in 2005, threatening anchovy fisheries.

However, in a study from Geophysical Research Letters, Vol. 33 in 2006, scientists, including Western’s Charles Trick, showed the seeming anomalies in temperature and water qualities were due to the delay in the remote, winds favourable to upwelling as part of the Earth’s natural oscillations, not local activities. Not every variation is climate change.

— Soohyun Ahn
Science III