One of my favorite diversions is finding strange words and terms that could have a multiplicity of applications, whatever the actual definition might be.

‘Circumglobal teleconnection’ is one I have just added to my list.

Circumglobal teleconnection (CGT) seems like it could describe anything from a global spirit séance to a single long line of fibre optical cable stretched around the Equator like a sassy belt.

The Earth Wind Map gathers weather data from the Global Forecast System at the National Center for Environmental Prediction, a NOAA initiative. The live interactive map can be accessed here.
Source: Inhabitat.com

The definition of CGT, however, is equally interesting. It is an atmospheric phenomenon involving a narrow, high-altitude wind flow similar to the jet stream. Running on a multiyear cycle, the wind carries moisture from the Gulf of Mexico to the Midwest of the United States at an altitude of approximately 5000 m (16,500 ft).

Or at least, the CGT should run cyclically. Since the 1990s, it seems to have gotten stuck. The CGT is a presumed driver for water levels in the Great Lakes, and since it has lost its rhythm, the water levels in the Great Lakes have been receding.

Warmer winters have also led to increased evaporation on smaller lakes, exacerbating the fall in water levels, which are at their lowest in many decades.

The Great Lakes are a vital source of drinking water for many Canadian and US communities.

Receding water level at Manitoutln Island in Lake Superior. Normal summer water levels would be up to the shore near the tree line.
Photo: GBA / RCI

The interconnected lakes are key routes for shipping and tourism, and the Great Lakes area of 94,250 sq miles (244,106 sq km) comprises 21% of all the world’s surface freshwater, not to mention countless land and water ecosystems.

It’s a complex business, the modelling of climate change, and the circumglobal teleconnection is just one part.

The polar vortex of this winter is expected to push the CGT back into motion, perhaps raising water levels again in the coming years.

Meanwhile, I will be attempting to find ways to work the adaptable term circumglobal teleconnection into everyday conversation.

Early French map of Great Lakes region (1795)
Via: 123rf