Thermohaline Circulation Wind Feedback

The strength of the wind-driven circulation affects the MOC. In the northern North Atlantic the wind-driven circulation is part of the advection of water northward into the water mass formation areas. Intensification of the low pressure atmospheric system can have several effects: (1) increasing the strength of the subpolar circulation and hence increasing the inflow of lower-latitude waters into convection regions and outflow of lower salinity arctic and subarctic waters to the south, and (2) increasing the heat loss through increased wind speed in the whole subpolar region as well as in the deepest convection regions. The first will reduce surface density throughout the subpolar region, increase density stratification, and could lead to warmer SST where the northward flow is stronger, and colder SST in the low-salinity regions where deep convection is inhibited. The second will increase the propensity for convection and will reduce surface temperatures.

In the Southern Ocean, wind-driven upwelling in and south of the Antarctic Circumpolar Current is an essential part of the MOC. The strength of Southern Hemisphere westerlies can affect the strength of this upwelling and may be the major control on the Southern Hemisphere MOC. Atmospheric warming would not easily disrupt the temperature, although it could affect the net upwelling transport (Toggweiler and Samuels, 1995). A weakened southern polar vortex would be associated with an equatorward shift of the storm track and a reduction in intensity of the cyclonic ocean circulations and upwelling. This might affect the ice edge (reduction in ice cover), which would exacerbate the warming and further weaken the polar vortex. However, because of the deep upwelling the impact of the oceanic portion of this feedback would not be as pronounced as if the upwelling had a much shallower source.

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Renewable Energy 101

Renewable Energy 101

Renewable energy is energy that is generated from sunlight, rain, tides, geothermal heat and wind. These sources are naturally and constantly replenished, which is why they are deemed as renewable. The usage of renewable energy sources is very important when considering the sustainability of the existing energy usage of the world. While there is currently an abundance of non-renewable energy sources, such as nuclear fuels, these energy sources are depleting. In addition to being a non-renewable supply, the non-renewable energy sources release emissions into the air, which has an adverse effect on the environment.

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