Jet Stream Warming Meshes the Seasons

A difference of five degrees Fahrenheit may not seem too noticeable of a change in temperature, but to many biological processes on Earth, five degrees Fahrenheit can make or break natural cycles. Global warming, also known as the Greenhouse Effect is one of Earth’s natural processes that occurs as a result of the absorption of heat through gases in the atmosphere. This Greenhouse Effect and the term ‘global warming’ are terms that can be differentiated through the context of usage. The Greenhouse Effect is a necessary process to maintain Earth’s constant average temperature of 57°F (14°C), while when referring to the politically charged term ‘global warming’ the question is raised over the extent of the impact of human activities in influencing global warming, and whether rising average temperatures and melting ice caps are unordinary events. 

Studies show global warming is affecting Earth’s natural processes in a variety of ways. In one such study, data suggests that rising arctic temperatures affect lower-tropospheric temperatures across the earth, and therefore slow the northern jet stream. A jet stream is a tropospheric wind current generally moving westerly between air masses of different temperatures. Winds are created when the temperature differences between air masses are great enough to create a gradient of change. This gradient is largest during the winter months, and therefore the cold air moves more quickly through the troposphere. 

The slowing of the northern jet stream is a result of the decreasing temperatures in Earth’s arctic regions. This slow-down, or narrowing of the gradient of the jet stream, appears to be causing a meshing of seasonal changes. Because the gradient of the jet stream is responsible for the defined change in temperatures that indicate seasonal changes, a lower gradient means less seasonal change. Consequently, the general cold seasons would blend together to one half of the year, while the other extreme would be the hot season. Weekly changes and fluctuations of temperatures may not be seen, resulting in one long-term heat wave or cold spell.

The summer of 2012 can exemplify this theory of the meshing of seasons as the United States is caught in the middle of one of these drawn out heat waves. Throughout the Midwest and Northeast, record high, stagnant temperatures have been recorded.

Global warming is one of Earth’s natural processes, thought to have been occurring since the creation of the planet. The way in which humans are experiencing the effects of global warming is through the decreasing gradient of temperature of the jet streams.