Subscribe Now

The AO is the oscillation of pressure difference between the middle and high latitudes in the Northern Hemisphere. Negative phases occur when there is relatively high pressure over the polar regions and low pressure over the mid-latitudes, with positive phases featuring the opposite characteristics. Since the 1970?s, the index has been predominately positive. Positive phases [...]

The El Nino-Southern Oscillation (ENSO), or the cyclical movement of heat in the tropical Pacific Ocean, affects atmospheric phenomena throughout the world. Its effects are the most pronounced during the winter, when the temperature difference between the atmosphere and the oceans is the greatest. The cycle affects the strength and position of the Pacific Jet [...]

The El Ni?o-Southern Oscillation (ENSO), or the cyclical movement of heat in the tropical Pacific Ocean, affects atmospheric phenomena throughout the world. Its effects are the most pronounced during the winter, when the temperature difference between the atmosphere and the oceans is the greatest. The cycle affects the strength and position of the Pacific Jet [...]

The El Nino-Southern Oscillation (ENSO), or the cyclical movement of heat in the tropical Pacific Ocean, affects atmospheric phenomena throughout the world. Its effects are the most pronounced during the winter, when the temperature difference between the atmosphere and the oceans is the greatest. The cycle affects the strength and position of the Pacific Jet [...]

The El Nino-Southern Oscillation (ENSO), or the cyclical movement of heat in the tropical Pacific Ocean, affects atmospheric phenomena throughout the world. Its effects are the most pronounced during the winter, when the temperature difference between the atmosphere and the oceans is the greatest. The cycle affects the strength and position of the Pacific Jet [...]

The El Nino-Southern Oscillation (ENSO), or the cyclical movement of heat in the tropical Pacific Ocean, affects atmospheric phenomena throughout the world. Its effects are the most pronounced during the winter, when the temperature difference between the atmosphere and the oceans is the greatest. The cycle affects the strength and position of the Pacific Jet [...]

Tree Swallows are medium-sized birds with white underbellies and iridescent blue-green capes that run from their heads to their wing tips. They often live in flocks that can number hundreds of thousands of birds and just before sunset, these flocks will swarm around their roosting spots in great circles that resemble living tornadoes. In the [...]

Seabirds, such as auks, gulls, petrels, terns, and gannets, have spent tens of millions of years adapting to life on the ocean. Some species, such as the Sooty Tern, can spend years at sea before returning to land. The success of these species is dependent on the success of their food sources (such as fish [...]

Since the 1930s, when they were accidentally brought by ship to Mobile, Alabama, South American fire ants have been expanding their range and now live as far north as Delaware. Similarly, Argentine ants have recently been introduced to North America and are flourishing in the Southeast. Warming temperatures and increases in rainfall have occured throughout [...]

In the Amazon Rainforest, woody climbing vines, also known as lianas, are increasing in dominance throughout the Amazon Rainforest at a rate of 1.7 to 4.6 percent a year. Lianas harm the trees that they attach to and use as ladders, and are considered parasites. Carbon Dioxide (CO2) levels have risen from 280 parts per [...]

The warming trend over the last thirty years in the Eastern U.S. has coincided with changes in the behavior of migratory birds. Depending on each individual specieslifestyle, birds that breed in the northern U.S. and southern Canada may either delay or advance the date at which they begin their journey south in the fall. Because [...]

Over the last 40 years in the eastern U.S., there has been an increase in the frequency during warm months of 30-day periods when there is no rain. These dry spells now occur about twice as often as they did in the 1960′s. Rainfall events push water through municipal sewer and storm water systems. During [...]

Rice yields must increase by one percent each year in order to meet the world’s growing demand. The United States is the world’s third biggest rice exporter, and rice production in the United States is a 1-1.5 billion dollar a year industry. Louisiana produces close to 3 million pounds of rice a year, and Texas [...]

Growing seasons are defined as the annual period between the last frost, which occurs in the late winter or early spring, and the first frost, which usually occurs in the fall. In the last half of the twentieth century, the length of America’s growing season grew each decade by and average of 2 days. There [...]

Tropical cyclones are one of Earth’s mechanisms for distributing heat from the sweltering tropical regions to the frigid poles. Once the winds inside these cyclones reach 75 miles per hour, they are classified as hurricanes. There are five categories of hurricanes, with category five hurricanes being the most severe. Warm ocean water is necessary to [...]

Since 1910, overall precipitation in the lower 48 states has increased by ten percent, and the region with the largest increase in rainfall is the Mississippi River Basin. Because of fertilizer use on farms, lawns, and gardens in the Basin, wet years mean that more nitrogen (an ingredient in fertilizer) is carried with rainwater into [...]

Prior to European settlement, Longleaf Pine forests covered a 140 million square mile area that runs along the Atlantic and Gulf Coasts from Southern Virginia to Texas. Frequent, low-intensity fires, which traditionally happened every two to four years and would sweep across the forest floor like a broom without killing the Pine trees themselves, keeping [...]

Getting a break from exposure to hot temperatures is important for preventing heat related illnesses. While people usually associate extreme daytime temperatures with heat stroke, if it does not cool sufficiently during the night, the body will not get a break from the heat. In North America over the last 50 years, average nighttime low [...]

Getting a break from exposure to hot temperatures is important for preventing heat related illnesses. While people usually associate extreme daytime temperatures with heat stroke, if it does not cool sufficiently during the night, the body will not get a break from the heat. In North America over the last 50 years, average nighttime low [...]

Coral reefs provide food for billions of people. All of the benefits of coral reefs are being threatened by two trends: increasing ocean temperatures and increasing ocean acidity. Between 1955 and 199, world ocean heat content rose by 0.037 degrees Celsius. While this number may seem small, the same amount of energy it would take [...]