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Glaciers have a mass balance. Glaciers lose mass by melting during the warm season (primarily the summer months) and gain mass by accumulating snow during the cold season (centered around the winter months). If a glacier accumulates more mass during the cold season than it loses during the warm season, it is said to have [...]

The energy moving in both weather systems and through the wires that power your home can be measured in watts. The Sun heats the Earth causing the fluids of the atmosphere and the oceans to move, creating the winds and currents of Earth’s climate. The vast majority of the energy in the climate system moves [...]

Snow is both a product of the weather and a weather maker. It has long been recognized that snow exhibits a cooling effect on local and regional scales. Snow reflects more sunlight than bare ground, meaning that it absorbs less energy. More snow cover also means soils stay moist for longer following the spring melting [...]

Snowfall and snow cover have direct effects on transportation, soil freeze/thaw cycles, water availability, flood frequency, water quality, wildlife, forest fires and more.
Far from being just a passive product of prevailing climatic conditions, snow cover also influences climate by changing the surface albedo, the amount of solar radiation a surface reflects. The presence of snow, [...]

When put in 2000 US dollars, freezing rain (ice storm) events in America caused an estimated 16.3 billion dollars in total losses between 1949 and 2000 due to downed power lines, downed trees, agricultural losses, transportation accidents and medical costs from injuries due to slippery conditions. Freezing rain events are most frequent in the Northeast, [...]

Ice masses maintain their own local climate through several mechanisms. One mechanism is known as the ice-albedo feedback mechanism: ice is more reflective than surrounding rock or ocean and the more reflective a surface is, the less sunlight it absorbs and the less it warms. Highly reflective ice surfaces promote the cold conditions that allow [...]

Beneath the Antarctic ice sheet lie some of Earth’s final frontiers – networks of subglacial lakes, many of which have been isolated from the atmosphere for as long as 15 million years. Outlet channels allow these lakes to periodically drain into the ocean, refill and drain again. The largest of these lakes, Lake Vostok, lies [...]

Much attention has been given to the decline of sea ice over the North Pole, which fell to a September minimum of 1.6 million square miles in 2007, about 40 percent below normal levels. On the other side of the world, the sea ice that extends from Antarctica’s continental ice sheets out over the ocean [...]

Once water is evaporated from the ocean or a moist land surface, it may spend days traveling through the air. Complicated systems of winds at different levels of the atmosphere can transport moisture (as well as other gases and dust) from the point of origin to remote locations thousands of miles away. While about 30 [...]

For the first half of the Cenozoic (the era spanning 65 million years ago to today), Earth was too warm to support ice sheets and sea levels were much higher than today. Then, about 34 million years ago, the Earth crossed a threshold. Over a period of about 300,000 years, the temperature dropped and ice [...]

Ninety (90) percent of Earth’s ice sits on top of Antarctica, a 5.4 million square mile continent. Virtually all of this area is covered by an ice sheet that can be three miles high with an average thickness of 1.24 miles, giving it an approximate total volume of 7.2 million cubic miles.
For Comparison: The [...]

In Brief: Higher temperatures are reducing America’s snowfall, with a few regional exceptions.
Snow is not just an inhibitor of holiday travelers, nor is it just a passive product of prevailing weather conditions. Snow is a weather maker in and of itself. Snow-covered ground reflects far more of the sun’s radiation than it otherwise would and [...]

In Brief: Less ice cover on the Great Lakes is contributing to more snow regional lake effect snow.
Over much of the U.S., the 20th century warming trend means less snow and more rain. In most areas, the lack of cold limits snowfall, but this is not true in the Great Lakes region. Here, temperatures are [...]

Since at least 1960, more of Earth’s land glaciers have been shrinking than growing. As these glaciers shrink, they absorb heat from the atmosphere. To release the amount of energy that the glaciers have absorbed over the last 50 years, how many one-megaton hydrogen bombs would you need to detonate?
a)    200
b)    1000
c)    50,000
[...]

On average, about 20 trillion grams (20 teragrams) of dust are suspended in Earth’s atmosphere, where the dust particles stay for an average of 21 days. Dust is an important part of Earth’s climate – dust affects how clouds develop and how much sunlight reaches the Earth, which affects rainfall. The Dust Bowl of the [...]

Two of the biggest ice masses on Earth are the Greenland and Antarctic ice sheets, which together hold more than 90 percent of Earth’s ice. These ice sheets, particularly the Antarctic ice sheet, help to keep the planet cool by reflecting the sun’s energy. As the Earth begins to warm, the ice melts, which works [...]

In today’s modern Holocene climate, warm surface waters in the tropical oceans gradually transition into the near-freezing surface waters near the poles. During warmer periods of Earth’s distant past, this temperature gradient was far less pronounced. In the early Eocene epoch (56-53 million years ago), average annual temperatures in Siberia and Canada were about 65 [...]

During winter, Lake Superior’s cold water is on the surface and warm water is on the bottom; during summer, the opposite is the case. The “switchover” happens in the late spring or early summer and is an important event, as it “stirs” the water. This stirring brings nutrients (which feed the lake’s wildlife) from the [...]

The rich waters in Alaska’s Arctic and sub-Arctic estuaries provide the Pacific Brant, a small goose that travels in flocks of as many as 500 birds, with a steady supply of eelgrass (its principle food source) during the summer months. Traditionally (before the late 1970’s), almost 90 percent of the population would spend their summers [...]

About 75 percent of the West’s water resources originate in snowpack. Most precipitation in the region occurs during the winter, the period of the year when the reservoirs are replenished after the dry summer and early fall months. The reservoirs are at their high points in the spring. Traditionally, snowpack would last into the late [...]