Subscribe Now

One of Earth’s most dramatic seasonal cycles is the waxing and waning of the sea ice that surrounds Antarctica, the driest, darkest and coldest continent. At its maximum extent at the end of the Southern Hemisphere winter in September, a 6.9 million square mile expanse of ice extends from Antarctica’s shores out into the Southern [...]

Since the 1750′s, the amount of methane (CH4) in the atmosphere has increased by 250 percent. Much of this methane is emitted from lakes in northern regions. Glacial movement across the far North (north of 45 degrees) during the last ice age leveled the landscape, carved depressions in the bedrock and deposited ice that formed [...]

Earth 13,000 years ago was in the process of thawing from the coldest part of the last ice age. Then, something sudden and catastrophic happened: within a few decades, northern Europe’s average temperature dropped by 18 degrees Fahrenheit. The sudden cold period that followed is called the Younger Dryas, named after the Arctic tundra wildflower [...]

In northern China, how much rain falls each year is controlled by the strength of the Asian Monsoon – the system of seasonal winds that bring moist marine air onto land during the summer and cold dry air out to sea during the winter. When the monsoon system is strong, there is ample rainfall and [...]

Each year, rivers originating in the surrounding mountains and forests send an average of 229 trillion gallons of freshwater into the Gulf of Alaska. The amount of water flowing into the Gulf and when most of the flow occurs affects how salty the waters in the Gulf are. How salty these waters are affects the [...]

Over the past 250 years, the amount of carbon dioxide (CO2) in the atmosphere has risen from 280 parts per million to almost 400. Plants use sunlight to convert this atmospheric carbon into the sugars and starches that make up their tissues. As the amount of carbon in the atmosphere changes, plant growth patterns change [...]

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 [...]

Better understanding how fluctuations in climate have affected regional wildfire frequency over the past few centuries may help to improve our ability to predict severe wildfire seasons. Some of the West’s older groves have experienced dozens of wildfires over the past few centuries. The trees that survived these fires recorded black scars in their annual [...]

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 [...]

While commonly considered two separate lakes, Lakes Michigan and Huron are actually hydrologically one body of water – they are connected at the Straits of Mackinaw and rise and fall in unison. Since 1980, Lake Michigan-Huron has been warming and annually averaged surface temperatures are now 3.6 degrees Fahrenheit warmer than they were in the [...]

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, [...]

In the Southern Ocean around Antarctica, strong winds accompany strong ocean currents that move carbon from the ocean surface to the depths and from the depths to the surface. This ocean is considered to be a “Carbon dioxide (CO2) sink,” or a component of Earth’s climate that takes in more atmospheric CO2 as carbon concentrations [...]

The amount of solar energy Earth receives varies according to the “11-year solar cycle,” which corresponds to a cycle in the frequency and distribution of sunspots on the sun’s surface. The difference in solar energy between high and low points of the solar cycle is about two watts per square meter. About 35 percent of [...]

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 [...]