U.S. Geothermal Power at Present

Part 5 of Geothermal Energy Under Our Feet. Today’s U.S. geothermal industry is a $2-billion per-year enterprise involving over 2800 MW of electricity generation capacity, about 620 MW of thermal energy capacity in direct-use applications such as indoor heating, greenhouses, food drying, and aquaculture, and over 7,300 MW of thermal energy capacity from geothermal heat […]

Global Climate Scenarios: Emissions

Part 8 of United States Climate Change Impact. Some continued warming of the planet is projected over the next few decades due to past emissions. Choices made now will influence the amount of future warming. Lower levels of heat-trapping emissions will yield less future warming, while higher levels will result in more warming, and more […]

Climate Change and the Human Fingerprint

Part 7 of United States Climate Change Impact. There is extensive statistical evidence from so-called “fingerprint” studies. Each factor that affects climate produces a unique pattern of climate response, much as each person has a unique fingerprint. Fingerprint studies exploit these unique signatures, and allow detailed comparisons of modeled and observed climate change patterns. Scientists […]

Rising Temperatures, Carbon release and uptake and Ocean Acidification

Part 5 of United States Climate Change Impact. Carbon release and uptake Once carbon dioxide is emitted to the atmosphere, some of it is absorbed by the oceans and taken up by vegetation, although this storage may be temporary. About 45 percent of the carbon dioxide emitted by human activities in the last 50 years […]

Heat Trapping Gases & Other Climate Change Influences

Part 4 of United States Climate Change Impact. Carbon dioxide concentration has increased due to the use of fossil fuels in electricity generation, transportation, and industrial and household uses. It is also produced as a by-product during the manufacturing of cement. Deforestation provides a source of carbon dioxide and reduces its uptake by trees and […]

Global Climate Change: Introduction

Part 3 of United States Climate Change Impact. Key Messages: Human activities have led to large increases in heat-trapping gases over the past century. Global average temperature and sea level have increased, and precipitation patterns have changed. The global warming of the past 50 years is due primarily to human-induced increases in heat-trapping gases. Human […]

United States Climate Change Impact Summary

Part 2 of United States Climate Change Impact. Observations show that warming of the climate is unequivocal. The global warming observed over the past 50 years is due primarily to human-induced emissions of heat-trapping gases. These emissions come mainly from the burning of fossil fuels (coal, oil, and gas), with important contributions from the clearing […]

Geothermal Power Plants: from light to water

Part 3 of Geothermal Energy: Power from the Depths of the Earth. Flip a switch and light up a room—what could be easier? Push a button on the TV remote control and be entertained. It all seems so simple that we are often unaware of the true environmental and social cost of these conveniences—and who […]

Ethanol: Separating Fact from Fiction

When energy prices soared during the 1970s, most Americans recognized the inherent danger in the U.S.’s dependence on imported petroleum. Despite current complacency, the potential economic and national security threats have not diminished. In 1995 the United States exceeded the level of imported petroleum it reached during the 1970s. Today, in fact, more than half […]

Today’s Alternative Fuel Choices: Natural Gas

Part 6 of Advanced Technology and Alternative Fuel Vehicles. Natural gas is a mixture of hydrocarbons, mainly methane. It can be produced either from gas wells or in conjunction with crude oil production. Natural gas is a clean burning, domestically produced fuel that generates significantly less carbon monoxide, carbon dioxide, particulate matter, and nitrous oxide […]