Daily Archives March 13, 2016
Aerosols occur in the atmosphere from natural causes; for instance, they are blown off the surface of deserts or dry regions. As a result of the eruption of Mt. Pinatubo in the Philippines in June 1991, considerable amounts of aerosol were added to the stratosphere that, for approximately 2 years, scattered solar radiation leading to a loss of radiation and a cooling at the surface.
As noted previously, human activities also affect the amount of aerosol in the atmosphere. The main direct effect of aerosols, such as sulfate particles, is the scattering of some solar radiation back to space, which tends to cool the earth’s surface...Read More
Agribusiness applications (agriculture and aquaculture) are particularly attractive because they require
marketable crops have been raised in geothermally heated greenhouses in Tunisia, Hungary, Russia, New Zealand, Japan, Iceland, China, and the United States. These include vegetables such as cucumbers and tomatoes, flowers (both potted and bedded), house plants, tree seedlings, and cacti. Using geothermal energy for heating reduces operating costs (which can account for 35% of the product cost) and allows operation in colder climates where commercial greenhouses would not normally be economical.
The use of geothermal energy for raising catfish, shrimp, tilapia, eels, and tropical fish has produced crops faster than by conventional solar heating...Read More
The amount of carbon dioxide in the atmosphere has increased by more than 30% in the past two centuries since the beginning of the industrial revolution, an increase that is known to be in part due to combustion of fossil fuels and the removal of forests. Most of this increase has occurred since World War II. Because carbon dioxide is recycled through the atmosphere many times before it is finally removed, it has a long lifetime exceeding 100 years. Thus, emissions lead to a buildup in concentrations in the atmosphere. In the absence of controls, it is projected that the rate of increase in carbon dioxide may accelerate and concentrations could double from pre-industrial values within approximately the next 60 years.
If the amount of carbon dioxide in the atmosphere were suddenly doubled...Read More
Space conditioning includes both heating and cooling. Space heating with geothermal energy has widespread application, especially on an individual basis. Buildings heated from individual wells are popular in Klamath Falls, Oregon; Reno, Nevada; and Taupo and Rotorua, New Zealand. Absorption space cooling with geothermal energy has not been popular because of the high temperature requirements and low efficiency. Geothermal heat pumps (groundwater and ground coupled) have become popular in the United States, Sweden, and Switzerland for both heating and cooling.
An example of the use of space heating and cooling with low – to moderate-temperature geothermal energy is the Oregon Institute of Technology in Klamath Falls, Oregon (Fig. 4)...Read More
Climate can vary for many reasons, and in particular, human activities can lead to changes in several ways. However, to place human influences in perspective, it is worthwhile to compare the output from a power plant with that from the sun. The largest power plants that exist are on the order of 1000 MW, and these service human needs for electricity in appliances and heating that use power in units of kilowatts. Figure 2 shows that the energy received at the top of the atmosphere is 342 W m~2 on an annual mean basis averaged over the globe. This is equivalent to 175 PW, although only approximately 120 PW is absorbed. One petawatt is 1 billion MW or 1 million huge power plants...Read More
The climate system becomes more involved as the components interact. A striking example is a phenomenon that would not occur without interactions between the atmosphere and ocean, El Nino, which consists of a warming of the surface waters of the tropical Pacific Ocean. It takes place from the International Dateline to the west coast of South America and results in changes in the local and regional ecology. Historically, El Ninos have occurred approximately every 3-7 years and alternated with the opposite phases of below average temperatures in the tropical Pacific, called La Nina. In the atmosphere, a pattern of change called the Southern
Oscillation is closely linked with these ocean changes so that scientists refer to the total phenomenon as ENSO...Read More
Romans, Chinese, Ottomans, Japanese, and central Europeans have bathed in geothermal waters for centuries. Today, more than 2200 hot springs resorts in Japan draw 100 million guests every year, and the “return-to-nature’’ movement in the United States has revitalized many hot spring resorts.
The geothermal water at Xiaotangshan Sanitarium, northwest of Beijing, has been used for medical purposes for more than 500 years. Today, the 50°C water is used to treat high blood pressure, rheumatism, skin disease, diseases of the nervous system, ulcers, and generally for recuperation after surgery. In Rotorua, New Zealand, at the center of the Taupo Volcanic Zone of North Island, the Queen Elizabeth Hospital was built during World War II for U. S...Read More