Humans are also adding small particles called aerosols to the air, from smokestacks, airplanes, and the tailpipes of cars. ![]() If that surface is darker than the forest cover, the Earth absorbs more solar radiation where it’s lighter, like in the arctic, more sunlight is reflected back into space. ![]() For example, by cutting down forests, we have exposed more of the Earth’s surface to sunlight. The biggest change has been the greenhouse gases we have added to the atmosphere, which keep heat from escaping the Earth. For example, the Intergovernmental Panel on Climate Change uses 1750 as a baseline year.Ĭompared to this baseline, radiative forcing can directly measure the ways recent human activities have changed the planet’s climate. For this reason, researchers calculate radiative forcing based on a “baseline” year sometime before the beginning of world industrialization. A changing balanceīefore the industrial era, radiative forcing was in very close balance, and the Earth’s average temperature was more or less stable. However, we do know that today, more heat is coming in than going out. Many factors, including clouds, polar ice, and the physical properties of gases in the atmosphere, have an effect on this balancing act, and each has its own level of uncertainty and its own difficulties in being precisely measured. The analysis needed to pin down this exact number is very complicated. Radiative forcing measures how much energy is coming in from the sun, compared to how much is leaving. But as with any warm object sitting in cold surroundings-and space is a very cold place-some energy from Earth is always radiating back out into space as heat. Some of this sunlight (about 30 percent) is reflected back to space. Sunlight is always shining on half of the Earth’s surface. This is called radiative forcing because the difference in energy can force changes in the Earth’s climate. If more radiation is entering Earth than leaving-as is happening today-then the atmosphere will warm up. Energy travels in the form of radiation: solar radiation entering the atmosphere from the sun, and infrared radiation exiting as heat. Regulation of LLW disposal is regulated by both the NRC and Agreement States, and waste regulation is also supported by the agency's Radioactive Waste Safety Research program.Radiative forcing is what happens when the amount of energy that enters the Earth’s atmosphere is different from the amount of energy that leaves it. The NRC's Regional Offices ( Region I - Northeast, Region II - Southeast, Region III - Midwest, and Region IV - West/Southwest) implement these programs in the States for which they are responsible. The Office of Nuclear Material Safety and Safeguards (NMSS) develops and implements NRC policy for the regulation and safe management and disposal of spent fuel and HLW develops guidance for environmental compliance, and oversees the decommissioning and cleanup of contaminated sites, safe management and disposal of LLW, and uranium recovery activities. For example, regulation of uranium mill waste is covered under the Nuclear Materials program. Regulation of some activities associated with radioactive waste is covered under either the Nuclear Materials or Nuclear Reactors regulatory programs. Regulated Activitiesįor general information, see the How We Regulate page. Nuclear Regulatory Commission (NRC) does not regulate all sources of radioactivity see Who Regulates Radioactive Materials and Radiation Exposure for details. Uranium mill tailings are the residues remaining after the processing of natural ore to extract uranium and thorium.High-level waste (HLW) is "irradiated" or used nuclear reactor fuel.Department of Energy (DOE) has distinguished from high-level waste (described below) Waste incidental to reprocessing (WIR) refers to certain waste byproducts that result from reprocessing spent nuclear fuel, which the U.S.Low-level waste (LLW) includes radioactively contaminated protective clothing, tools, filters, rags, medical tubes, and many other items.Find the locations of low-level waste disposal facilities, high-level waste disposal facilities, and disposal facilities for waste incidental to reprocessing.
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