まとめ
核戦争は,極端な寒さと暗闇を含む深刻な地球規模の気候変動を引き起こし,生存者を脅かす可能性があります. 100メガトンの衝突でも,世界中の大気と気候に重大な影響を及ぼす可能性があります.
科学分野:
- 大気科学 大気科学
- 気候学 気候学
- 核冬研究 核冬研究
背景:
- 火山噴火のモデルは,核戦争の影響を評価するための基礎を提供します.
- 以前の研究では,大規模な出来事による潜在的な大気変動が強調されています.
研究 の 目的:
- 核戦争の地球規模の大気と気候の影響を調査する.
- 核爆発が太陽放射線,温度,放射能の分布に及ぼす潜在的な影響を決定する.
主な方法:
- 火山噴火の研究のために開発されたモデルを利用した.
- 異なる出力 (例えば100メガトンから5000メガトン) のシミュレーションされた核交換.
- 粉塵と煙の注入,太陽放射線の減弱,温度変化,放射性降下物などを分析した.
主要な成果:
- 塵と煙による太陽放射線の減少と凍り付く温度が大幅に減少する可能性が高い.
- 比較的小さな衝突 (100メガトン) でさえも,大きな光学および気候効果を引き起こす可能性があります.
- 放射性降下物と増強した紫外線は,生存者に長期的な脅威をもたらす.
結論:
- 核戦争は,地球温暖化と人類の存続に重大な脅威をもたらす.
- 深刻な気候の影響を及ぼす値は,これまで考えられていたよりも低いかもしれません.
- 大気中の粒子や放射性物質の輸送は,両半球に影響を及ぼします.
関連する概念動画
Nuclear Fission
Many heavier elements with smaller binding energies per nucleon can decompose into more stable elements that have intermediate mass numbers and larger binding energies per nucleon—that is, mass numbers and binding energies per nucleon that are closer to the “peak” of the binding energy graph near 56. Sometimes neutrons are also produced. This decomposition of a large nucleus into smaller pieces is called fission. The breaking is rather random with the formation of a large number of different...
Nuclear Power
Controlled nuclear fission reactions are used to generate electricity. Any nuclear reactor that produces power via the fission of uranium or plutonium by bombardment with neutrons has six components: nuclear fuel consisting of fissionable material, a nuclear moderator, a neutron source, control rods, reactor coolant, and a shield and containment system.
Nuclear Fuels
Nuclear fuel consists of a fissile isotope, such as uranium-235, which must be present in sufficient quantity to provide a...
Nuclear Fuels
Nuclear fuel consists of a fissile isotope, such as uranium-235, which must be present in sufficient quantity to provide a...
Nuclear Transmutation
Nuclear transmutation is the conversion of one nuclide into another. It can occur by the radioactive decay of a nucleus, or the reaction of a nucleus with another particle. The first manmade nucleus was produced in Ernest Rutherford’s laboratory in 1919 by a transmutation reaction, the bombardment of one type of nuclei with other nuclei or with neutrons. Rutherford bombarded nitrogen-14 atoms with high-speed α particles from a natural radioactive isotope of radium and observed protons being...
Nuclear Stability
Protons and neutrons, collectively called nucleons, are packed together tightly in a nucleus. With a radius of about 10−15 meters, a nucleus is quite small compared to the radius of the entire atom, which is about 10−10 meters. Nuclei are extremely dense compared to bulk matter, averaging 1.8 × 1014 grams per cubic centimeter. If the earth’s density were equal to the average nuclear density, the earth’s radius would be only about 200 meters.
To hold positively charged protons together in the...
To hold positively charged protons together in the...
Nuclear Fusion
The process of converting very light nuclei into heavier nuclei is also accompanied by the conversion of mass into large amounts of energy, a process called fusion. The principal source of energy in the sun is a net fusion reaction in which four hydrogen nuclei fuse and ultimately produce one helium nucleus and two positrons.
A helium nucleus has a mass that is 0.7% less than that of four hydrogen nuclei; this lost mass is converted into energy during the fusion. This reaction produces about...
A helium nucleus has a mass that is 0.7% less than that of four hydrogen nuclei; this lost mass is converted into energy during the fusion. This reaction produces about...
Global Climate Change
Throughout its ~4.5 billion year history, the Earth has experienced periods of warming and cooling. However, the current drastic increase in global temperatures is well outside of the Earth’s cyclic norms, and evidence for human-caused global climate change is compelling. Paleoclimatology, the study of ancient climate conditions, provides ample evidence for human-caused global climate change by comparing recent conditions with those in the past.


