海洋は,人為的なCO2のために沈む
Christopher L Sabine1, Richard A Feely, Nicolas Gruber
1National Oceanic and Atmospheric Administration (NOAA) Pacific Marine Environmental Laboratory, 7600 Sand Point Way NE, Seattle, WA 98115, USA. chris.sabine@noaa.gov
Science (New York, N.Y.)
|July 17, 2004
まとめ
海は1800年から1994年の間に,人間による二酸化炭素 (CO2) 排出量の48%を吸収した. この研究は,海洋の二酸化炭素吸収と大気中の二酸化炭素レベルを軽減する役割を定量化しています.
科学分野:
- 海洋学 海洋学 海洋学
- 気候科学 気候科学
- バイオジオケミストリー バイオジオケミストリー
背景:
- 大気中の二酸化炭素 (CO2) の濃度上昇は,気候変動の主な要因である.
- 海洋および陸上の沈殿所を含む地球規模の炭素循環を理解することは,気候モデリングに不可欠です.
- 以前,海洋のCO2吸収量に関する推定値は変化しており,精密な測定が必要であった.
研究 の 目的:
- 1800年から1994年までの世界の海洋における人為的な二酸化炭素 (CO2) の沈没を定量化するために.
- 海洋に吸収される化石燃料とセメント製造の排出量の割合を決定する.
- 同じ期間の地上生物圏からのCO2の純フローを推論する.
主な方法:
- 1990年代に実施された世界的な海洋調査から得られた無機炭素の測定値を利用した.
- 人為CO2と天然の海洋炭素を区別するために,トレーサーベースの分離技術を使用しました.
- 指定された歴史的期間における海洋における累積的なCO2吸収を計算した.
主要な成果:
- 1800年~1994年の世界の海洋における人類によるCO2吸収量は118 +/- 19ペタグラムと推定されている.
- 海洋の沈殿地は,人類によるCO2排出量の約48%を吸収していることが判明した.
- 地上生物圏がCO2の純源として作用し,大気中に39 +/- 28ペタグラムの炭素を放出したと推論した.
- 現在,海洋は,その長期的な潜在的な人類によるCO2容量の約3分の1を貯蔵していることが示されています.
結論:
- 海洋は,人類によるCO2排出量の軽減に重要な役割を果たし,1800年~1994年の排出量のほぼ半分を吸収しています.
- この時期,地上の生物圏は,いくつかの仮定に反して,大気中のCO2の純源であった.
- 人為的なCO2を吸収する海洋の能力は相当なものですが,現在の吸収量は,その総潜在力のほんの一部にすぎません.
関連する概念動画
01:14The Carbon Cycle
Carbon is the basis of all organic matter on Earth, and is recycled through the ecosystem in two primary processes: one in which carbon is exchanged among living organisms, and one in which carbon is cycled over long periods of time through fossilized organic remains, weathering of rocks, and volcanic activity. Human activities, including increased agricultural practices and the burning of fossil fuels, has greatly affected the balance of the natural carbon cycle.
01:22The Sulfur Cycle
Sulfur, an important element in the chemical makeup of proteins, is recycled through the atmosphere and aquatic and terrestrial environments. Found in the atmosphere as sulfur dioxide (SO2), sulfur is released by decaying organisms, weathered rocks, geothermal vents, volcanos, and burning fossil fuels. It is deposited into the ecosystem, cycled through the biotic community, and either released back into the atmosphere as gas or deposited in marine sediment for long-term storage and eventual...
01:19Carbon Dioxide Transport in the Blood
Carbon dioxide (CO2) transport in the blood is critical to human physiology. On average, our body cells produce around 200 mL of CO2 per minute, precisely the quantity expelled by the lungs. This process involves the transportation of CO2 from the tissue cells to the lungs in three primary forms.
Forms of CO2 Transport
1. Dissolved in plasma: A small percentage (7-10%) of CO2 is transported and dissolved directly in the plasma.
2. Carbaminohemoglobin: Just over 20% of CO2 is chemically bound to...
Forms of CO2 Transport
1. Dissolved in plasma: A small percentage (7-10%) of CO2 is transported and dissolved directly in the plasma.
2. Carbaminohemoglobin: Just over 20% of CO2 is chemically bound to...
01:28Carbon-dioxide Fixation
Carbon dioxide fixation in prokaryotes enables the assimilation of inorganic carbon into organic molecules, supporting biosynthetic pathways, sustaining ecosystems, and contributing to the global carbon cycle. It also has industrial applications in carbon capture and bioproduct synthesis. Autotrophic organisms rely on this process to utilize CO₂ as a carbon source in diverse environments.The Calvin CycleThe Calvin cycle is the most widespread carbon fixation mechanism, primarily used by...
01:24Microbes and the Carbon Cycle
The carbon cycle is a fundamental Earth process involving the transfer of carbon among the biosphere, lithosphere, atmosphere, and hydrosphere. It plays a critical role in regulating the planet’s climate and supporting life by cycling carbon through various chemical forms and reservoirs. Carbon primarily circulates as carbon dioxide (CO₂), representing its oxidized form, while reduced forms such as methane (CH₄) and organic compounds also play essential roles.Microbial activity is central to...
01:27Microbes and Climate Change
Microorganisms are pivotal agents in Earth's biogeochemical cycles, significantly influencing climate dynamics through their metabolic activities. These microbes modulate the levels of key greenhouse gases by both contributing to and helping mitigate climate change.Microbial Contributions to Greenhouse Gas EmissionsRising global temperatures accelerate microbial metabolism, which, in turn, speeds up the decomposition of organic matter. This process releases carbon dioxide (CO₂) through...