21世紀の海面上昇に対する氷河の貢献に対する運動的制約
W T Pfeffer1, J T Harper, S O'Neel
1Institute of Arctic and Alpine Research, University of Colorado, Boulder, CO 80309, USA. pfeffer@tintin.colorado.edu
Science (New York, N.Y.)
|September 6, 2008
まとめ
2100年までに海面が2メートル以上上昇することは,物理的に不可能です. 合理的で加速された条件では,海面上昇は約0.8mの上昇を示唆し,将来の海面上昇予測のベースラインを提供している.
科学分野:
- 氷河学 氷河学とは
- 気候科学 気候科学
- 海面上昇に関する研究
背景:
- 気候モデルと過去の状況は,2100年までにマルチメーターの海面上昇の可能性を示唆しています.
- 以前の予測は,極端な海面上昇のシナリオのための氷河学的条件を完全に制限しませんでした.
研究 の 目的:
- 2100年までにマルチメーターの海面上昇の氷河学的実現可能性を評価する.
- 海面上昇予測のための物理的に妥当なシナリオを確立する.
主な方法:
- 氷床の質量損失を大きくするために必要な氷河学的条件の分析.
- 氷の流れ動力の物理的限界に基づく制約されたシナリオの開発.
- 様々な加速率の下でのモデル化された海面上昇の比較.
主要な成果:
- 2100年までに海面上昇が2メートルを超えると,現在の理解では物理的に維持できないと考えられています.
- 2100年までに海面が2メートル上昇することは,すべての変数の極端で急速な加速の下でのみ可能である.
- もっと妥当で加速された条件は,2100年までに海面が合計で約0.8メートル上昇することを示しています.
結論:
- 2100年までに海面上昇が物理的に妥当であることの上限は,いくつかの提案されたシナリオよりも著しく低い.
- この結果は,気候モデルの精錬に不可欠な海面上昇の"最も可能性が高い"範囲を提供します.
- 将来の海平面予測には,詳細な氷の流れ動態と現実的な氷河学的制約が含まれなければならない.
関連する概念動画
01:50Global 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.
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...
01:26Influence of Earth's Curvature and Atmospheric Refraction on Leveling
During leveling, the Earth's curvature and atmospheric refraction introduce deviations in the line of sight from a true horizontal reference. When the line of sight is leveled, it remains perpendicular to the plumb line only at a single point. Beyond this, it deviates due to the Earth’s curvature, represented by the correction C. For a sight distance D, the deviation can be derived using the relationship:This relationship shows that the deviation increases quadratically with distance. Over a...
01:06Tidal Forces
The origin of Earth's ocean tides has been a subject of continuous investigation for over 2000 years. However, the work of Newton is considered to be the beginning of the proper understanding of the phenomenon. Ocean tides are the result of gravitational tidal forces. These same tidal forces are present in any astronomical body; they are responsible for the internal heat that creates the volcanic activity on Io, one of Jupiter's moons, and the breakup of stars that get too close to black holes.
01:03Precipitation Gravimetry
Precipitation gravimetry is based on converting an analyte into a sparingly soluble precipitate, which is separated by filtration and weighed. An ideal precipitate should be pure, insoluble, of known composition, and easily filtered from the reaction mixture.
In determining nickel by gravimetric analysis, a precipitant of ethanolic dimethylglyoxime is added to a hot nickel salt solution. This is quickly followed by the dropwise addition of dilute ammonia solution until precipitation occurs. A...
In determining nickel by gravimetric analysis, a precipitant of ethanolic dimethylglyoxime is added to a hot nickel salt solution. This is quickly followed by the dropwise addition of dilute ammonia solution until precipitation occurs. A...
01:12Temperature Dependent Deformation
In a nonhomogeneous rod made up of steel and brass, restrained at both ends and subjected to a temperature change, several steps are involved in calculating the stress and compressive load. Due to the problem's static indeterminacy, one end support is disconnected, allowing the rod to experience the temperature change freely. Next, an unknown force is applied at the free end, triggering deformations in the rod's steel and brass portions. These deformations are then calculated and added together...