プレイストセンの後半の脱氷期の傾斜とプレセッションの加速度を組み合わせた
1Department of Earth and Planetary Sciences, Harvard University, 20 Oxford Street, Cambridge, Massachusetts 02138, USA. phuybers@fas.harvard.edu
Nature
|December 14, 2011
まとめ
地球 地球 地球 地球 地球 地球
科学分野:
- 古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは
- 気候科学 気候科学
- 地質物理学 地質物理学とは地質物理学です.
背景:
- ミランコビッチ周期は,地球の氷河状態に影響を与えると提案されています.
- 以前の研究では,傾きが氷河周期をペースすると示唆されていたが,プレセッションの役割は不明のままだった.
- タイミングの不確実性は,脱氷の軌道強制の定量的なテストを妨げています.
研究 の 目的:
- プレイストセンの終わりの氷河周期における傾斜とプレセッションの二重効果を定量的にテストする.
- 脱氷の軌道ペースの分析における時間制御の欠陥を克服するために.
- 軌道パラメータが気候変動に及ぼす影響の組み合わせに関する確固たる証拠を提供すること.
主な方法:
- 軌道強制における最大値に焦点を当てた新しい統計テストの開発.
- プレイストセンの終わりの氷河周期の分析.
- 傾きとプレセッション効果の段階分析.
主要な成果:
- 斜率と前進の両方が,プレイストセンの終わりの氷河サイクルをペースしていることが判明しました.
- 新しい統計的方法により,タイムコントロールの問題が解決されました.
- この結果は,氷河間の状態に関するミランコビッチの仮説を裏付けている.
結論:
- 斜率とプレセシオンは協調して,プレイストセンの終わりの氷河サイクルをペースにします.
- この発見は,脱氷における軌道強制の二重の役割を確認しています.
- 南半球におけるより長い夏も,氷の解消に寄与する可能性がある.
関連する概念動画
Global Climate Change
29.9K
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.
29.9K
Gyroscope: Precession
6.1K
Precession can be demonstrated effectively through a spinning top. If a spinning top is placed on a flat surface near the surface of the Earth at a vertical angle and is not spinning, it will fall over due to the force of gravity producing a torque acting on its center of mass. However, if the top is spinning on its axis, it precesses about the vertical direction, rather than topple over due to this torque. Precessional motion is a combination of a steady circular motion of the axis and the...
6.1K
Apparent Weight and the Earth's Rotation
4.5K
Since all objects on the Earth's surface move through a circle every 24 hours, there must be a net centripetal force on each object, directed towards the center of that circle. The points of the north and south poles are the only exception to this rule.
For an object on the Earth's equator, the net centripetal force that accounts for its rotation is the Earth's pull towards its center, or the weight minus the normal force that prevents it from piercing into the Earth's surface....
For an object on the Earth's equator, the net centripetal force that accounts for its rotation is the Earth's pull towards its center, or the weight minus the normal force that prevents it from piercing into the Earth's surface....
4.5K
Atomic Nuclei: Larmor Precession Frequency
3.8K
The earth's gravitational field produces a 'twisting force' perpendicular to the angular momentum of a spinning mass (such as a spinning top) that causes the mass to 'wobble' around the gravitational field axis in a phenomenon called precession. Similarly, the magnetic moment (μ) of a spinning nucleus precesses due to an external magnetic field directed along the z-axis. The precession of the magnetic moment vector about the magnetic field is called Larmor precession,...
3.8K
Isochoric and Isobaric Processes
5.5K
A thermodynamic process that occurs at constant volume is called an isochoric process. According to the first law of thermodynamics, heat supplied or removed from the system is partially utilized to perform work and change the internal energy of the system. However, in an isochoric process, the volume remains constant. Hence, the work done by the system is zero. Therefore, the exchange of heat changes the internal energy of the system only.
Suppose 1000 g of water is heated from 40...
Suppose 1000 g of water is heated from 40...
5.5K
Curvilinear Motion: Polar Coordinates
1.2K
In polar coordinates, the motion of a particle follows a curvilinear path. The radial coordinate symbolized as 'r,' extends outward from a fixed origin to the particle, while the angular coordinate, 'θ,' measured in radians, represents the counterclockwise angle between a fixed reference line and the radial line connecting the origin to the particle.
The particle's location is described using a unit vector along the radial direction. Deriving the particle's position...
The particle's location is described using a unit vector along the radial direction. Deriving the particle's position...
1.2K


