表面の融解によって引き起こされるグリーンランドの氷床の流れの加速

H Jay Zwally¹, Waleed Abdalati, Tom Herring

¹Oceans and Ice Branch, Code 971, NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA. jay.zwally@gsfc.nasa.gov

Science (New York, N.Y.)

|June 8, 2002

まとめ

夏の融解は,氷床の底を潤滑することによって,グリーンランドの氷の流れを加速します. 融水の増加は氷河の滑り方を強化し,氷床の動態に影響を与え,気候変動に潜在的に反応します.

科学分野:

氷河学氷河学とは
気候科学気候科学
地球システム科学地球システム科学

背景:

グリーンランドの氷床の動態は,海面上昇を理解するために不可欠です.
表面の融水と氷の流れの関係は複雑である.
氷床の平衡地帯は,表面条件に対する様々な反応を経験します.

研究の目的:

グリーンランドの氷河流の加速に夏の表面の融解が与える影響を調査する.
融水と強化された氷河の滑り方を結びつけるメカニズムを決定する.
融解強度と氷の加速との相関を評価する.

主な方法:

グリーンランドの中央西部の氷床からの氷の流れデータの分析.
表面の融解の持続時間/強度と氷の加速速度との相関分析.
氷床と岩の接点への融水移動の役割を調査する.

主要な成果:

氷の流れは夏の融解期間に著しく加速し,真冬の速度を上回る.
氷の加速は,表面の融解の期間と強度と直接関係しています.
減速は,融解が止まった後に発生し,融解水潤滑仮説を支持する.

結論:

表面の融水は,氷床と氷床の界面に到達することによって,氷河の滑り方を強化します.
表面の融解と氷床の流れのダイナミクスの間には直接的な結合が存在します.
このメカニズムは,氷床が,融解が増加することによって,気候変動に迅速に反応することを示唆しています.

さらに関連する動画

08:16

Ice Generation and the Heat and Mass Transfer Phenomena of Introducing Water to a Cold Bath of Brine

Published on: March 13, 2017

11:20

Fabrication of Superhydrophobic Metal Surfaces for Anti-Icing Applications

Published on: August 15, 2018

関連する概念動画

02:57

Surface Tension, Capillary Action, and Viscosity

Surface Tension
The various IMFs between identical molecules of a substance are examples of cohesive forces. The molecules within a liquid are surrounded by other molecules and are attracted equally in all directions by the cohesive forces within the liquid. However, the molecules on the surface of a liquid are attracted only by about one-half as many molecules. Because of the unbalanced molecular attractions on the surface molecules, liquids contract to form a shape that minimizes the number...

01:24

Surface Tension

Surface tension is defined as the force per unit length (γ) acting along the surface of a liquid. It arises due to strong intermolecular forces of attraction. A molecule located inside the bulk of the liquid is surrounded by other molecules and experiences equal forces in all directions. However, a molecule at the surface experiences unbalanced forces because there are more neighboring molecules below than above. This creates a net inward force that pulls surface molecules toward the interior,...

01:27

Frost Action on Concrete

Concrete structures in cold climates, such as those along roadsides, can retain moisture. This moisture makes them susceptible to frost-related damage when temperatures fall below freezing. Adding moisture worsens the damage during temperature fluctuations, leading to repeated freezing and thawing. De-icing salts, spread over these structures to melt ice, add to the freeze-thaw cycle, and draw even more moisture into the concrete.
This freeze-thaw cycle primarily causes surface scaling, where...

01:22

Surface Tension of Fluid

Surface tension is a fundamental property of fluids, occurring at the boundary between a liquid and a gas or between two immiscible liquids. This phenomenon arises from the cohesive forces between molecules at the fluid's surface, creating an effect similar to a stretched elastic membrane. Inside each fluid, molecules are equally attracted in all directions by neighboring molecules, but surface molecules experience a net inward force, resulting in surface tension.
Surface tension varies with...

01:18

Boundary Layer Characteristics

When a fluid encounters a solid surface, a boundary layer forms due to the interaction between the fluid's motion and the stationary surface. This phenomenon is characterized by a thin region adjacent to the surface where viscous forces dominate, influencing the fluid's velocity profile. The development of the boundary layer begins at the leading edge of the surface and evolves as the fluid moves downstream.As the fluid flows over the surface, friction between the fluid and the wall slows down...

01:22

Surface Integrals of Vector Fields: Flux

Understanding the movement of air masses is fundamental to meteorological analysis and atmospheric modeling. A key component in this process is quantifying the total mass of air that flows into or out of a defined region over a specified period of time. This is achieved by evaluating the mass flux across a boundary surface, a conceptual tool that simplifies the complex dynamics of atmospheric systems.To begin, an imaginary boundary surface S is introduced, enclosing the region of interest. The...

関連する実験動画