格陵兰岛尖端喷气的迫使在伊明格海的深度对流
Robert S Pickart1, Michael A Spall, Mads Hvid Ribergaard
1Woods Hole Oceanographic Institution, Woods Hole, Massachusetts 02543, USA. rpickart@whoi.edu
Nature
|July 11, 2003
概括
对于海洋循环至关重要的深海对流现在在伊明格海中被观察到. 格陵兰岛的尖端喷流定期触发这个过程,与其他已知的深水形成地点不同.
科学领域:
- 海洋学 海洋学 海洋学
- 大气科学 大气科学
- 气候科学 气候科学
背景情况:
- 开放海洋深层对流是全球海洋循环中的一个关键过程,主要发生在地中海和拉布拉多海等有限地区.
- 伊明格海最近被确定为潜在的深层对流的新地点.
- 在伊明格海中形成的深水与北大西洋中深水具有共同的特征,以前认为其来源仅来自拉布拉多盆地.
研究的目的:
- 为了调查开放的海洋深度对流的原因在西南欧明格海.
- 确定大气条件的作用,特别是格陵兰的尖端喷流,在触发对流方面.
- 了解这个新的对流点对北大西洋循环的影响.
主要方法:
- 来自陆地站的历史气象数据的分析,以确定格陵兰的尖端喷气事件.
- 使用区域海洋数值模型来模拟深层对流.
- 与北大西洋振荡指数和观测数据相关联的对流事件.
主要成果:
- 格陵兰岛尖端喷气,在Farewell角附近定期发生的低层大气喷气,被认为是Irminger海深层对流的首要驱动力.
- 当北大西洋振荡指数很高,与观测数据保持一致时,会发生对流.
- 在伊明杰海,驱动对流的机制与地中海和拉布拉多海的机制不同.
结论:
- 格陵兰岛尖端喷流是启动开放海洋深层对流在伊明格海的一个重要因素.
- 这一发现扩大了我们对深水形成及其在北大西洋的地理分布的理解.
- 欧明格海独特的对流机制凸显了大气强迫和海洋学过程之间的复杂相互作用.
相关概念视频
01:21Isothermal Processes
3.8K
A thermodynamic process that occurs at constant temperature is called an isothermal process. Heat slowly flows into the system or out of the system to maintain thermal equilibrium. Processes involving phase changes like water evaporation into steam or freezing water into ice at a constant temperature are examples of Isothermal Processes.
An ideal gas can also undergo isothermal expansion or compression.
For example, consider 1 mole of an ideal gas inside an isolated cylinder at initial volume V...
An ideal gas can also undergo isothermal expansion or compression.
For example, consider 1 mole of an ideal gas inside an isolated cylinder at initial volume V...
3.8K
01:28Magnetostatic Boundary Conditions
1.9K
An electric field suffers a discontinuity at a surface charge. Similarly, a magnetic field is discontinuous at a surface current. The perpendicular component of a magnetic field is continuous across the interface of two magnetic mediums. In contrast, its parallel component, perpendicular to the current, is discontinuous by the amount equal to the product of the vacuum permeability and the surface current. Like the scalar potential in electrostatics, the vector potential is also continuous...
1.9K
01:23Coriolis Force
7.7K
An accelerating particle experiences a force equal to the mass multiplied by the acceleration in an inertial frame of reference. Consider a particle in a non-inertial frame of reference, such as a sliding ball on a rotating table. The acceleration of the ball in this rotating reference frame is different than in the intertial frame, which modifies its equation of motion. The fictitious forces acting additionally on a rotating frame of reference alter Newton's Second Law expression.
7.7K
01:28Irrotational Flow
1.3K
Irrotational flow is characterized by fluid motion where particles do not rotate around their axes, resulting in zero vorticity. For a flow to be irrotational, the curl of the velocity field must be zero. This imposes specific conditions on velocity gradients. For instance, to maintain zero rotation about the z-axis, the gradient condition:
1.3K
01:22Couette Flow
1.4K
Couette flow represents the flow of fluid between two parallel plates, with one plate fixed and the other moving with a constant velocity. This configuration allows for a simplified analysis using the Navier-Stokes equations, which govern fluid motion under conditions of viscosity and incompressibility. For Couette flow, the assumptions include a steady, laminar, incompressible flow with a zero-pressure gradient in the flow direction. This flow type is beneficial for understanding shear-driven...
1.4K
01:18Deep Sea Microbial Ecology
53
The deep ocean and its underlying sediments represent vast, largely unexplored microbial habitats that extend far beyond the sunlit photic zone. The photic (euphotic) zone typically spans the upper ~100–200 meters of pelagic waters in the open ocean, but its depth varies geographically and seasonally, where sufficient light supports photosynthetic life. Below this lies the deep sea, spanning roughly 1000–6000 meters (bathypelagic to abyssal zones), with deeper hadal trenches...
53