High frequency fluctuations in the heat content of an ocean general circulation model
High frequency fluctuations in the heat content of an ocean general circulation model
复制标题
海洋环流模型热含量的高频波动
DOI：
--
复制
发表时间：
2012
期刊：
影响因子：
--
通讯作者：
D. Webb
中科院分区：
文献类型：
--
作者：
A. Huerta;D. Webb
抽象的。海洋的热量运输和储存至关重要，因为它对海洋动力学产生影响，并对大气、气候和气候变化产生影响。不幸的是，由于可收集和存储的数据量有限，许多热量收支的实验和模拟研究不得不利用平均数据集，在这些数据集中，短期波动的影响已经消失。本文利用高分辨率全球海洋模式OCCAM的数据，研究了误差的大小。该模型每一步都会进行适当的热平衡，因此在分析中发现的任何不平衡都一定是由于使用平均场造成的。这项研究集中在影响厄尔尼诺现象的两个海洋区域。第一个是赤道以北的热带不稳定波区域。第二个是赤道沿岸的上升流区。结果表明，在这两种情况下，周期少于5天的过程都会对热量预算产生显著影响。因此，使用平均超过五天或更长时间的数据进行分析可能会有重大错误。文中还指出，如果有一系列瞬时值，就可以对误差的大小作出合理的估计。在模型研究中，这些值以用于重新启动模型的数据集的形式提供。在实验研究中，它们可能是以个体非平均观测的形式出现的。
Abstract. The transport and storage of heat by the ocean is of crucial importance because of its effect on ocean dynamics and its impact on the atmosphere, climate and climate change. Unfortunately, limits to the amount of data that can be collected and stored mean that many experimental and modelling studies of the heat budget have to make use of mean datasets where the effects of short term fluctuations are lost. In this paper we investigate the magnitude of the resulting errors by making use of data from OCCAM, a high resolution global ocean model. The model carries out a proper heat balance every time step so any imbalances that are found in the analysis must result from the use of mean fields. The study concentrates on two areas of the ocean affecting the El Nino. The first is the region of tropical instability waves north of the Equator. The second is in the upwelling region along the Equator. It is shown that in both cases, processes with a period of less than five days can have a significant impact on the heat budget. Thus, analyses using data averaged over five days or more are likely to have significant errors. It is also shown that if a series of instantaneous values is available, reasonable estimates can be made of the size of the errors. In model studies, such values are available in the form of the datasets used to restart the model. In experimental studies they may be in the form of individual unaveraged observations.