Deconstructing the Hadley cell heat transport
Deconstructing the Hadley cell heat transport
复制标题
解构哈德利胞热传输
DOI：
10.1002/qj.2085
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发表时间：
2012
影响因子：
8.9
通讯作者：
Heaviside C
中科院分区：
文献类型：
--
作者：
Heaviside C
欧洲中期天气预报中心 (ECMWF) 重新分析 (ERA-40) 数据集对低纬度地区向极地大气热传输的机制进行了研究。在对流频繁的地区（即印度洋-太平洋“暖池”）发现了深层经向翻转环流，这表明这是大气热传输似乎由轴对称运动或“哈德利环流热传输”主导的主要原因。相比之下，“冷舌”地区（例如东大西洋地区）上空环流的经向质量输送分布更为复杂，并且中层湿静态能量明显最小值的存在限制了这些地区全年对极地热输送的贡献很小。然而，经历频繁对流的区域并不能解释所有年度平均极地大气热传输。在赤道，每年向南净输送的热量约为 0.4 PW（1 PW = 1015W），但在对流最活跃区域发现的深翻转单元仅贡献了其中的 25%。 ∼0.1 PW 的这一小贡献被认为反映了北方冬季和夏季分别向北和向南的大量 (∼1 PW) 热量传输之间的季节性抵消。 12月至2月，大部分跨赤道热输送来自对流区域，而6月至8月，只有一半来自对流区域。在这个季节，与亚洲夏季季风相关的强烈索马里急流带来了大量的热量。我们的诊断结果表明，索马里急流是赤道年度净南向大气热传输的重要贡献者，而不是将净南向跨赤道热传输归因于与东太平洋和大西洋全年热带对流区偏北位置相关的气候学不对称性。
The mechanisms responsible for poleward atmospheric heat transport at low latitudes are examined in the European Centre for Medium‐Range Weather Forecasts (ECMWF) Re‐Analysis (ERA‐40) dataset. Deep meridional overturning circulations are found in regions experiencing frequent convection (i.e. the Indo‐Pacific ‘warm pool’) and it is suggested that these are the primary reason why atmospheric heat transport seems dominated by axisymmetric motions or ‘Hadley cell heat transport’. In contrast, the more complex distribution of meridional mass transport by the circulations over the ‘cold tongue’ regions (such as the eastern Atlantic area) and the presence of a pronounced minimum in moist static energy at mid‐levels constrain these regions to contribute little to poleward heat transport year round. Regions experiencing frequent convection do not, however, account for all theannual meanpoleward atmospheric heat transport. At the Equator, an annual net southward transport of heat of about 0.4 PW (1 PW = 1015W) is found, but the deep overturning cells found in the most convectively active regions contribute only 25% of this. This small contribution of ∼0.1 PW is understood to reflect a seasonal cancellation between large (∼1 PW) northward and southward heat transports in boreal winter and summer respectively. During December‐February, most of the cross‐equatorial heat transport is attributable to the convective regions, whereas in June‐August, only half is attributable to these regions. In this season, there is a significant amount of heat transport by the strong Somali jet associated with the Asian summer monsoon. Rather than attributing the net southward cross‐equatorial heat transport to asymmetries in the climatology associated with the northerly position of the intertropical convection zones throughout the year over the eastern Pacific and Atlantic oceans, our diagnostics suggest that the Somali jet is a significant contributor to the annual net southward atmospheric heat transport at the Equator.
影响因子：
3.1
作者：
D. Raymond;C. Bretherton;J. Molinari
通讯作者：
J. Molinari
作为西边界流的低空急流
DOI：
--
发表时间：
1976
期刊：
影响因子：
--
作者：
David Anderson
通讯作者：
David Anderson