Cloud-tracked winds for the first Mars Global Surveyor mapping year
Cloud-tracked winds for the first Mars Global Surveyor mapping year
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第一个火星全球探测者测绘年的云跟踪风
DOI：
10.1029/2003je002107
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发表时间：
2003
期刊：
影响因子：
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通讯作者：
A. Ingersoll
中科院分区：
文献类型：
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作者：
Huiqun Wang;A. Ingersoll
我们在第一个测绘年（LS 135°-360°-111°）连续拍摄的火星全球勘测者（MGS）火星轨道器相机（MOC）广角全球地图带中使用云运动测量风。本文提供了在北极地区Ls 135°-195°（夏末/初秋）和Ls 20°-55°（仲春）以及在南极地区Ls 337°-10°（夏末/初秋）期间收集的11，200个风矢量。对于覆盖良好的情况下，我们还提出了派生的平均纬向和纬向风和相关的涡。在北方夏末，60°N-70°N纬向风风速以10.6m/s/°L_s的速率增加，而在南方夏末，60°S-70°S纬向风风速以10.7m/s/°L_s的速率增加。从北方盛夏至北方初秋50°N-75°N范围内纬向风的纬向分布表明，高纬度地区的风总体上弱于低纬度地区，但随时间增长的速率在高纬度地区较快。在90°W-0°-30 ° E范围内，北极地区存在一个气旋式环流。中夏末北极地区周平均纬向风场、双周平均涡动动量通量场和涡动动能场存在大尺度波动。北部的云迹风与大气环流模式计算的风基本一致，但似乎比假设地面无流动的热发射光谱仪（TES）观测的梯度风更强。
We have measured winds using cloud motion in consecutive Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) wide-angle global map swaths taken during the first mapping year (L s 135°–360°–111°). We present a total of ∼11,200 wind vectors collected in the north polar region during L_s 135°–195° (late summer/early fall) and L_s 20°–55° (mid spring) and in the south polar region during L_s 337°–10° (late summer/early fall). For cases with good coverage, we also present the derived mean zonal and meridional winds and the associated eddies. The speed of the zonal winds in 60°N–70°N increases at ∼0.6 m/s/°L_s in late northern summer, and that in 60°S–70°S increases at a rate of ∼0.7 m/s/°L_s in late southern summer. The latitudinal distribution of zonal wind within 50°N–75°N from mid northern summer to early northern fall indicates that winds at higher latitudes are generally weaker than those at lower latitudes, but the rate of increase with time is faster at higher latitudes. There is a cyclonic gyre in the 90°W–0°–30°E sector in the north polar region. There are large-scale waves in the weekly mean meridional wind and in the biweekly mean eddy momentum flux and eddy kinetic energy fields in the north polar region from mid to late summer. The cloud-tracked winds in the north are generally consistent with winds calculated by general circulation model at the water condensation level derived from MGS Thermal Emission Spectrometer (TES) observations but appear stronger than the gradient winds derived from TES assuming no flow at the surface.