Study of the Spatial and Temporal Distribution of Atmospheric Gravity Waves Using Pressure Data From the Dense USArray Transportable Array

利用密集 USArray 可移动阵列的压力数据研究大气重力波的时空分布

• 批准号: 1358520
• 负责人: Catherine de Groot-Hedlin
• 金额: $ 35.94万
• 依托单位: University of California-San Diego Scripps Inst of Oceanography
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-12-15 至 2017-11-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1358520&HistoricalAwards=false
• 关键词: Study; Spatial; Temporal; Distribution; Atmospheric

Non-technical statementThe National Science Foundation has provided funds for an unprecedented observatory for study of the Earth's interior and the atmosphere. The USArray Transportable Array is a 400-station observatory that places broadband seismic and atmospheric pressure sensors on a Cartesian grid every 70 km across an area that spans 2,000,000 square km. Seismic data from these stations have provided high-resolution images of the Earth's interior beneath the continental United States, whereas the atmospheric data at these stations provide measurements of atmospheric phenomena. In a project recently funded by NSF, researchers at UCSD developed a method to detect very long wavelength pressure disturbances, and described how they traveled across the TA. Discussions with atmospheric researchers confirmed that these pressure disturbances detected on the Earth's surface coincided with gravity waves detected by satellite measurements, at 30-50 km altitude.In this research, the researchers are making further direct comparisons of satellite observations of gravity waves with pressure disturbances recorded at ground level, with the goal of determining when and where these phenomena occur. Since gravity waves play a large part in transferring energy from near the Earth's surface to the upper atmosphere, this research is contributing to the understanding of global atmospheric circulation. Technical AbstractThe upgrade of NSF's EarthScope/USArray Transportable Array (TA) to include air pressure sensors at each station has opened up new avenues for research into atmospheric phenomena and the interaction of the atmosphere and solid Earth. This network places high quality pressure sensors on a regular, dense Cartesian grid across an area of about 2,000,000 square km, a configuration that allows for quantitative analyses of a broad range of atmospheric wave phenomena. The UCSD group is using the new pressure data to study atmospheric gravity waves at the mid-latitudes spanned by the TA. The UCSD group has developed a technique to detect gravity waves with wavelengths greater than 100 km and characterize their propagation across the TA, yielding a quantitative measure of how their characteristics (speed, direction, period, and amplitude) may change with location across the full footprint of the TA. The method reduces the large volume of data from the TA into a quantitative record that can be used for further study.The research includes a collaboration with Dr Lars Hoffmann (Juelich Supercomputing Centre) to compare gravity waves detected using satellite radiance data with those detected using UCSD's technique applied to TA pressure data. Satellites and ground-based pressure sensors provide fundamentally different platforms for studies of atmospheric gravity waves. Although these datasets and the analytical methods applied to them are completely different, a preliminary comparison of the results suggests agreement between the two. There are two main objectives of this effort. First, TA recordings of large convective events are being studied in detail and compared with satellite recordings of the same events. The objective is to determine whether gravity waves detected at ground-sited pressure sensors are coincident in time and location with stratospheric gravity waves, and whether gravity waves detected within the footprint of the TA are dominantly convective or orogenic in origin. The UCSD group is studying and documenting other characteristics of the detected gravity waves; specifically their speed, amplitude and direction. Second, a statistical study of the occurrence of gravity waves is being conducted with the objective of determining the diurnal, seasonal and regional trends in the occurrence rates of gravity waves. A key deliverable of this effort is the statistics of gravity waves during the 4-year study. The proposed research is contributing both to atmospheric science and to improved understanding of the effects of gravity waves on infrasound propagation.

非技术性陈述国家科学基金会为研究地球内部和大气的前所未有的天文台提供了资金。 USARRAY可运输阵列是一个400个稳定的天文台，在跨度为2000,000平方公里的区域，将宽带地震和大气压力传感器置于笛卡尔网格上。 来自这些站点的地震数据为美国大陆下方的地球内部提供了高分辨率图像，而这些站点的大气数据提供了大气现象的测量。 在NSF最近资助的项目中，UCSD的研究人员开发了一种检测非常长的波长压力干扰的方法，并描述了它们如何跨过TA。与大气研究人员的讨论证实，在地球表面检测到的这些压力干扰与卫星测量值检测到的重力波相吻合，在30-50 km的高度下。在这项研究中，研究人员正在对重力波的卫星观察结果进行进一步的直接比较，并在地面上记录了压力干扰，并确定了这些现象的目标。由于重力波在将能量从地面附近转移到上层大气中起着很大的作用，因此这项研究有助于理解全球大气循环。技术摘要NSF的Earthscope/USARRAY可运输阵列（TA）的升级包括每个站点的气压传感器，为大气现象以及大气和固体土的相互作用开辟了新的途径。该网络将高质量的压力传感器放置在约2,000,000平方公里的面积的常规密集的笛卡尔网格上，这种配置允许对广泛的大气波现象进行定量分析。 UCSD组正在使用新的压力数据来研究由TA跨越的纬度中的大气重力波。 UCSD组开发了一种技术来检测波长大于100 km的重力波，并表征了它们在TA上的传播，从而定量衡量了其特性（速度，方向，周期和振幅）的特性如何随着位置而变化。 该方法将大量数据从TA减少到可用于进一步研究的定量记录中。该研究包括与Lars Hoffmann博士（Juelich Super Computing Center）的合作，以比较使用卫星辐射数据检测到的重力波与使用UCSD技术应用于TA压力数据的技术。卫星和地面压力传感器提供了根本不同的平台，用于研究大气重力波。 尽管这些数据集和应用于它们的分析方法是完全不同的，但对结果的初步比较表明两者之间一致。这项工作有两个主要目标。首先，正在详细研究大型对流事件的录音，并将其与相同事件的卫星录音进行比较。目的是确定在地面压力传感器下检测到的重力波是否在时间和位置与平流层重力波一致，以及在TA的足迹中检测到的重力波是否在起源上是对对流或造基因的主要对流或造基因。 UCSD组正在研究并记录检测到的重力波的其他特征。特别是它们的速度，振幅和方向。 其次，正在进行对重力波发生的统计研究，目的是确定重力波发生率的昼夜，季节和区域趋势。这项工作的关键可交付是在4年研究中重力波的统计数据。 拟议的研究既有助于大气科学，也有助于改善对重力波对反向传播的影响的理解。