|
| Wave effects on the retrieved wind field from the ASCAT scatterometer |
| 海浪场对ASCAT散射计反演风场的影响研究 |
| Received:March 27, 2013 Revised:July 17, 2014 |
| DOI： |
| Key words:ASCAT, wind field, wave effects, wave parameters |
| 中文关键词: ASCAT，风场，海浪影响，海浪参数 |
| 基金项目: |
|
| Hits: 753 |
| Download times: 2 |
| Abstract: |
| To improve the retrieval accuracy, this paper studies the wave effects on the retrieved wind field from scatterometer. First, the Advanced Scatterometer (ASCAT) data and buoy data of National Data Buoy Central (NDBC) are collocated. Buoy wind speed are converted into neutral wind at 10 m height. Then, ASCAT data are compared to buoy data for wind speed and direction. Subsequently, errors between ASCAT and buoy wind as a function of each wave parameter are used to analyze the wave effects. Wave parameters include dominant wave period (dpd), significant wave height (swh), average wave period (apd) and angle between dominant wave direction (dwd) and wind direction. Collocated data are divided into small data sets according to the different intervals of each wave parameter. Root Mean Square Error (RMSE) for wind speed and Mean Absolute Error (MAE) for wind direction are calculated from small data sets, which are considered as the function of wave parameters. Finally, the optimal wave conditions on wind retrieved from ASCAT are determined based on the error analyses. Results show ocean wave parameters have correlative relationships with the RMSE of retrieved wind speed and MAE of retrieved wind direction. The optimal wave conditions are presented in terms of dpd, swh, apd and angle. |
| 中文摘要: |
| 为改善反演效果，本文研究海浪对散射计风场反演精度的影响。首先，收集同步的ASCAT散射计数据和NDBC浮标数据，并将浮标风速统一转换成海面10 m高度风速。其次，比较ASCAT和浮标的风速和风向。再次，利用 ASCAT和浮标风速、风向的误差建立同各种海浪参数的函数关系，来分析海浪对风场反演的影响。涉及海浪参数包括主波波长（dpd）、有效波高（swh）、平均波长（apd）以及主波波向和风向的夹角（angle）。针对误差的计算，先将各种海浪参数分为多个数值区间，再对照各区间将同步数据划分为多个小数据集。通过计算各小数据集的均方根误差（RMSE)和平均绝对误差（MAE），建立误差同各海浪参数的函数关系。最后，基与误差分析方法确定ASCAT风场反演的最佳海浪条件。研究结果表明，海浪参数与反演风速的RMSE以及反演风向的MAE均存在一定的相关关系。最佳海浪条件以dpd，swh，apd和angle的形式提出。 |
|
HTML
Download PDF
View/Add Comment Download reader |
| Close |
|
|
|
