从雷达垂直风观测数据看热带UTLS的高频重力波和开尔文-赫姆霍兹气流

IF 4.6 1区 地球科学 Q1 GEOSCIENCES, MULTIDISCIPLINARY
Ajil Kottayil, Aurélien Podglajen, Bernard Legras, Rachel Atlas, Prajwal K, K. Satheesan, Abhilash S
{"title":"从雷达垂直风观测数据看热带UTLS的高频重力波和开尔文-赫姆霍兹气流","authors":"Ajil Kottayil,&nbsp;Aurélien Podglajen,&nbsp;Bernard Legras,&nbsp;Rachel Atlas,&nbsp;Prajwal K,&nbsp;K. Satheesan,&nbsp;Abhilash S","doi":"10.1029/2024GL110366","DOIUrl":null,"url":null,"abstract":"<p>The present study analyzes novel observations of vertical wind <span></span><math>\n <semantics>\n <mrow>\n <mo>(</mo>\n <mi>w</mi>\n <mo>)</mo>\n </mrow>\n <annotation> $(w)$</annotation>\n </semantics></math> in the tropical upper troposphere-lower stratosphere obtained from a radar wind profiler in Cochin, India. Between December 2022 and April 2023, 63 consecutive 4 hr curtains of <span></span><math>\n <semantics>\n <mrow>\n <mi>w</mi>\n </mrow>\n <annotation> $w$</annotation>\n </semantics></math> were measured with a vertical spacing of 180 m and a sampling time step of 44 s, thus resolving almost the whole spectrum of vertical motions. Spectra of <span></span><math>\n <semantics>\n <mrow>\n <mi>w</mi>\n </mrow>\n <annotation> $w$</annotation>\n </semantics></math> strongly vary with altitude. They are generally flat up to the local Brunt-Väisälä frequency (BVF), but sometimes exhibit a peak of <span></span><math>\n <semantics>\n <mrow>\n <mi>w</mi>\n </mrow>\n <annotation> $w$</annotation>\n </semantics></math> variance closer to BVF, a feature which may be attributed to trapped gravity waves. At other times and locations, the <span></span><math>\n <semantics>\n <mrow>\n <mi>w</mi>\n </mrow>\n <annotation> $w$</annotation>\n </semantics></math> profiles reveal Kelvin-Helmholtz billows. Finally, the variability of <span></span><math>\n <semantics>\n <mrow>\n <mi>w</mi>\n </mrow>\n <annotation> $w$</annotation>\n </semantics></math> variance over the 4 month campaign period is investigated. Using brightness temperature from geostationary satellites as a convective proxy, it is found that <span></span><math>\n <semantics>\n <mrow>\n <mi>w</mi>\n </mrow>\n <annotation> $w$</annotation>\n </semantics></math> variance is highly correlated with fluctuations in convective activity.</p>","PeriodicalId":12523,"journal":{"name":"Geophysical Research Letters","volume":"51 21","pages":""},"PeriodicalIF":4.6000,"publicationDate":"2024-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024GL110366","citationCount":"0","resultStr":"{\"title\":\"High-Frequency Gravity Waves and Kelvin-Helmholtz Billows in the Tropical UTLS, as Seen From Radar Observations of Vertical Wind\",\"authors\":\"Ajil Kottayil,&nbsp;Aurélien Podglajen,&nbsp;Bernard Legras,&nbsp;Rachel Atlas,&nbsp;Prajwal K,&nbsp;K. Satheesan,&nbsp;Abhilash S\",\"doi\":\"10.1029/2024GL110366\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p>The present study analyzes novel observations of vertical wind <span></span><math>\\n <semantics>\\n <mrow>\\n <mo>(</mo>\\n <mi>w</mi>\\n <mo>)</mo>\\n </mrow>\\n <annotation> $(w)$</annotation>\\n </semantics></math> in the tropical upper troposphere-lower stratosphere obtained from a radar wind profiler in Cochin, India. Between December 2022 and April 2023, 63 consecutive 4 hr curtains of <span></span><math>\\n <semantics>\\n <mrow>\\n <mi>w</mi>\\n </mrow>\\n <annotation> $w$</annotation>\\n </semantics></math> were measured with a vertical spacing of 180 m and a sampling time step of 44 s, thus resolving almost the whole spectrum of vertical motions. Spectra of <span></span><math>\\n <semantics>\\n <mrow>\\n <mi>w</mi>\\n </mrow>\\n <annotation> $w$</annotation>\\n </semantics></math> strongly vary with altitude. They are generally flat up to the local Brunt-Väisälä frequency (BVF), but sometimes exhibit a peak of <span></span><math>\\n <semantics>\\n <mrow>\\n <mi>w</mi>\\n </mrow>\\n <annotation> $w$</annotation>\\n </semantics></math> variance closer to BVF, a feature which may be attributed to trapped gravity waves. At other times and locations, the <span></span><math>\\n <semantics>\\n <mrow>\\n <mi>w</mi>\\n </mrow>\\n <annotation> $w$</annotation>\\n </semantics></math> profiles reveal Kelvin-Helmholtz billows. Finally, the variability of <span></span><math>\\n <semantics>\\n <mrow>\\n <mi>w</mi>\\n </mrow>\\n <annotation> $w$</annotation>\\n </semantics></math> variance over the 4 month campaign period is investigated. Using brightness temperature from geostationary satellites as a convective proxy, it is found that <span></span><math>\\n <semantics>\\n <mrow>\\n <mi>w</mi>\\n </mrow>\\n <annotation> $w$</annotation>\\n </semantics></math> variance is highly correlated with fluctuations in convective activity.</p>\",\"PeriodicalId\":12523,\"journal\":{\"name\":\"Geophysical Research Letters\",\"volume\":\"51 21\",\"pages\":\"\"},\"PeriodicalIF\":4.6000,\"publicationDate\":\"2024-11-08\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024GL110366\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Geophysical Research Letters\",\"FirstCategoryId\":\"89\",\"ListUrlMain\":\"https://onlinelibrary.wiley.com/doi/10.1029/2024GL110366\",\"RegionNum\":1,\"RegionCategory\":\"地球科学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"GEOSCIENCES, MULTIDISCIPLINARY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Geophysical Research Letters","FirstCategoryId":"89","ListUrlMain":"https://onlinelibrary.wiley.com/doi/10.1029/2024GL110366","RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"GEOSCIENCES, MULTIDISCIPLINARY","Score":null,"Total":0}
引用次数: 0

摘要

本研究分析了从印度科钦的雷达风廓线仪获得的热带对流层上部-平流层下部垂直风(w)$(w)$的新观测数据。在 2022 年 12 月至 2023 年 4 月期间,以 180 米的垂直间距和 44 秒的采样时间步长测量了 63 个连续 4 小时的 w$w$ 窗帘,从而解析了几乎整个垂直运动频谱。w$w$ 的频谱随高度变化很大。一般来说,直到当地的布伦特-韦赛莱频率(BVF)都是平的,但有时会在更接近布伦特-韦赛莱频率的地方出现 w$w$ 方差峰值,这可能是受困重力波造成的。在其他时间和地点,w$w$剖面显示出开尔文-赫尔姆霍兹波浪。最后,研究了 w$w$ 方差在 4 个月活动期间的变化情况。利用地球静止卫星的亮度温度作为对流的代用指标,发现 w$w$ 方差与对流活动的波动高度相关。
本文章由计算机程序翻译,如有差异,请以英文原文为准。

High-Frequency Gravity Waves and Kelvin-Helmholtz Billows in the Tropical UTLS, as Seen From Radar Observations of Vertical Wind

High-Frequency Gravity Waves and Kelvin-Helmholtz Billows in the Tropical UTLS, as Seen From Radar Observations of Vertical Wind

The present study analyzes novel observations of vertical wind ( w ) $(w)$ in the tropical upper troposphere-lower stratosphere obtained from a radar wind profiler in Cochin, India. Between December 2022 and April 2023, 63 consecutive 4 hr curtains of w $w$ were measured with a vertical spacing of 180 m and a sampling time step of 44 s, thus resolving almost the whole spectrum of vertical motions. Spectra of w $w$ strongly vary with altitude. They are generally flat up to the local Brunt-Väisälä frequency (BVF), but sometimes exhibit a peak of w $w$ variance closer to BVF, a feature which may be attributed to trapped gravity waves. At other times and locations, the w $w$ profiles reveal Kelvin-Helmholtz billows. Finally, the variability of w $w$ variance over the 4 month campaign period is investigated. Using brightness temperature from geostationary satellites as a convective proxy, it is found that w $w$ variance is highly correlated with fluctuations in convective activity.

求助全文
通过发布文献求助,成功后即可免费获取论文全文。 去求助
来源期刊
Geophysical Research Letters
Geophysical Research Letters 地学-地球科学综合
CiteScore
9.00
自引率
9.60%
发文量
1588
审稿时长
2.2 months
期刊介绍: Geophysical Research Letters (GRL) publishes high-impact, innovative, and timely research on major scientific advances in all the major geoscience disciplines. Papers are communications-length articles and should have broad and immediate implications in their discipline or across the geosciences. GRLmaintains the fastest turn-around of all high-impact publications in the geosciences and works closely with authors to ensure broad visibility of top papers.
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
确定
请完成安全验证×
copy
已复制链接
快去分享给好友吧!
我知道了
右上角分享
点击右上角分享
0
联系我们:info@booksci.cn Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。 Copyright © 2023 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术官方微信