Excitation of low-level jet as seen by GOES (I-O) satellite off the Somali coast

Mahajan, P. N.; Mupmdar, V. R.; Ghanekar, S. P.

doi:10.1007/bf02659081

Cited by 4 publications

(2 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Aside from cloud motion vector and scatterometer methods to detect LLJs over oceans (Chelton et al, 2000;Garreaud & Muñoz, 2005;Mahajan et al, 1989), satellite observations of LLJs are less common. Over land, one approach to identifying and quantifying LLJ winds has been to track plumes observed in high-resolution satellite overpasses (Koren & Kaufman, 2004;Todd et al, 2008).…”

Section: Low-level Jetsmentioning

confidence: 99%

A 14‐Year Climatology of Saharan Dust Emission Mechanisms Inferred From Automatically Tracked Plumes

2019

View full text Add to dashboard Cite

The central and western Sahara is the largest source of mineral aerosols during boreal summer, but observed ground‐based data are extremely scarce and typically distant from key source regions. Knowledge of dust emission mechanisms has therefore been mostly limited to short‐term observations from a point or model approximations. To address this deficiency, dust plumes from the central and western Sahara are classified according to emission mechanism for June, July, and August of 2004–2017 using an automated inference method, which accurately tracks the timing, convective association, and geometry of plumes observed with the Spinning Enhanced Visible and Infrared Imager aboard Meteosat Second Generation satellites. From these characteristics, plumes are classified as either low‐level jet or cold pool outflow events. The extensive data set is used to generate the largest available climatology of dust emission sources and Saharan emission mechanisms. Automated inference compares well with ground‐based measurements from the Fennec Campaign (76% accuracy) as well as with an entirely manual approach (88% accuracy). Cold pool activity accounts for 82% of total observed dust and 88% at the point of emission. Dust from cold pools evolves seasonally from hot spots around the Mali‐Niger‐Algeria border triple point toward the central Sahara to the northwest, while dust from low‐level jets is organized along the axis of the northeasterly Harmattan, and dominates emission within the Tidihelt Depression of central Algeria. The widespread importance of cold pool outflows in this research supports the findings of the Fennec Campaign, but low‐level jets remain highly significant in certain isolated hot spots.

show abstract

Section: Low-level Jetsmentioning

confidence: 99%

A 14‐Year Climatology of Saharan Dust Emission Mechanisms Inferred From Automatically Tracked Plumes

2019

View full text Add to dashboard Cite

show abstract

“…During the period of the Indian summer monsoon season, strong heat troughs form over land areas surrounding the Arabian Sea, particularly over areas of north India, Pakistan, Iran and Saudi Arabia. At the same time, high mountains like Himalaya, to the north, seal off the cold air outbreaks (Mahajan et al, 1989). In the past, the relationship between tropospheric temperature in pre-monsoon months and the Indian summer monsoon rainfall (ISMR: June to September total rainfall) has been examined in several studies (Verma, 1982;Mooley and Paolino, 1988;Parthasarathy et al, 1990;Rajeevan et al, 1998;Kothawale and Rupa Kumar, 2002).…”

Section: Introductionmentioning

confidence: 99%

Association of the pre-monsoon thermal field over north India and the western Tibetan Plateau with summer monsoon rainfall over India

Bansod

Ghanekar²

2015

Ann. Geophys.

Self Cite

View full text Add to dashboard Cite

Abstract. In this paper, interannual variability of tropospheric air temperatures over the Asian summer monsoon region during the pre-monsoon months is examined in relation to Indian summer monsoon rainfall (ISMR; June to September total rainfall). For this purpose, monthly gridpoint temperatures in the entire troposphere over the Asian summer monsoon region and ISMR data for the period 1949-2012 have been used. Spatial correlation patterns are investigated between the temperature field in the lower tropospheric levels during May over the Asian summer monsoon region and ISMR. The results indicate a strong and significant northwest-southeast dipole structure in the spatial correlations over the Indian region, with highly significant positive (negative) correlations over the regions of north India and the western Tibetan Plateau region -region R1 (north Bay of Bengal: region R2). The observed dipole is seen significantly up to a level of 850 hPa and eventually disappears at 700 hPa. Thermal indices evaluated at 850 hPa level, based on average air temperatures over the north India and western Tibetan Plateau region (TI 1 ) and the north Bay of Bengal region (TI 2 ) during May, show a strong, significant relationship with the ISMR. The results are found to be consistent and robust, especially in the case of TI 1 during the period of analysis. A physical mechanism for the relationship between these indices and ISMR is proposed. Finally the composite annual cycle of tropospheric air temperature over R1 during flood/drought years of ISMR is examined. The study brings out the importance of the TI 1 in the prediction of flood/drought conditions over the Indian subcontinent.

show abstract

Use of INSAT winds for better depiction of monsoon depressions over the Indian region

Mahajan

Talwalkar

Chinthalu

et al. 1995

Meteorological Applications

View full text Add to dashboard Cite

show abstract

Excitation of low-level jet as seen by GOES (I-O) satellite off the Somali coast

Cited by 4 publications

References 11 publications

A 14‐Year Climatology of Saharan Dust Emission Mechanisms Inferred From Automatically Tracked Plumes

A 14‐Year Climatology of Saharan Dust Emission Mechanisms Inferred From Automatically Tracked Plumes

Association of the pre-monsoon thermal field over north India and the western Tibetan Plateau with summer monsoon rainfall over India

Use of INSAT winds for better depiction of monsoon depressions over the Indian region

Contact Info

Product

Resources

About