Intensifying tropical cyclones over the North Indian Ocean during summer monsoon—Global warming

Krishna, K. Muni

doi:10.1016/j.gloplacha.2008.10.007

Cited by 73 publications

(38 citation statements)

References 31 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The increase in the frequency of extreme events can be associated with more warming of equatorial Indian Ocean than northern latitudes of the tropics that reduced vertical wind shear over the northern Indian Ocean and is thus responsible for the intensified activity of the strongest cyclones (Elsner et al 2008;Krishna 2009). However, a significant reduction of moderate rain events can be the effect of the weakening of the summer monsoon circulation related to the reduction of the strength of the wind field over peninsular India and the adjoining southern parts of the Bay of Bengal in the second half of the twentieth century (Dash et al 2009).…”

Section: Monsoonmentioning

confidence: 99%

Variation in the orographic extreme rain events over the Meghalaya Hills in northeast India in the two halves of the twentieth century

Prokop

Walanus

2014

Theor Appl Climatol

View full text Add to dashboard Cite

The daily rainfall data for the twentieth century, from three stations across the region, constitute the basis for statistical analysis. However, the low signal-to-noise ratio makes it difficult to find any significant departure from the simplest null hypothesis of the stability of the rain record at individual stations in northeast India. Only the coarsest possible view, i.e. comparing the two halves of the century, provided strongly significant results in the numbers of days with extreme rain. Using a more general approach, the number of Fourier transform extreme amplitudes also differed significantly. Increasingly heavy events during the summer monsoon season, and partly in the pre-and post-monsoon seasons, are offset by a weakening in the winter monsoon season, so that the annual mean rainfall does not show a significant trend over the Meghalaya Hills. Apart from a greater number of years with noticeable extreme rainfall events in the second half of the twentieth century, we can also observe a more pronounced quasi-periodicity of 10-20 and 30-60 days during the same period. The detection of the latter periodicity indicates that the Madden-Julian oscillation plays an important role in the formation of extreme rainfall events over the Meghalaya Hills during extreme monsoon years.

show abstract

Section: Monsoonmentioning

confidence: 99%

Variation in the orographic extreme rain events over the Meghalaya Hills in northeast India in the two halves of the twentieth century

Prokop

Walanus

2014

Theor Appl Climatol

View full text Add to dashboard Cite

show abstract

“…The strength of the vertical wind shear over the Arabian Sea is dependent on the strength of the Indian summer monsoon and the tropical easterly jet higher up in the atmosphere. The high-altitude winds flow from the opposite direction of the low-level monsoon winds creating a high vertical wind shear, which halts cyclone formation by blowing off the top of tropical storms (Hubert et al, 1983;Rao et al, 2008;Krishna, 2009) because it is coupled to a decrease of the vertical wind shear (Rao et al, 2008;. The Indian monsoon is an integral part of the Asian monsoon system.…”

Section: Vertical Wind Shearmentioning

confidence: 99%

Cyclone trends constrain monsoon variability during late Oligocene sea level highstands (Kachchh Basin, NW India)

et al. 2013

View full text Add to dashboard Cite

Climate change has an unknown impact on tropical cyclones and the Asian monsoon. Herein we present a sequence of fossil shell beds from the shallow-marine Maniyara Fort Formation (Kachcch Basin) as a recorder of tropical cyclone activity along the NW Indian coast during the late Oligocene warming period (~ 27–24 Ma). Proxy data providing information about the atmospheric circulation dynamics over the Indian subcontinent at this time are important since it corresponds to a major climate reorganization in Asia that ends up with the establishment of the modern Asian monsoon system at the Oligocene–Miocene boundary. The vast shell concentrations are comprised of a mixture of parautochthonous and allochthonous assemblages indicating storm-generated sediment transport from deeper to shallow water during third-order sea level highstands. Three distinct skeletal assemblages were distinguished, each recording a relative storm wave base. (1) A shallow storm wave base is shown by nearshore molluscs, reef corals and Clypeaster echinoids; (2) an intermediate storm wave base depth is indicated by lepidocyclinid foraminifers, Eupatagus echinoids and corallinacean algae; and (3) a deep storm wave base is represented by an Amussiopecten bivalve-Schizaster echinoid assemblage. These wave base depth estimates were used for the reconstruction of long-term tropical storm intensity during the late Oligocene. The development and intensification of cyclones over the recent Arabian Sea is primarily limited by the atmospheric monsoon circulation and strength of the associated vertical wind shear. Therefore, since the topographic boundary conditions for the Indian monsoon already existed in the late Oligocene, the reconstructed long-term cyclone trends were interpreted to reflect monsoon variability during the initiation of the Asian monsoon system. Our results imply an active monsoon over the Eastern Tethys at ~ 26 Ma followed by a period of monsoon weakening during the peak of the late Oligocene global warming (~ 24 Ma)

show abstract

“…No intense cyclones were observed during the July to September quarter between 1980 and 2009. In fact, maps produced by the University of Wisconsin show that this period, corresponding to the middle of the monsoon season, is characterized by a strong vertical wind shear preventing storms from becoming intense cyclones (Krishna, 2009). The southwest flows of the lower and middle troposphere are crowned by winds with an easterly component in the upper troposphere.…”

Section: An Atypical But Far From Innocuous Intense Cyclones Activitymentioning

confidence: 99%

Intense tropical cyclone activities in the northern Indian Ocean

Hoarau

Bernard

Chalonge

2011

Intl Journal of Climatology

View full text Add to dashboard Cite

This research concerning the northern Indian Ocean demonstrates the variability of intense tropical cyclones (categories 3-5) both on an inter-annual and intra-seasonal scale. All the cyclones intensity have been re-analysed with the Dvorak technique using both National Oceanic and Atmospheric Administration and geostationary satellites with a 4-km infrared resolution. During the period from 1980 to 2009, 21 cyclones became intense. The decade from 1990 to 1999 was by far the most active with 11 intense cyclones while 5 intense cyclones formed in each of the other two decades. There has been no trend towards an increase in the number of categories 3-5 cyclones over the last 30 years. An early study, not based on re-analysed data, found a significant increase in the number of intense cyclones. Thirteen cyclones became intense when the Oceanic Nino Index was negative and matched with lower vertical wind shear. And, La Nina events have had a noticeable influence with eight intense cyclones. The monthly distribution is bimodal with seven and eight cyclones, respectively in the months of May and November. No intense cyclones were observed from July to September, being the peak of the monsoon season. Over these 3 months, the vertical wind shear is too strong to allow a significant intensification of storms. Despite particularly warm ocean waters, only 6% of categories 1-5 cyclones approached their maximum potential intensity. However, extreme intensities (05B at 155 knots in 1999) are comparable to other basins despite lower in terms of activity level. The proximity of land limits most cyclones from reaching a greater intensity. However, 16 of the 21 cyclones reached land with sustained winds of 100 knots and more. India and Bangladesh have been hit frequently by intense cyclones. Since 1990s, there is an increasing hit in Burma and Pakistan.

show abstract

Intensifying tropical cyclones over the North Indian Ocean during summer monsoon—Global warming

Cited by 73 publications

References 31 publications

Variation in the orographic extreme rain events over the Meghalaya Hills in northeast India in the two halves of the twentieth century

Variation in the orographic extreme rain events over the Meghalaya Hills in northeast India in the two halves of the twentieth century

Cyclone trends constrain monsoon variability during late Oligocene sea level highstands (Kachchh Basin, NW India)

Intense tropical cyclone activities in the northern Indian Ocean

Contact Info

Product

Resources

About