Seasonal transition characteristics of the westerly jet: Study based on field observations at an altitude of 6900 m on the Mt. Xixiabangma Dasuopu glacier

Li, ShengHai; Tian, Lide; Wang, Pengling

doi:10.1007/s11434-011-4508-x

Cited by 17 publications

(20 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The westerly jet with stronger wind speed brings dry and cold air from the Eurasian continent that decreases moisture and causes a reduction in air temperature at higher elevations in this season (e.g. Böhner, ; Li et al , ; Zhou et al , ; Kattel et al , ), which may support the argument. Relatively smaller values of TLRs in winter are observed in December, varying from −9.52 to −10.3 °C km −1 (Table S1), perhaps due to the greater effect of cloud or fog in the day, and at night the effect of radiative cooling on snow‐covered higher‐elevation terrain (Figure (a)) (Kattel et al , ).…”

Section: Resultsmentioning

confidence: 97%

Temperature–topographic elevation relationship for high mountain terrain: an example from the southeastern Tibetan Plateau

Kattel

2018

Intl Journal of Climatology

Self Cite

View full text Add to dashboard Cite

This study quantifies the spatial–temporal distribution of the near‐surface temperature lapse rate (TLR) on the southeastern Tibetan Plateau (SETP) on the northern slopes of the eastern Himalayas, using the jackknife regression model. A 20‐year (1985–2004) climatic data set of 16 stations between the elevation range of 3553–4801 m asl was used for this investigation. Controls for the spatial–temporal variation on TLRs and causes of higher mean square error (MSE) from the jackknife regressions were also analysed. Dry convection due to increasing sensible heating at lower elevations associated with clear skies, the effect of cold air surges, cloud/fog, as well as pronounced long‐wave radiation loss due to snow cover at higher elevation, results in the super‐dry adiabatic TLR in the dry winter. In response to the effects of high rainfall and humidity, intense latent heating at higher elevation due to moist adiabatic cooling causes TLRs to decrease significantly in summer. The variation in net radiation due to differences in moisture, rainfall, cloud cover and air mass between higher (fewer) and lower (higher) elevations further contributes to reducing TLRs values in this season. Observed steeper values of TLRs at higher elevations and more shallow values at lower elevations are due to the thermal contrast between snow‐free ground and snow‐covered mountain terrain, as well as the effect of variations in air mass and moisture. Based on derived values, this article also estimates near‐surface temperature at higher elevations and analyses the precision of estimated values. Measurement of the lowest discrepancy (bias) between observed and estimated values from this study suggests that the estimation skills of the model are good enough. More precisely, including the smallest MSE from the jackknife regression and biases of the estimated values can be made for summer, perhaps due to the moisture controlled throughout the SETP, i.e. associated with the Indian monsoon. Higher MSE and biases are observed during winter and are due to the substantial effects of westerlies, as well as the station's geographical coordinate, local topography and microclimate. The MSE and the estimated biases are lowest at high‐elevation stations and are associated with the lower contaminating effects of the surface. This estimation model, using derived values from this investigation, could be useful for glacier‐hydro‐climatic and ecological modelling in this region.

show abstract

Section: Resultsmentioning

confidence: 97%

Temperature–topographic elevation relationship for high mountain terrain: an example from the southeastern Tibetan Plateau

Kattel

2018

Intl Journal of Climatology

Self Cite

View full text Add to dashboard Cite

show abstract

“…The loss of long wave radiation may be responsible for strong cooling during the daytime in snow covered regions (McClung and Schaerer, 2006) that strengthens the maximum TLR in January. Furthermore, strong wind speed and direction (cold and dry air laden) with higher variability recorded in the same month by Li et al (2011) might be an additional factor for further steepening the TLR during daytime in SETP.…”

Section: Controlling Factors Of Tlr During Wintermentioning

confidence: 99%

Comparison of temperature lapse rates from the northern to the southern slopes of the Himalayas

Kattel

Yao

Yang

et al. 2015

Intl Journal of Climatology

Self Cite

View full text Add to dashboard Cite

Based on 20-year (1985Based on 20-year ( -2004 records of surface-air-temperature at 16 stations between the elevations of 3553 m and 4801 m a.s.l. in the southeastern Tibetan Plateau (or the northern slopes of the eastern Himalayas), this paper examines the monthly, seasonal and annual characteristics of near-surface temperature lapse rates (TLRs). A linear regression model was fitted for the lapse rate calculation. The annual cycle of the TLR shows a distinct seasonal pattern, i.e. steepest in winter and shallowest in summer. Results are partially consistent with those from the southern slopes of the central Himalayas, in particular in summer, and correspond to the warm, rainy and humid season. In response to the monsoonal effect, the released latent heat of water vapour condensation causes an increase in air temperature at higher elevations. Therefore, the TLR is shallowest in the summer. The considerable amount of solar radiation at higher elevations also causes a reduction of the TLR in this season. The lowest diurnal range of lapse rates for summer is associated with lower diurnal variability in net radiation due to cloud cover and relative humidity. The steepest TLR occurs in winter in association with intense cooling at higher elevations, corresponding to the continental dry and cold air surges, and considerable snow-temperature feedback. Lower insolation, deeper snow cover and a weaker inversion effect cause a lower diurnal range of TLR in this season. The observed contrast of winter TLR from the northern to southern slopes of the Himalayas is due to differences in elevation and topography, as well as the pronounced effect of cold air surges. KEY WORDS temperature lapse rate; seasonal variation; moisture effect; northern and southern slopes; Himalayas

show abstract

“…The corresponding pattern is shown in Figure b (named the “summer pattern”). The northward or southward movements of the westerly jet mainstream has been identified on an orbital and millennial scale in geological records preserved in glaciers and sediments (Li SH et al, ; Nagashima et al, , , ; Dong Z et al, ).…”

Section: Discussionmentioning

confidence: 99%

Changes in diffuse reflectance spectroscopy properties of hematite in sediments from the North Pacific Ocean and implications for eolian dust evolution history

Zhang

Liu

2018

Earth and Planetary Physics

View full text Add to dashboard Cite

Eolian dust preserved in deep‐sea sediments of the North Pacific Ocean (NPO) is an important recorder of paleoclimatic and paleoenvironmental changes in the Asian inland. To better understand changes in the dust provenances, in this study diffuse reflectance spectroscopy (DRS) was used to extract the eolian signal recorded in sediments of ODP Hole 885A recovered from the NPO. First, we systematically investigated sieving effects on the DRS data; then band positions of hematite (obtained from the second order derivative curves of the K‐M remission function spectrum derived from the DRS) were used to distinguish different provenances of the eolian dust preserved in the pelagic sediments of this hole. Our results show that the sieving (38 μm) process can suppress effectively the experimental errors. Eolian signatures from Chinese Loess Plateau (CLP) sources and non‐CLP‐sources have been identified in the pelagic sediments of ODP Hole 885A from the late Pliocene to the early Pleistocene. The provenance differences account for the discrepancies in the eolian records recovered from the pelagic sediments in the NPO and profiles in the CLP. Temporal changes in dust provenances are caused by the latitudinal movement of the westerly jet mainstream. The hematite DRS band position is a useful tool to distinguish the provenance of eolian components preserved in pelagic sediments.

show abstract

Seasonal transition characteristics of the westerly jet: Study based on field observations at an altitude of 6900 m on the Mt. Xixiabangma Dasuopu glacier

Cited by 17 publications

References 15 publications

Temperature–topographic elevation relationship for high mountain terrain: an example from the southeastern Tibetan Plateau

Temperature–topographic elevation relationship for high mountain terrain: an example from the southeastern Tibetan Plateau

Comparison of temperature lapse rates from the northern to the southern slopes of the Himalayas

Changes in diffuse reflectance spectroscopy properties of hematite in sediments from the North Pacific Ocean and implications for eolian dust evolution history

Contact Info

Product

Resources

About