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Highest Mountain (highest + mountain)

Distribution by Scientific Domains
Life Sciences33%
Humanities and Social Sciences33%
Earth and Environmental Science33%

Selected Abstracts

Climate change-driven forest fires marginalize the impact of ice cap wasting on Kilimanjaro

GLOBAL CHANGE BIOLOGY, Issue 7 2005
Andreas Hemp
Abstract The disappearing glaciers of Kilimanjaro are attracting broad interest. Less conspicuous but ecologically far more significant is the associated increase of frequency and intensity of fires on the slopes of Kilimanjaro, which leads to a downward shift of the upper forest line by several hundred meters as a result of a drier (warmer) climate since the last century. In contrast to common belief, global warming does not necessarily cause upward migration of plants and animals. Here, it is shown that on Kilimanjaro the opposite trend is under way, with consequences more harmful than those due to the loss of the showy ice cap of Africa's highest mountain. [source]

Mass balance of a slope glacier on Kilimanjaro and its sensitivity to climate

INTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 7 2008
Thomas Mölg
Abstract Meteorological and glaciological measurements obtained at 5873 m a.s.l. on Kersten Glacier, a slope glacier on the southern flanks of Kilimanjaro, are used to run a physically-based mass balance model for the period February 2005 to January 2006. This shows that net shortwave radiation is the most variable energy flux at the glacier-atmosphere interface, governed by surface albedo. The majority of the mass loss (,65%) is due to sublimation (direct conversion of snow/ice to water vapour), with melting of secondary importance. Sensitivity experiments reveal that glacier mass balance is 2,4 times more sensitive to a 20% precipitation change than to a 1 °C air temperature change. These figures also hold when the model is run with input data representative of a longer term (1979,2004) mean period. Results suggest that a regional-scale moisture projection for the 21st century is crucial to a physically-based prediction of glacier retention on Africa's highest mountain. Copyright © 2007 Royal Meteorological Society [source]

Climate change and its impact on the forests of Kilimanjaro

AFRICAN JOURNAL OF ECOLOGY, Issue 2009
Andreas Hemp
Abstract Cloud forests are of great importance in the hydrological functioning of watersheds in subhumid East Africa. However, the montane forests of Mt. Kilimanjaro are heavily threatened by global change impacts. Based on an evaluation of over 1500 vegetation plots and interpretation of satellite imagery from 1976 and 2000, land-cover changes on Kilimanjaro were evaluated and their impact on the water balance estimated. While the vanishing glaciers of Kilimanjaro attract broad interest, the associated increase of frequency and intensity of fires on the slopes of Kilimanjaro is less conspicuous but ecologically far more significant. These climate change-induced fires have lead to changes in species composition and structure of the forests and to a downward shift of the upper forest line by several hundred metres. During the last 70 years, Kilimanjaro has lost nearly one-third of its forest cover, in the upper areas caused by fire, on the lower forest border mainly caused by clearing. The loss of 150 km2 of cloud forest , the most effective source in the upper montane and subalpine fog interception zone , caused by fire during the last three decades means a considerable reduction in water yield. In contrast to common belief, global warming does not necessarily cause upward migration of plants and animals. On Kilimanjaro the opposite trend is under way, with consequences more harmful than those due to the loss of the showy ice cap of Africa's highest mountain. [source]

The Importance of Deviance in Intellectual Development

AMERICAN JOURNAL OF ECONOMICS AND SOCIOLOGY, Issue 1 2004
Especially at Virginia Tech in the 1970s
This paper seeks to explain the success of public choice at Virginia Tech in the 1970s in two ways. First, I reflect on my graduate school experience at Virginia Tech, with the intent of identifying particular characteristics of the people and location of Virginia Tech, including its remoteness, that facilitated the development of the paradigm shift that public choice, in the late 1960s and early 1970s, represented. Second, I argue that the success of public choice at Virginia Tech depended critically upon the willingness of the people here to disconnect from professional constraints and to think outside the conventional economics box. I make this point with the aid of a computer simulation of the evolutionary development of "people" (or "trials") as they attempt to scale the highest "mountain" within a "mountain range," the exact features of which (including the heights of the various "mountains") are not known before the climb is started. In such an environment, finding the highest peak, the assumed goal, is critically dependent on a measure of "deviance," or the willingness to shun short-run opportunities of exploiting accepted methods. [source]

The Donegal ice dome, northwest Ireland: dimensions and chronology,

JOURNAL OF QUATERNARY SCIENCE, Issue 8 2007
Colin K. Ballantyne
Abstract Geomorphological evidence indicates that Donegal was formerly occupied by an ice dome that extended offshore to the west, northwest and north and was confluent with adjacent ice masses to the east and south. Erosive warm-based ice over-rode almost all the highest mountains, implying an ice-divide altitude greater than 700,m. Only six peripheral summits escaped glacial modification, implying either that they remained above the ice surface as nunataks or supported a thin cover of protective cold-based ice. Gibbsite, a pre-last glacial weathering product, is preferentially represented on summits that escaped glacial modification. Cosmogenic 10Be exposure ages of 18.6,±,1.4 to 15.9,±,1.0,k yr for coastal sites confirm that Donegal ice extended offshore at the last glacial maximum. Reconstruction of the form of the Donegal ice dome suggests a former minimum ice thickness of ,500,m close to the present coastline in the west and northwest, and ,400,m near the coast of the Inishowen Peninsula in the north, with the ice extending at least 20,km across the adjacent shelf to the west and northwest. Copyright © 2007 John Wiley & Sons, Ltd. [source]

Föhn as a response to changing upstream and downstream air masses

THE QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, Issue 635 2008
Georg J. Mayr
Abstract Observations of föhn from the field phase of the Mesoscale Alpine Programme (MAP) are used to study how differences between the air masses upstream and downstream of the central Alpine crest determine whether the flow can descend to the lee as either shallow föhn, when it passes through passes in the mountains, or deep föhn, when it overflows the Alpine crest. First, the föhn case of 30 October 1999 is examined using ECMWF analyses and radiosonde data at various upstream and downstream locations. Additional measurements from aircraft, dropsondes, an instrumented car and automatic weather stations are then used for a detailed study of the föhn flow across the Brenner Pass. Advection of cold air around the eastern edges of the Alps and warm air around the western edge of the Alps ahead of a synoptic ridge set up a reservoir of colder air on the south side of the Alps and a reservoir of warmer air to the north. The depth to where the air was colder on the southern side was sufficient for a shallow föhn to flow through the pass. After the passage of the ridge axis, synoptic cold air advection provided another source of colder air, this time from the southwest, growing deeper with time and having a synoptically imposed cross-barrier flow component. The maximum depth to where the air upstream was colder than downstream extended just above the peaks of the highest mountains. An analysis of the detailed measurements across the Brenner Pass showed that this depth was also the top of the layer that descended and accelerated down the lee slopes of the Wipp Valley. Upstream, air above the föhn layer had an even stronger cross-barrier component yet did not descend because it did not have lower potential temperatures than the downstream side at that level. Deep föhn never developed. An examination of other well-documented MAP föhn cases confirmed the conclusion from the 30 October event that shallow and deep föhns , at least for the central Alps , are mostly a response to differences in air masses between the upstream and downstream side. A cross-barrier component of the flow was only a modification but in itself not sufficient to cause the flow to both descend and accelerate down the lee slope, unless potential temperatures on the upstream side were lower in this layer than on the downstream side. Copyright © 2008 Royal Meteorological Society [source]