scholarly journals Temperature Measurements at a Cirque Bergschrund in Baffin Island: Some Results of W. R. B. Battle’s Work in 1953

1956 ◽  
Vol 2 (20) ◽  
pp. 762-769 ◽  
Author(s):  
H. R. Thompson ◽  
B. H. Bonnlander
Keyword(s):  
Air Temperature ◽  
Direct Relationship ◽  
Granite Gneiss ◽  
Water Source ◽  
Temperature Measurements ◽  
Baffin Island ◽  
Air Temperatures ◽  
Melt Water

AbstractThermograph, thermistor, and thermometer readings at a 30 m. deep bergschrund from June 6 to July 22, 1953, showed that there was little direct relationship between air temperatures outside and at the bottom of the Schrund. The air temperature inside ranged from −3.7° C. (253° F.) to +0.5° C. (32.9° F.), but from July 2 onwards it oscillated between –0.5° C. and +0.5° C., with a 3–4 day periodicity. The ice temperature at the bottom of the schrund behaved similarly, though it was about 0.5° C. colder. The oscillations may have been caused by the interplay of flowing melt water (source of heat) and air drainage in quiet weather (source of cold). The granite-gneiss headwall, where not sheathed by refrozen melt water, appeared to be chemically and mechanically unweathered, which supported the conclusions of Battle’s earlier tests in deep bergschrunds and in the laboratory.

scholarly journals Temperature Measurements at a Cirque Bergschrund in Baffin Island: Some Results of W. R. B. Battle’s Work in 1953

1956 ◽  
Vol 2 (20) ◽  
pp. 762-769 ◽  
Author(s):  
H. R. Thompson ◽  
B. H. Bonnlander
Keyword(s):  
Air Temperature ◽  
Direct Relationship ◽  
Granite Gneiss ◽  
Water Source ◽  
Temperature Measurements ◽  
Baffin Island ◽  
Air Temperatures ◽  
Melt Water

AbstractThermograph, thermistor, and thermometer readings at a 30 m. deep bergschrund from June 6 to July 22, 1953, showed that there was little direct relationship between air temperatures outside and at the bottom of the Schrund. The air temperature inside ranged from −3.7° C. (253° F.) to +0.5° C. (32.9° F.), but from July 2 onwards it oscillated between –0.5° C. and +0.5° C., with a 3–4 day periodicity. The ice temperature at the bottom of the schrund behaved similarly, though it was about 0.5° C. colder. The oscillations may have been caused by the interplay of flowing melt water (source of heat) and air drainage in quiet weather (source of cold). The granite-gneiss headwall, where not sheathed by refrozen melt water, appeared to be chemically and mechanically unweathered, which supported the conclusions of Battle’s earlier tests in deep bergschrunds and in the laboratory.

Soil and air temperatures during prescribed cerated fires in Central Brazil

1993 ◽  
Vol 9 (3) ◽  
pp. 313-320 ◽  
Author(s):  
Antonio Carlos Miranda ◽  
Heloisa Sinátora Miranda ◽  
Inês de Fátima Oliveira Dias ◽  
Braulio Ferreira de Souza Dias
Keyword(s):  
Air Temperature ◽  
Sensu Stricto ◽  
Temperature Measurements ◽  
Fuel Load ◽  
Native Vegetation ◽  
Central Brazil ◽  
Type K ◽  
Air Temperatures ◽  
Soil Temperatures ◽  
Recorded Data

ABSTRACTAir and soil temperatures were measured during dry season heading fires in three different physiognomic forms of native vegetation common in Central Brazil: cerrado sensu stricto (dense scrub of shrubs and trees), campo cerrado (open scrub), and campo sujo (open grassland with scattered shrubs). The vegetation was protected from fire for 15 y in some areas, had been burned once every two years, and once each year in other areas. The temperatures were measured with type-k thermocouples and recorded at intervals of 22.5 sees. Air temperature measurements were taken at 1, 60 and 160 cm. Maximum air temperatures ranged from 85°C to 840°C, and the duration above 60°C varied from 20 to 270 seconds. In the soil, negligible temperature increases were recorded below 5 cm depth, whereas at 2 cm maximum soil temperatures varied from 29 to 38°C. Possible influences of fuel load and moisture on the recorded data and on the behaviour of fire in the cerrado ecosystems are discussed.

scholarly journals Fiber optic distributed temperature sensing for the determination of air temperature

2015 ◽  
Vol 8 (1) ◽  
pp. 335-339 ◽  
Author(s):  
S. A. P. de Jong ◽  
J. D. Slingerland ◽  
N. C. van de Giesen
Keyword(s):  
Air Temperature ◽  
Urban Areas ◽  
Fiber Optic ◽  
Solar Heating ◽  
Temperature Sensing ◽  
Temperature Measurements ◽  
Distributed Temperature Sensing ◽  
Air Temperatures ◽  
Different Diameters

Abstract. This paper describes a method to correct for the effect of solar radiation in atmospheric distributed temperature sensing (DTS) applications. By using two cables with different diameters, one can determine what temperature a zero diameter cable would have. Such a virtual cable would not be affected by solar heating and would take on the temperature of the surrounding air. With two unshielded cable pairs, one black pair and one white pair, good results were obtained given the general consensus that shielding is needed to avoid radiation errors (WMO, 2010). The correlations between standard air temperature measurements and air temperatures derived from both cables of colors had a high correlation coefficient (r2=0.99) and a RMSE of 0.38 °C, compared to a RMSE of 2.40 °C for a 3.0 mm uncorrected black cable. A thin white cable measured temperatures that were close to air temperature measured with a nearby shielded thermometer (RMSE of 0.61 °C). The temperatures were measured along horizontal cables with an eye to temperature measurements in urban areas, but the same method can be applied to any atmospheric DTS measurements, and for profile measurements along towers or with balloons and quadcopters.

scholarly journals Meteorological factors driven glacial till changing and the associated periglacial debris flows in Tianmo Valley, southeast Tibetan Plateau

2016 ◽  
Author(s):  
Mingfeng Deng ◽  
Ningsheng Chen ◽  
Mei Liu
Keyword(s):  
Tibetan Plateau ◽  
Air Temperature ◽  
Debris Flows ◽  
Large Scale ◽  
The Past ◽  
Air Temperatures ◽  
Melt Water ◽  
Glacial Tills ◽  
The Impact

Abstract. Meteorological studies have indicated that high Alpines are strongly affected by climate warming. Periglacial debris flows are more frequent in deglaciated regions. The combination of rainfall and air temperature controls the initiation of periglacial debris flows; and the addition of melt-water due to higher air temperatures enhances the complexity of the triggering mechanism compared to storm-induced debris flows. In south-eastern Tibetan Plateau where temperate glaciers are widely distributed, numerous periglacial debris flows have occurred in the past 100 years, but none had happened in the Tianmo watershed until 2007. In 2007 and 2010, three large-scale debris flows occurred in the Tianmo watershed. In this research, these three debris flow events were chosen to analyze the impact of the annual meteorological conditions: the antecedent air temperature and meteorological triggers. TM images and field measurement of the nearby glacier suggested that a sharp glacier retreat had existed in the previous one or two years preceding the events, which coincided with the spiked annual air temperature. Besides, changing of glacial tills driven by prolonged increase in the air temperature is the prerequisite of periglacial debris flows. Triggers of periglacial debris flows are multiplied and they could be high intensity rainfall as in DF1 and DF3, or continuous percolation of melt-water due to the long term rising air temperatures as in DF2.

On the dynamics of distribution of the American White Butterfly, Hyphantria cunea Drury, 1973 (Lepidoptera, Arctiidae), in Ukraine regarding the annual minimal air temperatures

2018 ◽  
Vol 14 (1) ◽  
pp. 44-57
Author(s):  
S. N. Shumov
Keyword(s):  
Air Temperature ◽  
Annual Reports ◽  
Complete Elimination ◽  
Hyphantria Cunea ◽  
White American ◽  
Gis Technologies ◽  
Data Analyses ◽  
Air Temperatures ◽  
Negative Temperatures

The spatial analysis of distribution and quantity of Hyphantria cunea Drury, 1973 across Ukraine since 1952 till 2016 regarding the values of annual absolute temperatures of ground air is performed using the Gis-technologies. The long-term pest dissemination data (Annual reports…, 1951–1985; Surveys of the distribution of quarantine pests ..., 1986–2017) and meteorological information (Meteorological Yearbooks of air temperature the surface layer of the atmosphere in Ukraine for the period 1951-2016; Branch State of the Hydrometeorological Service at the Central Geophysical Observatory of the Ministry for Emergencies) were used in the present research. The values of boundary negative temperatures of winter diapause of Hyphantria cunea, that unable the development of species’ subsequent generation, are received. Data analyses suggests almost complete elimination of winter diapausing individuals of White American Butterfly (especially pupae) under the air temperature of −32°С. Because of arising questions on the time of action of absolute minimal air temperatures, it is necessary to ascertain the boundary negative temperatures of winter diapause for White American Butterfly. It is also necessary to perform the more detailed research of a corresponding biological material with application to the freezing technics, giving temperature up to −50°С, with the subsequent analysis of the received results by the punched-analysis.

scholarly journals Heatwaves and Summer Urban Heat Islands: A Daily Cycle Approach to Unveil the Urban Thermal Signal Changes in Lisbon, Portugal

Atmosphere ◽  
2021 ◽  
Vol 12 (3) ◽  
pp. 292 ◽  
Author(s):  
Ana Oliveira ◽  
António Lopes ◽  
Ezequiel Correia ◽  
Samuel Niza ◽  
Amílcar Soares
Keyword(s):  
Climate Change ◽  
Air Temperature ◽  
Wind Direction ◽  
Urban Heat Islands ◽  
Daily Cycle ◽  
Local Climate ◽  
Thermal Signal ◽  
Air Temperatures ◽  
Local Climate Change ◽  
Urban Heat

Lisbon is a European Mediterranean city, greatly exposed to heatwaves (HW), according to recent trends and climate change prospects. Considering the Atlantic influence, air temperature observations from Lisbon’s mesoscale network are used to investigate the interactions between background weather and the urban thermal signal (UTS) in summer. Days are classified according to the prevailing regional wind direction, and hourly UTS is compared between HW and non-HW conditions. Northern-wind days predominate, revealing greater maximum air temperatures (up to 40 °C) and greater thermal amplitudes (approximately 10 °C), and account for 37 out of 49 HW days; southern-wind days have milder temperatures, and no HWs occur. Results show that the wind direction groups are significantly different. While southern-wind days have minor UTS variations, northern-wind days have a consistent UTS daily cycle: a diurnal urban cooling island (UCI) (often lower than –1.0 °C), a late afternoon peak urban heat island (UHI) (occasionally surpassing 4.0 °C), and a stable nocturnal UHI (1.5 °C median intensity). UHI/UCI intensities are not significantly different between HW and non-HW conditions, although the synoptic influence is noted. Results indicate that, in Lisbon, the UHI intensity does not increase during HW events, although it is significantly affected by wind. As such, local climate change adaptation strategies must be based on scenarios that account for the synergies between potential changes in regional air temperature and wind.

Effects of Air Temperature on Combustion Characteristics of LPG Diffusion Flame

2020 ◽  
Vol 1008 ◽  
pp. 128-138
Author(s):  
Ahmed M. Salman ◽  
Ibrahim A. Ibrahim ◽  
Hamada M. Gad ◽  
Tharwat M. Farag
Keyword(s):  
Air Temperature ◽  
Diffusion Flame ◽  
Nitrogen Addition ◽  
Flame Length ◽  
Combustion Characteristics ◽  
Operating Conditions ◽  
Low Oxygen ◽  
Air Temperatures ◽  
Air Stream ◽  
Wide Range

In the present study, the combustion characteristics of LPG gaseous fuel diffusion flame at elevated air temperatures were experimentally investigated. An experimental test rig was manufactured to examine a wide range of operating conditions. The investigated parameters are the air temperatures of 300, 350, 400, 450, and 500 K with constant percentage of nitrogen addition in combustion air stream of 5 % to give low oxygen concentration of 18.3 % by mass at constant air swirl number, air to fuel mass ratio, and thermal load of 1.5, 30, and 23 kW, respectively. The gaseous combustion characteristics were represented as axial and radial temperatures distributions, temperatures gradient, visible flame length and species concentrations. The results indicated that as the air temperature increased, the chemical reaction rate increased and flame volume decreased, the combustion time reduced leading to a reduction in flame length. The NO concentration reaches its maximum values near the location of the maximum centerline axial temperature. Increasing the combustion air temperature by 200 K, the NO consequently O2 concentrations are increased by about % 355 and 20 % respectively, while CO2 and CO concentrations are decreased by about % 21 and 99 % respectively, at the combustor end.

scholarly journals Quantifying the Independent Influences of Land Cover and Humidity on Microscale Urban Air Temperature Variation in Hot Summer: Methods of Path Analysis and Genetic SVR

Atmosphere ◽  
2020 ◽  
Vol 11 (12) ◽  
pp. 1377
Author(s):  
Weifang Shi ◽  
Nan Wang ◽  
Aixuan Xin ◽  
Linglan Liu ◽  
Jiaqi Hou ◽  
...  
Keyword(s):  
Relative Humidity ◽  
Land Cover ◽  
Path Analysis ◽  
Temperature Variation ◽  
Direct Effect ◽  
Air Temperature ◽  
Urban Areas ◽  
Support Vector ◽  
Urban Air ◽  
Air Temperatures

Mitigating high air temperatures and heat waves is vital for decreasing air pollution and protecting public health. To improve understanding of microscale urban air temperature variation, this paper performed measurements of air temperature and relative humidity in a field of Wuhan City in the afternoon of hot summer days, and used path analysis and genetic support vector regression (SVR) to quantify the independent influences of land cover and humidity on air temperature variation. The path analysis shows that most effect of the land cover is mediated through relative humidity difference, more than four times as much as the direct effect, and that the direct effect of relative humidity difference is nearly six times that of land cover, even larger than the total effect of the land cover. The SVR simulation illustrates that land cover and relative humidity independently contribute 16.3% and 83.7%, on average, to the rise of the air temperature over the land without vegetation in the study site. An alternative strategy of increasing the humidity artificially is proposed to reduce high air temperatures in urban areas. The study would provide scientific support for the regulation of the microclimate and the mitigation of the high air temperature in urban areas.

scholarly journals Variations of indicative dates of ice regime on Lake Onego based on ground air temperature

2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Vyacheslav N. Baklagin
Keyword(s):  
Air Temperature ◽  
Regression Equations ◽  
Early Formation ◽  
Air Temperatures ◽  
Ice Regime ◽  
Break Up ◽  
Ice Period ◽  
Ice Phenomena

The paper shows the changes in the dates (complete freeze-up, ±5 days/°C and complete ice clearance, ±3 days/°C) of the ice regime in Lake Onego depending on changes in average air temperature within the preceding two-month periods (autumn and spring). The regression equations for their calculation based on previous three- and four-month periods according to the 2000-2018 data are also provided. Indicative dates of ice regime based on accumulated air temperatures within the ice period of Lake Onego were also established (early formation of ice phenomena, complete freeze-up phase, beginning of the break-up phase and complete ice clearance). Together with the data on expected air temperature above the lake’s surface, these dependencies enable us to predict the indicative dates of the ice regime.

Sign in / Sign up

Export Citation Format

Share Document