Soil temperature regime in a forested Appalachian watershed

1986 ◽  
Vol 16 (3) ◽  
pp. 624-629 ◽  
Author(s):  
S. J. Tajchman ◽  
C. M. Minton
Keyword(s):  
Surface Temperature ◽  
Soil Temperature ◽  
Soil Layer ◽  
The North ◽  
Soil Temperature Regime ◽  
Temperature Ranges ◽  
The Mean ◽  
The Difference ◽  
Topographic Positions ◽  
Lower Slope

Daily and seasonal variations in soil temperature at various topographic positions in a forested catchment are compared. The experimental sites were designed as ridgetop, north-facing lower slope, south-facing lower slope, and southwest-facing slope. On sunny days during the growing season, the surface temperature had the greatest amplitude (7.8 °C) at the south-facing upper slope and the smallest amplitude (4.0 °C) at the north-facing slope; the remaining sites were intermediate. The maximum surface temperature was observed in the afternoon at all sites. With increasing depth, daily soil temperature ranges diminished and, below 10 cm depth, they were less than 1 °C. Under overcast conditions, daily soil temperature fluctations lessened. For individual months, the mean temperatures of the 2–30 cm soil layer generally varied among all sites by less than 1 °C and never the difference exceeded 1.8 °C. The surface temperature variations and their differences among sites appear to be the most distinguished feature of the soil thermal regime and they seem to be aspect related.

scholarly journals Soil temperature regimes in Finland

1998 ◽  
Vol 7 (4) ◽  
pp. 507-512 ◽  
Author(s):  
M. YLI-HALLA ◽  
D. MOKMA
Keyword(s):  
Soil Temperature ◽  
Temperature Regime ◽  
Soil Surface ◽  
Soil Classification ◽  
Soil Taxonomy ◽  
The North ◽  
Temperature Regimes ◽  
Soil Temperature Regime ◽  
The Mean ◽  
The Difference

Soil temperature regime substantially influences soil classification in Soil Taxonomy particularly in temperate areas. To facilitate correct classification of soils of Finland, the temperature regimes in soils of the country were determined. The mean annual soil temperature, measured at 50 cm below soil surface, ranged from 6.4°C at the warmest site (Anjala) to 1.9°C at the coldest one (Utsjoki, Kevo), and the mean summer soil temperature from 13.7°C to 6.2°C at the same stations, all being in the range of the cryic temperature regime. The mean annual soil temperature was 2 to 5°C higher than the mean annual air temperature, the difference (Y, °C) depending on the duration of snow coverage (X, days) according to the following equation: Y = 0.0305 X - 2.16, R2 = 0.91, n = 9. Even soils of the warmest areas in southern Finland and the mineral soils of the coldest areas in the north, at least for the most part, have cryic soil temperature regimes. Therefore, most soils of Finland, classified according to Soil Taxonomy, have names where the cryic temperature regime appears on the suborder or great group level.;

Ocular surface temperature differences in glaucoma

2021 ◽  
pp. 112067212110237
Author(s):  
Ari Leshno ◽  
Ori Stern ◽  
Yaniv Barkana ◽  
Noa Kapelushnik ◽  
Reut Singer ◽  
...  
Keyword(s):  
Surface Temperature ◽  
Thermal Imaging ◽  
Ocular Surface ◽  
Open Angle Glaucoma ◽  
Tissue Temperature ◽  
Body Temperatures ◽  
Current Thinking ◽  
Imaging Camera ◽  
The Mean ◽  
The Difference

Purpose: Accumulating evidence suggests that neuroinflammation and immune response are part of the sequence of pathological events leading to optic nerve damage in glaucoma. Changes in tissue temperature due to inflammation can be measured by thermographic imaging. We investigated the ocular surface temperature (OST) profile of glaucomatous eyes to better understand the pathophysiology of these conditions. Methods: Subjects diagnosed with glaucoma (primary open angle glaucoma [POAG] or pseudo exfoliation glaucoma [PXFG]) treated at the Sam Rothberg Glaucoma Center (11/2019–11/2020.) were recruited. Healthy subjects with no ocular disease served as controls. The Therm-App thermal imaging camera was used for OST acquisition. Room and body temperatures were recorded, and the mean temperatures of the medial cantus, lateral cantus, and cornea were calculated with image processing software. Results: Thermographic images were obtained from 52 subjects (52 eyes: 25 POAG and 27 PXFG) and 66 controls (66 eyes). Eyes with glaucoma had a significantly higher OST compared to controls (mean 0.9 ± 0.3°C, p < 0.005). The difference between the two groups remained significant after adjustment for age, sex, intraocular pressure (IOP) and room and body temperatures. Lens status and topical IOP-lowering medication did not significantly affect OST. A subgroup analysis revealed that the OST was higher among eyes with POAG compared to eyes with PXFG, but not significantly. Conclusions: Differences in the OST between glaucomatous and normal eyes strengthens current thinking that inflammation affects the pathophysiology of glaucoma. Longitudinal studies are warranted to establish the prognostic value of thermographic evaluations in these patients.

scholarly journals Soil temperature study in Puerto Rico

1969 ◽  
Vol 93 (3-4) ◽  
pp. 149-171
Author(s):  
Jorge L. Lugo-Camacho ◽  
Miguel A. Muñoz ◽  
Juan Pérez-Bolívar ◽  
Gregory R. Brannon
Keyword(s):  
Puerto Rico ◽  
Soil Moisture ◽  
Soil Temperature ◽  
Sea Level ◽  
Air Temperature ◽  
Temperature Regime ◽  
Soil Series ◽  
Soil Temperature Regime ◽  
The Mean ◽  
Mean Annual Air Temperature

Soil temperature measurements from a climate monitoring network in Puerto Rico were evaluated and the difference between mean summer and mean winter soil temperature, known as isotivity value, was calculated. Air and soil temperature was collected from five weather stations of the USDA-Natural Resources Conservation Service from sea level to 1,019 m above sea level and from different soil moisture regimes. Isotivity values ranged from 1.2 to 3.9° C with an average of 2.6° C. The 750-m elevation was identified as the limit between the isohyperthermic and isothermic soil temperature regimes in the perudic soil moisture regime in Puerto Rico. The greatest differences between mean annual soil temperature and mean annual air temperature were observed at Guánica, Combate and Guilarte (2.1 ° C) stations. The smallest differences were observed at Maricao (0.8° C) and Isabela (1.8° C) stations. The study also indicated that the mean annual soil temperature in Puerto Rico can be estimated by adding 1.8° C to the mean annual air temperature or by the equation y = -0.007x + 28.0° C. The equation indicates that 97 percent of the time the behavior of the mean annual soil temperature is a function of elevation. According to the updated soil temperature regime boundaries, eight soil series were established in the Soil Survey of San Germán Area. In an area under the isothermic soil temperature regime, four soil series were classified as Oxisols (Haploperox), two soil series as Inceptisols (Eutrudepts) and two soil series as Mollisols (Argiudolls). This is the first field recognition of the Haploperox soil great group in the United States and its territories.

scholarly journals Relationship between newborn leptin levels and selected growth parameters

2019 ◽  
Vol 47 (6) ◽  
pp. 2591-2597 ◽  
Author(s):  
Amer Mahmoud Sindiani ◽  
Rawan Obeidat ◽  
Omar Jbarah ◽  
Ethar Hazaimeh
Keyword(s):  
Gestational Age ◽  
Head Circumference ◽  
Growth Parameters ◽  
Cross Sectional ◽  
Intrauterine Growth ◽  
The North ◽  
Term Newborns ◽  
The Mean ◽  
The Difference ◽  
Umbilical Cord Vein

Objectives This study aimed to determine leptin levels in term newborns who were born in the north of Jordan. We also aimed to investigate the relationships of leptin levels with fetal growth parameters, and to assess the difference in leptin levels according to sex and gestational age. Methods A cross-sectional descriptive study that involved 170 term newborns was conducted. A working sheet for data collection was created for each newborn and included sex, weight, length, head circumference, gestational age, and Apgar score. Blood samples were obtained from the umbilical cord vein of newborns after delivery to measure serum leptin levels. Data are shown as frequency, percentages, means, and standard deviations. Results We found that the mean leptin level was 1.17 ± 0.48 ng/mL. The independent t-test showed that the mean leptin level in boys (0.93 ± 0. 34 ng/mL) was significantly lower than that in girls (1.38 ± 0.47 ng/mL). Pearson’s correlations showed that leptin levels of newborns were positively and significantly correlated with weight, length, and head circumference. Conclusion In Jordanian healthy term newborns, leptin levels correlate with sex and intrauterine growth parameters.

scholarly journals XXVII. On Holtenia, a genus of vitreous sponges

1869 ◽  
Vol 159 ◽  
pp. 701-720 ◽  
Keyword(s):  
Surface Temperature ◽  
North Atlantic ◽  
Small Proportion ◽  
Gulf Stream ◽  
Deep Sea ◽  
Minimum Temperature ◽  
The North ◽  
The Mean ◽  
The North Atlantic ◽  
Amorphous Particles

During the deep-sea dredging cruise of Her Majesty’s Ship 'Lightning' in the autumn of the year 1868, the 6th of September was occupied in dredging at the depth of 530 fathoms in latitude 59° 36' N., and longitude 7° 20' W., only about 20 miles beyond the 100-fathom line of the Coast Survey of Scotland, slightly to the westward of north of the Butt of the Lews. The minimum temperature indicated by the mean of three thermometers (which registered 47°, 47°∙5, and 47°∙5 Fahr. respectively) was 47°∙3 Fahr, the surface-temperature being 52°5 Fahr. During the day there were four successful hauls of the dredge, which came up each time full of a pale-grey tenacious mud, consisting in a great measure of minute amorphous particles of carbonate of lime mixed with “coccoliths” and “coccospheres.” There was only a small proportion of the Globigerinæ and other minute Rhizopods which are so abundant and characteristic over the whole of the warm or “Gulf-stream” area of the North Atlantic. The mud was glairy, as if it had been mixed with white of egg; and it contained disseminated through it an immense quantity of extremely delicate siliceous organisms, spicules of sponges, and the shells of Radiolarians and Diatoms. Large Rhizopods of the genera Astrorhiza, Rhabdammina, Cristellaria, Cornuspira , and others were abundant; and there was a somewhat scanty sprinkling of small forms belonging to the higher groups, Echinoderms, Annulosa, and Mollusca. Besides a number of dead shells, chiefly of the Boreal or Scandinavian type, and several undescribed Echinoderms and Crustaceans, the following species were procured living.

scholarly journals XI. Researches on the tides.—tenth series. on the laws of low water at the port of plymouth, and on the permanency of mean water

1839 ◽  
Vol 129 ◽  
pp. 151-161 ◽  
Keyword(s):  
High Water ◽  
Level Line ◽  
English Channel ◽  
Know How ◽  
North Shore ◽  
The North ◽  
South Shore ◽  
The Subject ◽  
The Mean ◽  
The Difference

In former communications to the Society, the laws of high water at Plymouth and other places have been the subject of my researches. These being obtained, the laws of low water are a subject of importance and interest on many accounts. The first ground of my pursuing this subject was the desire to ascertain how far the mean water , that is, the height midway between high and low water, is permanent during the changes which high and low water undergo. That it is approximately so at Ply­mouth, had been ascertained both by Mr. Walker and myself, by means of a com­parison of a short series of observations. But it was desirable to know with more exactness what was the real amount of this permanency, when, by using a long series of observations of high and low water, the irregularities arising from accident, and from taking imperfect cycles of inequalities, were eliminated. There was another reason which made this inquiry important at the present time. An operation has been recently carried on by the direction and at the expense of the British Association, with a view of ascertaining what surface ought to be taken as the permanent level of the sea. A Level Line has been carried with great care and accuracy from the north shore of Somerset to the south shore of Devon ; and the po­sition of this line has been fixed, so as to be recognised at any future time, by means of marks at Axmouth, at East Quantockshead, at Stolford, and at Portishead. This line has also been referred to the sea at its extremities ; and the observations show that the height of mean water coincides, at least very nearly, at different places, as well as at the same place at different times. While the difference of levels of low water at Axmouth on the English Channel, and Wick Rocks on the Bristol Channel, is not less than twelve feet; the mean water at those two places coincides in level within a few inches. In order to determine further what accuracy may be attained in this result, we are led to inquire what is the degree of permanency at one place. I may further add, that it cannot but be instructive to know how far the corrections of the height and time of low water, for lunar parallax and declination, agree in form and amount with the same corrections already obtained for high water.

SUMMER TEMPERATURES OF CRYOSOLIC SOILS IN THE NORTH-CENTRAL KEEWATIN, N.W.T.

1980 ◽  
Vol 60 (2) ◽  
pp. 311-327 ◽  
Author(s):  
CHARLES TARNOCAI
Keyword(s):  
Soil Temperature ◽  
Slope Position ◽  
North Central ◽  
Soil Material ◽  
The North ◽  
Soil Temperatures ◽  
Summer Temperatures ◽  
The Mean

Soil temperatures were measured at six depths within 1 m of the surface on 10 Cryosolic soils in the north-central Keewatin area during the summer of 1976. The mean soil temperatures during the study period varied between 1.7 °C and 8.2 °C at a depth of 20 cm and −0.2 °C and 6.0 °C at a depth of 50 cm. The maximum and minimum soil temperatures at a depth of 20 cm ranged from 4.4 °C to 13.9 °C and from −0.6°C to 3.9 °C, respectively, while those at a depth of 50 cm ranged from −0.2 °C to 6.7 °C and from −1.1 °C to 2.2 °C, respectively. During the study period a freeze-back of 30 cm or more occurred from the permafrost on several sites. Soil temperatures were markedly higher where the soil material and vegetation were disturbed. The effects of drainage, soil materials, aspect, slope position, vegetation and peat cover on the soil temperature are discussed.

scholarly journals The Shift of the Northern Node of the NAO and Cyclonic Rossby Wave Breaking

2012 ◽  
Vol 25 (22) ◽  
pp. 7973-7982 ◽  
Author(s):  
Yi-Hui Wang ◽  
Gudrun Magnusdottir
Keyword(s):  
Rossby Wave ◽  
Wave Breaking ◽  
Geographical Location ◽  
Mean Flow ◽  
Decadal Time Scale ◽  
Rossby Wave Breaking ◽  
The North ◽  
The Mean ◽  
The Difference ◽  
The North Atlantic Oscillation

Abstract Several studies have found an eastward shift in the northern node of the North Atlantic Oscillation (NAO) during the winters of 1978–97 compared to 1958–77. This study focuses on the connection between this shift of the northern node of the NAO and Rossby wave breaking (RWB) for the period 1958–97. It is found that the region of frequent cyclonic RWB underwent a northeastward shift at high latitudes in the latter 20-yr period. On a year-to-year basis, the cyclonic RWB region moves along a southwest–northeast (SW–NE)-directed axis. Both latitude and longitude of the winter maximum frequency of cyclonic RWB occurrence are positively correlated with the NAO index. To investigate the role of location of cyclonic RWB in influencing the NAO pattern, the geographical location of frequent cyclonic RWB is divided into two subdomains located along the SW–NE axis, to the south (SW domain) and east (NE domain) of Greenland. Two composites are assembled as one cyclonic RWB occurrence is detected in one of the two subdomains in 6-hourly instantaneous data. The forcing of the mean flow due to cyclonic RWB within individual subdomains is found to be locally restricted to where the breaking occurs, which is usually near the jet exit region and far removed from the jet core. The difference in the jet between the NE and SW composites resembles the difference in the mean jet between the 1978–97 and 1958–77 periods, which suggests that the change in cyclonic RWB occurrence in the two subdomains is associated with the wobbling of the jet on the decadal time scale.

The lubrication of rollers II. Film thickness with relation to viscosity and speed

1961 ◽  
Vol 254 (1040) ◽  
pp. 223-236 ◽  
Keyword(s):  
Film Thickness ◽  
Surface Temperature ◽  
Frictional Heating ◽  
Specific Effect ◽  
Elastohydrodynamic Lubrication ◽  
Rolling Speed ◽  
Frictional Heat ◽  
Oil Viscosity ◽  
The Mean ◽  
The Difference

Systematic measurements with a disk machine of the thickness of the hydrodynamic oil film between loaded rollers have been made with respect to load, rolling speed, sliding speed and oil viscosity. It has been found that the viscosity of greatest im portance with respect to film thickness is the viscosity of the oil at the surface temperature of the disks (tjs) ; the viscosity of the oil supplied by the lubricating jet and the viscosity attained by the oil on its passage through the pressure zone are unim portant. It has been shown that film thickness is independent of load at loads exceeding 7 x 10 7 dyn cm -1 , but is dependent upon the rolling speed u (the mean peripheral speed of the disks) as well as upon rjs. To within +15 % all the results are expressed by h* = 0-8[(m^ ) /100] 0.5 where h% is the film thickness in microns when utjs is expressed in dyncm -1 . Particularly is it noteworthy that this same expression remained true even when sliding was introduced. (The ranges of conditions covered by the experiments were loads from 7 x 10 7 to 2 x 10 8 dyncm -1 , rolling speeds from 32 to 1000 cm s -1 , sliding speeds up to 480 cm s -1 and values of rjs from 0.14 to 1.19P.) It is also shown that an implication of the insensitivity to sliding is that on the entry side there is little frictional heating of the oil due to the sliding up to a point where the pressure approaches 1 x 10 9 dyncm -2 . The experimental results, have been compared with the theory of the elastohydrodynamic lubrication at the conjunction of the disks. The theory disregards frictional heating and predicts a film thickness proportional to (zb/s) 0.7 in contrast with the exponent of 0.5 given by experiment. Evidence is cited that the difference is not due to frictional heat but it is suggested that the discrepancy is due to a specific effect of speed upon the increase in viscosity which oils exhibit under pressure.

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