Soil temperatures and stability of ice-cemented ground in the McMurdo Dry Valleys, Antarctica

1998 ◽  
Vol 10 (1) ◽  
pp. 31-38 ◽  
Author(s):  
Christopher P. McKay ◽  
Michael T. Mellon ◽  
E. Imre Friedmann
Keyword(s):  
Water Vapour ◽  
Temperature Measurements ◽  
Dry Valleys ◽  
Frost Point ◽  
Air Temperatures ◽  
Soil Temperatures ◽  
Net Flux ◽  
The Mean ◽  
Long Timescales ◽  
Over Time

Year-round temperature measurements at 1600 m elevation during 1994 in the Asgard Range Antarctica, indicate that the mean annual frost point of the ice-cemented ground, 25 cm below the surface, is −21.7 ± 0.2°C and the mean annual frost point of the atmosphere is −27.5 ± 1.0°C. The corresponding mean annual temperatures are −24.9°C and −23.3°C. These results imply that there is a net flux of water vapour from the ice to the atmosphere resulting in a recession of the ice-cemented ground by about 0.4–0.6 mm yr1. The level of the ice-cemented permafrost is about 12 cm below the level of dry permafrost. The summer air temperatures would have to increase about 7°C for thawing temperatures to just reach the top of the subsurface ice. Either subsurface ice at this location is evaporating over time or there are sporadic processes that recharge the ice and maintain equilibrium over long timescales.

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.

Effect of environmental temperature on body temperature and metabolic heat production in a heterothermic rodent,Spermophilus tereticaudus

2002 ◽  
Vol 205 (14) ◽  
pp. 2099-2105 ◽  
Author(s):  
K. Mark Wooden ◽  
Glenn E. Walsberg
Keyword(s):  
Body Temperature ◽  
Ground Squirrel ◽  
Environmental Temperature ◽  
Body Temperatures ◽  
Metabolic Heat ◽  
Thermoneutral Zone ◽  
Air Temperatures ◽  
The Mean ◽  
Maximum Body ◽  
Over Time

SUMMARYThis study quantifies the thermoregulatory ability and energetics of a mammal, the round-tailed ground squirrel Spermophilus tereticaudus,that can relax thermoregulatory limits without becoming inactive. We measured body temperature and metabolic rate in animals exposed for short periods (1 h)to air temperatures ranging from 10 to 45 °C and for long periods (8 h) to air temperatures ranging from 10 to 30 °C. Within 45 min of exposure to air temperatures ranging from 10 to 45 °C, the mean body temperatures of alert and responsive animals ranged from 32.1 °C(Tair=10 °C) to 40.4 °C(Tair=45 °C). This thermolability provided significant energetic savings below the thermoneutral zone, ranging from 0.63 W (18 %) at 10 °C to 0.43 W (43 %) at 30 °C. When exposed for 8 h to air temperatures between 10 and 30 °C, animals varied their body temperature significantly over time. At all air temperatures, the lowest body temperature(maintained for at least 1 h) was 31.2 °C. The highest body temperatures(maintained for at least 1 h) were 33.6 °C at 10 °C, 35.3 °C at 20°C and 36.3 °C at 30 °C. The energetic savings realized by maintaining the minimum rather than the maximum body temperature was 0.80 W(25 %) at 10 °C, 0.71 W (33 %) at 20 °C and 0.40 W (47 %) at 30°C. This study demonstrates in several ways the ability of this species to adjust energy expenditure through heterothermy.

scholarly journals Dry permafrost over ice-cemented ground at Elephant Head, Ellsworth Land, Antarctica

2019 ◽  
Vol 31 (05) ◽  
pp. 263-270 ◽  
Author(s):  
Christopher P. McKay ◽  
Edward Balaban ◽  
Simon Abrahams ◽  
Nick Lewis
Keyword(s):  
Water Activity ◽  
Dry Valleys ◽  
Frost Point ◽  
Temperature And Humidity ◽  
Humidity Measurements ◽  
Permafrost Ground ◽  
The Mean ◽  
Dry Soil ◽  
Special Region

AbstractDry permafrost - ground with temperature always below 0°C and containing negligible ice - overlying ice-cemented ground has been reported in the Dry Valleys of Antarctica and on Mars. Here we report on a new site (79°49.213'S, 83°18.860'W, 718 m elevation) located on the side of Mount Dolence in Ellsworth Land, Antarctica. Year-round temperature and humidity measurements indicate that dry permafrost is present between depths of 13.5 and 49.0 cm - the location of ice-cemented ground. The mean annual frost point of the ice-cemented ground is -17.0 ± 0.2°C and the mean annual frost point of the atmosphere is -22.7 ± 1°C. The corresponding mean annual temperatures are -19.2°C and -20.3°C. Neither the temperature of the ice-cemented ground nor the air rise above freezing. Both the dry permafrost and the ice table may be habitable. In the dry soil at 3 cm depth there are 80 hours in the summer when temperature exceeds -5°C and water activity exceeds 0.8. At the ice table, temperature exceeds -10°C and water activity exceeds 0.8 for 35 hours in the year. The ice table and the dry permafrost above it would be considered a ‘Special Region’ on Mars. Further microbial investigation of this site is indicated.

scholarly journals An Assessment of Environmental Conditions Preceding Outbreaks of Sclerotinia Blight of Peanut in Virginia1

1995 ◽  
Vol 22 (2) ◽  
pp. 90-93 ◽  
Author(s):  
P. M. Phipps
Keyword(s):  
Disease Onset ◽  
Disease Outbreaks ◽  
Soil Surface ◽  
Direct Sunlight ◽  
Vine Growth ◽  
Air Temperatures ◽  
Sclerotinia Blight ◽  
Initial Onset ◽  
Soil Temperatures ◽  
The Mean

Abstract Records of outbreaks of Sclerotinia blight of peanut at the Tidewater Center in Suffolk were summarized over a 16-yr period (1978–93). Initial outbreaks of the disease were determined through intensive scouting of fields at weekly intervals. First occurrences of Sclerotinia blight occurred between 10 July and 7 Sept., or 62 to 120 d after planting (DAP). The mean and median dates of initial outbreaks were 28 July (79 DAP) and 25 July (76 DAP), respectively. The initial onset of disease always occurred after vines were within 15 cm of touching between rows or after vines had lapped between rows. Under these conditions, a canopy of dense foliage shaded the soil surface and infection sites inside rows from direct sunlight. Rainfall summaries showed the heaviest accumulations were from 6 to 15 d before disease outbreaks. Maximum and minimum air temperatures over the 15-d period prior to disease onset averaged ca. 32 C and 20 C, respectively. Maximum and minimum soil temperatures at the 10-cm depth averaged ca. 30 and 25 C, respectively, during this same period. The results of this study provide evidence that vine growth and rainfall are primary determinants in triggering the onset of Sclerotinia blight of peanut in southeastern Virginia.

Impacts of using polyethylene sleeves and wavelength selective mulch in vineyards. I. Effects on air and soil temperatures and degree day accumulation

2004 ◽  
Vol 84 (2) ◽  
pp. 545-553 ◽  
Author(s):  
P. A. Bowen ◽  
C. P. Bogdanoff ◽  
B. Estergaard
Keyword(s):  
Single Layer ◽  
Degree Day ◽  
Weed Growth ◽  
Air Temperatures ◽  
Soil Temperatures ◽  
The Mean ◽  
Maximum Temperatures ◽  
Two Stages ◽  
Polyethylene Mulch ◽  
Diurnal Period

Effects on soil and air temperatures of wavelength-selective polyethylene mulch applied in planted rows, and clear polyethylene enclosures (sleeves) applied around vine canes or cordons for 7 wk in the spring were determined in three Merlot vineyards in the Okanagan Valley, British Columbia. Three sleeve configurations were studied: single-layer and closed at bottom; single-layer with bottom ventilation added after 5 wk; and double-layer with bottom ventilation added after 5 wk. All sleeves were perforated at the top between two supporting trellis catch wires, and were stapled closed at the bottom under the cordon or cane. Sleeve removal was either all at once or in two stages by first opening the top then removing the sides 6 d later. The sleeves increased mean air temperatures by ca. 1 to 2°C and maximum temperatures by ca. 5 to 8°C, and decreased minimum temperatures by ca. 1 to 2 °C, depending on the vineyard, measurement period, and sleeve configuration. Adding bottom ventilation to sleeves increased the mean minimum nighttime temperature by ca. 1°C at one vineyard but had no effect at the other two sites. Degree day (base 10°C) accumulati on inside sleeves was 1.5 to 2 times that of ambient, depending on the site, which increased total degree day accumulations for the season by 4.1 to 7.9%. The polyethylene mulch increased soil temperatures by ca. 2°C continuously over the diurnal period at two of the vineyards, but at the third where there was significant weed growth under the mulch the increase was less and only at night. Key words: Wine grapes, plasticulture

scholarly journals Results of a phenological study at a young Norway spruce (Picea abies/L./Karst)

2010 ◽  
Vol 58 (5) ◽  
pp. 35-42
Author(s):  
Emilie Bednářová ◽  
Lucie Merklová ◽  
Sabina Truparová
Keyword(s):  
Picea Abies ◽  
Norway Spruce ◽  
Meteorological Parameters ◽  
Correlation Coefficients ◽  
Early Spring ◽  
Phenological Stages ◽  
Air Temperatures ◽  
Sum Of Effective Temperatures ◽  
Soil Temperatures ◽  
The Mean

The paper deals with results of phenological studies of Norway spruce (Picea abies/L./ Karst.) in a mixed stand. This broad range was important in spring phenological stages. High correlations were determined between the mean air temperature, soil temperature and the start of phenological stages. Relationships between the onset of phenological stages and changes in meteorological parameters were expressed by the sum of effective air temperatures exceeding 0 and 5 °C. To evaluate the relationships by means of the sum of effective temperatures >5 °C, the stage of budbreak was most important.The onset of budbreak in Norway spruce occurred on average in the 125th day in the period 2005 to 2008. First, the stage of budbreak in spruce began the 121st day and at the latest the 128th day in 2005. The most often budbreak was in 2007. The onset of foliage in spruce began between the 128th day and the 136th day. Full 100% foliage occurred in 2007, viz. the 159th day, i.e. 12 day earlier than in the previous year. In 2005, full foliage occurred the 171st day. The air and soil temperatures affected spring phenological stages during the early spring, which was demonstrated by high correlation coefficients.

Optimum prediction of atmospheric temperature using GPS radio occultation measurements

2017 ◽  
Vol 919 (1) ◽  
pp. 48-51
Author(s):  
N.H. Javadov ◽  
R.A. Eminov ◽  
N.Ya. Ismailov
Keyword(s):  
Radio Occultation ◽  
General Procedure ◽  
Atmospheric Temperature ◽  
Mean Value ◽  
Optimization Criterion ◽  
Temperature Measurements ◽  
Gps Radio Occultation ◽  
Applied Optimization ◽  
Quadratic Deviation ◽  
The Mean

The matters of optimum forecasting atmospheric temperature using GPS radio occultation measurements are considered. The analysis of the available data regarding to the comparison of temperature measurements using radio occultation method and radiosondes was made. As a result it was concluded that the mean value of those results’ difference and also the mean quadratic deviation of these difference increases in common by increase of the forecasting time. In order to prevent surplus loading of telemetry channels and broadcasting inaccurate forecast values via them the optimization of general procedure of radio occultation temperature measurements are carried out using fine functions method. For optimization the concurrent parameters, changing on antiphase order are determined. It is found out that utilization of fine function method taking into account the applied optimization criterion and some limitation conditions make it possible to optimize the whole procedure of forecasting atmospheric temperature using the GPS radio occultation measurements.

scholarly journals Kinetic analysis and optimisation of 18F-rhPSMA-7.3 PET imaging of prostate cancer

2021 ◽  
Author(s):  
Simona Malaspina ◽  
Vesa Oikonen ◽  
Anna Kuisma ◽  
Otto Ettala ◽  
Kalle Mattila ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Metastatic Disease ◽  
Uptake Kinetics ◽  
Whole Body ◽  
Target Area ◽  
Post Injection ◽  
The Mean ◽  
Pet Radiopharmaceutical ◽  
Time Frames ◽  
Over Time

Abstract Purpose This phase 1 open-label study evaluated the uptake kinetics of a novel theranostic PET radiopharmaceutical, 18F-rhPSMA-7.3, to optimise its use for imaging of prostate cancer. Methods Nine men, three with high-risk localised prostate cancer, three with treatment-naïve hormone-sensitive metastatic disease and three with castration-resistant metastatic disease, underwent dynamic 45-min PET scanning of a target area immediately post-injection of 300 MBq 18F-rhPSMA-7.3, followed by two whole-body PET/CT scans acquired from 60 and 90 min post-injection. Volumes of interest (VoIs) corresponding to prostate cancer lesions and reference tissues were recorded. Standardised uptake values (SUV) and lesion-to-reference ratios were calculated for 3 time frames: 35–45, 60–88 and 90–118 min. Net influx rates (Ki) were calculated using Patlak plots. Results Altogether, 44 lesions from the target area were identified. Optimal visual lesion detection started 60 min post-injection. The 18F-rhPSMA-7.3 signal from prostate cancer lesions increased over time, while reference tissue signals remained stable or decreased. The mean (SD) SUV (g/mL) at the 3 time frames were 8.4 (5.6), 10.1 (7) and 10.6 (7.5), respectively, for prostate lesions, 11.2 (4.3), 13 (4.8) and 14 (5.2) for lymph node metastases, and 4.6 (2.6), 5.7 (3.1) and 6.4 (3.5) for bone metastases. The mean (SD) lesion-to-reference ratio increases from the earliest to the 2 later time frames were 40% (10) and 59% (9), respectively, for the prostate, 65% (27) and 125% (47) for metastatic lymph nodes and 25% (19) and 32% (30) for bone lesions. Patlak plots from lesion VoIs signified almost irreversible uptake kinetics. Ki, SUV and lesion-to-reference ratio estimates showed good agreement. Conclusion 18F-rhPSMA-7.3 uptake in prostate cancer lesions was high. Lesion-to-background ratios increased over time, with optimal visual detection starting from 60 min post-injection. Thus, 18F-rhPSMA-7.3 emerges as a very promising PET radiopharmaceutical for diagnostic imaging of prostate cancer. Trial Registration NCT03995888 (24 June 2019).

scholarly journals A New Multiplatform Model for Outpatient Prenatal and Postpartum Care in a Cohort of COVID-19-Affected Obstetric Patients

2021 ◽  
Vol 18 (10) ◽  
pp. 5144
Author(s):  
Mar Muñoz-Chápuli Gutiérrez ◽  
Ana Durán-Vila ◽  
Javier Ruiz-Labarta ◽  
Pilar Payá-Martínez ◽  
Pilar Pintado Recarte ◽  
...  
Keyword(s):  
Clinical Manifestations ◽  
Specific Treatment ◽  
Rt Pcr ◽  
Good Adherence ◽  
Major Morbidity ◽  
Reference Hospital ◽  
The Mean ◽  
Discharge From Hospital ◽  
Over Time

Spain was one of the epicenters of the first wave of the COVID-19 pandemic. We describe in this article the design and results of a new telephone-and-telematic multiplatform model of systematic prenatal and postpartum follow-up for COVID-19-affected women implemented in a tertiary reference hospital in Madrid. We included patients with RT-PCR-confirmed COVID-19 during pregnancy or delivery from 10 March 2020 to 15 December 2020. We had a total of 211 obstetric patients: 148 (70.1%) were tested at the onset of suspicious clinical manifestations and 62 (29.4%) were tested in the context of routine screening. Of all the patients, 60 women (28.4%) were asymptomatic and 97 (46%) presented mild symptoms. Fifty-one women (24.2%) were admitted to our hospital for specific treatment because of moderate or severe symptoms. We had no missed cases and a good adherence. The mean number of calls per patient was 2.3. We performed 55 in-person visits. We analyzed the complexity of our program over time, showing a two-wave-like pattern. One patient was identified as needing hospitalization and we did not record major morbidity. Telemedicine programs are a strong and reproducible tool to reach to pregnant population affected by COVID-19, to assess its symptoms and severity, and to record for pregnancy-related symptoms both in an outpatient regime and after discharge from hospital.

scholarly journals Impact of Shade and Fogging on High Tunnel Production and Mineral Content of Organically Grown Lettuce, Basil, and Arugula in Georgia

Agriculture ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 625
Author(s):  
Savanah Laur ◽  
Andre Luiz Biscaia Ribeiro da Silva ◽  
Juan Carlos Díaz-Pérez ◽  
Timothy Coolong
Keyword(s):  
Mineral Content ◽  
Planting Date ◽  
High Tunnel ◽  
Lactuca Sativa L ◽  
Air Temperatures ◽  
Shade Cloth ◽  
High Tunnels ◽  
Soil Temperatures ◽  
Organically Grown ◽  
The Impact

This study evaluated the impact of shade cloth and fogging systems on the microclimate at the plant canopy level and yield of basil (Oscimum basilicum L.), arugula (Eruca vesicaria subsp. Sativa L.), and lettuce (Lactuca sativa L.) planted in mid-September and early October in high tunnels. Fogging systems were installed at canopy level in plots within shaded (30%) and non-shaded high tunnels. Average air temperatures in the shaded high tunnels were 0.9 °C lower than non-shaded high tunnels during the day. Shade cloth significantly reduced soil temperatures during the day and night periods by 1.5 °C and 1.3 °C, respectively, compared to non-shaded treatments. Fogging systems did not have an impact on air temperature, soil temperature, or relative humidity, but did increase canopy leaf wetness. Shade and fogging did not impact the yield of any of the crops grown. Yield was impacted by planting date, with earlier planting result in higher yields of lettuce and basil. Yields for arugula were greater during the second planting date than the first. Planting date and shade cloth interacted to affect the concentrations of macronutrients.

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