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 Fiber optic distributed temperature sensing for the determination of air temperature

2014 ◽  
Vol 7 (6) ◽  
pp. 6287-6298
Author(s):  
S. A. P. de Jong ◽  
J. D. Slingerland ◽  
N. C. van de Giesen
Keyword(s):  
Solar Radiation ◽  
Correlation Coefficient ◽  
Air Temperature ◽  
Fiber Optic ◽  
Solar Heating ◽  
Temperature Sensing ◽  
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 virtual cable would not be affected by solar heating and would take on the temperature of the surrounding air. The results for a pair of black cables and a pair of white cables were very good. The correlations between standard air temperature measurements and air temperatures derived from both colors had a high correlation coefficient (r2 = 0.99). A thin white cable measured temperatures that were close to air temperature. The temperatures were measured along horizontal cables but the results are especially interesting for vertical atmospheric profiling.

scholarly journals Fiber optic distributed temperature sensing for the determination of the nocturnal atmospheric boundary layer height

2011 ◽  
Vol 4 (2) ◽  
pp. 143-149 ◽  
Author(s):  
C. A. Keller ◽  
H. Huwald ◽  
M. K. Vollmer ◽  
A. Wenger ◽  
M. Hill ◽  
...  
Keyword(s):  
Boundary Layer ◽  
Atmospheric Boundary Layer ◽  
Fiber Optic ◽  
Temperature Inversion ◽  
Nocturnal Boundary Layer ◽  
Temperature Sensing ◽  
Temperature Profiles ◽  
Distributed Temperature Sensing ◽  
Boundary Layer Height

Abstract. A new method for measuring air temperature profiles in the atmospheric boundary layer at high spatial and temporal resolution is presented. The measurements are based on Raman scattering distributed temperature sensing (DTS) with a fiber optic cable attached to a tethered balloon. These data were used to estimate the height of the stable nocturnal boundary layer. The experiment was successfully deployed during a two-day campaign in September 2009, providing evidence that DTS is well suited for this atmospheric application. Observed stable temperature profiles exhibit an exponential shape confirming similarity concepts of the temperature inversion close to the surface. The atmospheric mixing height (MH) was estimated to vary between 5 m and 50 m as a result of the nocturnal boundary layer evolution. This value is in good agreement with the MH derived from concurrent Radon-222 (222Rn) measurements and in previous studies.

scholarly journals Fiber optic distributed temperature sensing for the determination of the nocturnal atmospheric boundary layer height

2010 ◽  
Vol 3 (3) ◽  
pp. 2723-2741 ◽  
Author(s):  
C. A. Keller ◽  
H. Huwald ◽  
M. K. Vollmer ◽  
A. Wenger ◽  
M. Hill ◽  
...  
Keyword(s):  
Boundary Layer ◽  
Atmospheric Boundary Layer ◽  
Fiber Optic ◽  
Temperature Inversion ◽  
Nocturnal Boundary Layer ◽  
Temperature Sensing ◽  
Temperature Profiles ◽  
Distributed Temperature Sensing ◽  
Boundary Layer Height

Abstract. A new method for measuring air temperature profiles in the atmospheric boundary layer at high spatial and temporal resolution is presented. The measurements are based on Raman scattering distributed temperature sensing (DTS) with a fiber optic cable attached to a tethered balloon. These data were used to estimate the height of the stable nocturnal boundary layer. The experiment was successfully deployed during a two-day campaign in September 2009, providing evidence that DTS is well suited for this atmospheric application. Observed stable temperature profiles exhibit an exponential shape confirming similarity concepts of the temperature inversion close to the surface. The atmospheric mixing height (MH) was estimated to vary between 5 m and 50 m as a result of the nocturnal boundary layer evolution. This value is in good agreement to the MH derived from concurrent Radon-222 (222Rn) measurements and in previous studies.

scholarly journals Bed conduction impact on fiber optic distributed temperature sensing water temperature measurements

2015 ◽  
Vol 4 (1) ◽  
pp. 19-22 ◽  
Author(s):  
T. O'Donnell Meininger ◽  
J. S. Selker
Keyword(s):  
Water Temperature ◽  
Diurnal Temperature Range ◽  
Fiber Optic ◽  
Stream Temperature ◽  
Temperature Sensing ◽  
Temperature Measurements ◽  
Distributed Temperature Sensing ◽  
Diurnal Temperature ◽  
Sediment Bed ◽  
Bed Materials

Abstract. Error in distributed temperature sensing (DTS) water temperature measurements may be introduced by contact of the fiber optic cable sensor with bed materials (e.g., seafloor, lakebed, streambed). Heat conduction from the bed materials can affect cable temperature and the resulting DTS measurements. In the Middle Fork John Day River, apparent water temperature measurements were influenced by cable sensor contact with aquatic vegetation and fine sediment bed materials. Affected cable segments measured a diurnal temperature range reduced by 10% and lagged by 20–40 min relative to that of ambient stream temperature. The diurnal temperature range deeper within the vegetation–sediment bed material was reduced 70% and lagged 240 min relative to ambient stream temperature. These site-specific results illustrate the potential magnitude of bed-conduction impacts with buried DTS measurements. Researchers who deploy DTS for water temperature monitoring should understand the importance of the environment into which the cable is placed on the range and phase of temperature measurements.

scholarly journals Thermodynamics of a fast-moving Greenlandic outlet glacier revealed by fiber-optic distributed temperature sensing

2021 ◽  
Vol 7 (20) ◽  
pp. eabe7136
Author(s):  
Robert Law ◽  
Poul Christoffersen ◽  
Bryn Hubbard ◽  
Samuel H. Doyle ◽  
Thomas R. Chudley ◽  
...  
Keyword(s):  
Fiber Optic ◽  
Basal Layer ◽  
Temperature Sensing ◽  
Distributed Temperature Sensing ◽  
Catchment Scale ◽  
Outlet Glacier ◽  
Coarse Spatial Resolution ◽  
High Vertical Resolution ◽  
Fast Motion ◽  
Strain Heating

Measurements of ice temperature provide crucial constraints on ice viscosity and the thermodynamic processes occurring within a glacier. However, such measurements are presently limited by a small number of relatively coarse-spatial-resolution borehole records, especially for ice sheets. Here, we advance our understanding of glacier thermodynamics with an exceptionally high-vertical-resolution (~0.65 m), distributed-fiber-optic temperature-sensing profile from a 1043-m borehole drilled to the base of Sermeq Kujalleq (Store Glacier), Greenland. We report substantial but isolated strain heating within interglacial-phase ice at 208 to 242 m depth together with strongly heterogeneous ice deformation in glacial-phase ice below 889 m. We also observe a high-strain interface between glacial- and interglacial-phase ice and a 73-m-thick temperate basal layer, interpreted as locally formed and important for the glacier’s fast motion. These findings demonstrate notable spatial heterogeneity, both vertically and at the catchment scale, in the conditions facilitating the fast motion of marine-terminating glaciers in Greenland.

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.

Measuring Artificial Recharge with Fiber Optic Distributed Temperature Sensing

Ground Water ◽  
2012 ◽  
Vol 51 (5) ◽  
pp. 670-678 ◽  
Author(s):  
Matthew W. Becker ◽  
Brian Bauer ◽  
Adam Hutchinson
Keyword(s):  
Fiber Optic ◽  
Artificial Recharge ◽  
Temperature Sensing ◽  
Distributed Temperature Sensing

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.

Sign in / Sign up

Export Citation Format

Share Document