scholarly journals A Comparison of SNOTEL and GHCN/CRU Surface Temperatures with Free-Air Temperatures at High Elevations in the Western United States: Data Compatibility and Trends

2005 ◽  
Vol 18 (12) ◽  
pp. 1967-1985 ◽  
Author(s):  
N. C. Pepin ◽  
M. Losleben ◽  
M. Hartman ◽  
K. Chowanski
Keyword(s):  
Air Temperature ◽  
Temperature Difference ◽  
Warming Trend ◽  
High Elevation ◽  
Climatic Research Unit ◽  
Mountain Areas ◽  
Temperature Anomalies ◽  
Surface Temperatures ◽  
Air Temperatures ◽  
Free Air

Abstract This paper compares high-elevation surface temperatures based on the Global Historical Climate Network/Climatic Research Unit (GHCN/CRU) and snow telemetry (SNOTEL) datasets, with simultaneous free-air equivalent temperatures, interpolated from NCEP–NCAR reanalysis. Mean monthly temperature anomalies from 1982 to 1999 are examined for 60 SNOTEL and 296 GHCN/CRU sites at elevations over 500 m with relatively homogenous records. The surface/free-air temperature difference ΔT (Ts − Ta) is calculated for both the SNOTEL and GHCN/CRU datasets. Topography influences the correlation between surface and free-air temperature anomalies. Physically realistic diurnal and seasonal changes in ΔT\E are illustrated. Systematic secular trends in surface temperatures, free-air temperatures, and ΔT are revealed, but the sign and magnitude of change depends on location, meaning that regional signals are weak. The Ts trends are positive for most GHCN and CRU sites, and for SNOTEL sites at night. Daytime cooling in the SNOTEL network reduces the mean daily warming trend. The Ta trends are consistently positive for both networks and are often larger than Ts. Thus mean ΔT trends are negative for both datasets. The smaller sample size in the SNOTEL dataset means that error estimates for regional signals are much wider than for the GHCN/CRU dataset. Trend difference maps identify potentially anomalous SNOTEL records. Trends show no correlation with elevation and topography. Surface trends show higher variability and account for most of the uncertainty in ΔT trends. Sensitivity of trends to time period is also discussed. Such changes in the free-air/surface temperature difference may indicate change in the energy balance of mountain areas.

Comparison of Vertical Soundings and Sidewall Air Temperature Measurements in a Small Alpine Basin

2004 ◽  
Vol 43 (11) ◽  
pp. 1635-1647 ◽  
Author(s):  
C. David Whiteman ◽  
Stefan Eisenbach ◽  
Bernhard Pospichal ◽  
Reinhold Steinacker
Keyword(s):  
Air Temperature ◽  
Land Use Planning ◽  
Lower Cost ◽  
Temperature Inversion ◽  
Eastern Alps ◽  
Static Stability ◽  
Good Correspondence ◽  
Temperature Bias ◽  
Air Temperatures ◽  
Free Air

Abstract Tethered balloon soundings from two sites on the floor of a 1-km-diameter limestone sinkhole in the eastern Alps are compared with pseudovertical temperature “soundings” from three lines of temperature dataloggers on the basin's northwest, southwest, and southeast sidewalls. Under stable nighttime conditions with low background winds, the pseudovertical profiles from all three lines were good proxies for free air temperature soundings over the basin center, with a mean nighttime cold temperature bias of about 0.4°C and a standard deviation of 0.4°C. Cold biases were highest in the upper basin where relatively warm air subsides to replace air that spills out of the basin through the lowest-altitude saddle. On a windy night, standard deviations increased to 1°–2°C. After sunrise, the varying exposures of the dataloggers to sunlight made the pseudovertical profiles less useful as proxies for free air soundings. The good correspondence between sidewall and free air temperatures during high-static-stability conditions suggests that sidewall soundings can be used to monitor temperatures, temperature gradients, and temperature inversion evolution in the sinkhole. Sidewall soundings can produce more frequent profiles at lower cost than can tethersondes or rawinsondes, and extension of these findings to other enclosed or semienclosed topographies may enhance future basic meteorological research or support applications studies in agriculture, forestry, air pollution, and land use planning.

scholarly journals Evaluation of ERA-Interim Air Temperature Data over the Qilian Mountains of China

2020 ◽  
Vol 2020 ◽  
pp. 1-11
Author(s):  
Peng Zhao ◽  
Lu Gao ◽  
Jianhui Wei ◽  
Miaomiao Ma ◽  
Haijun Deng ◽  
...  
Keyword(s):  
Air Temperature ◽  
Warming Trend ◽  
Temperature Data ◽  
Qilian Mountains ◽  
Positive Trend ◽  
Climate Change Research ◽  
Weather Forecasts ◽  
Air Temperatures ◽  
Grid Points ◽  
The Qilian Mountains

In this study, 2 m air temperature data from 24 meteorological stations in the Qilian Mountains (QLM) are examined to evaluate ERA-Interim reanalysis temperature data derived from the European Centre for Medium-Range Weather Forecasts (ECMWF) for the period of 1979–2017. ERA-Interim generally captures the monthly, seasonal, and annual variation very well. High daily correlations ranging from 0.956 to 0.996 indicate that ERA-Interim captures the daily temperature observations very well. However, an average root-mean-square error (RMSE) of ±2.7°C of all stations reveals that ERA-Interim should not be directly applied at individual sites. The biases are mainly attributed to the altitude differences between ERA-Interim grid points and stations. The positive trend (0.457°C/decade) is significant over the Qilian Mountains based on the 1979–2017 observations. ERA-Interim captures the warming trend very well with an increase rate of 0.384°C/decade. The observations and ERA-Interim both show the largest positive trends in summer with the values of 0.552°C/decade and 0.481°C/decade, respectively. We conclude that in general ERA-Interim captures the trend very well for observed 2 m air temperatures and ERA-Interim is generally reliable for climate change research over the Qilian Mountains.

scholarly journals Winter synoptic processes that cause large anomalies of extreme-low air temperatures in Eastern Europe

2018 ◽  
Keyword(s):  
Low Temperature ◽  
Eastern Europe ◽  
Black Sea ◽  
Air Temperature ◽  
Low Temperatures ◽  
Extreme Temperature ◽  
The Black Sea ◽  
Volga River ◽  
Temperature Anomalies ◽  
Air Temperatures

Formulation of the problem. Extreme-low temperatures are an adverse phenomenon for the country’s economy and human living conditions. It is important to have a climatological estimation of typical locations and probability of extreme-low temperatures caused by different synoptic processes, which ideally should be predicted in advance. The purpose of the article. The paper describes the typical synoptic processes that lead to extreme-low temperatures over the past 20 years (1997-2017) in middle latitudes in Eastern Europe. The probability of significant areas with extreme-low temperature and their typical localization during various synoptic processes was investigated. Methods. Definition of “extreme-low temperatures” refers to the temperatures below the 5th percentile of the surface actual temperature distribution in each grid point. To create the sample, anomalies of extreme-low air temperatures over significant areas (more than 20 percent of the sector) were chosen. To divide the synoptic processes into groups, a synoptic analysis was applied. Results. From the sample of 1997-2017, 75 episodes with large areas of extreme-low temperature were identified. The sample contains 13 episodes that cover more than 30% of the Eastern Europe and last from 2 to 11 days, and 12 episodes that have one day duration. Cases with anomalies occupy from 20 to 30% of the territory rarely lasts more than 2-3 days (11 episodes). There are five main groups of processes that lead to significant air temperature anomalies that cover a large area of the chosen domain. These five groups of situations include 75% of all days with large areas of extreme-low air temperature. The first group of processes: there is the movement of the cyclone from the Black Sea towards the Volga river basin region, with the anticyclone located in the northwest of Russia displacing towards the Baltic region or Scandinavia. In this case, temperature anomalies cover almost the entire eastern part of the selected sector. The second group of processes: a vast anticyclone, expanding from Western Siberia in the direction of Belarus (extreme-low temperatures most of time observed in the central part of the sector). The third group of processes: the movement of the “southern” cyclone from the Black Sea to the territory of Ukraine with subsequent displacement to the east (extreme-low temperatures most of time observed in the north-eastern part of the sector). The fourth group of processes: motionless anticyclone over the northeast of the Eastern European sector (high probability of extreme-low temperatures in the south-eastern part of the sector). The fifth group of processes: the northward trajectory of the “southern” cyclone to the territory of Ukraine while strengthening of the anticyclone over the Scandinavia. This one is similar to the first group of processes but differ by more western trajectories of cyclones, and hence different locations of extreme temperature anomalies (north-western part of the sector and eastern part of Ukraine). The remaining 25% of the days with large anomalies are mostly short-lived and observed during 1-2 days. Scientific novelty and practical significance. The created catalogue of processes will allow recognizing the potential extreme situations that might be useful for middle and long-range forecasting.

scholarly journals A New Model to Downscale Urban and Rural Surface and Air Temperatures Evaluated in Shanghai, China

2018 ◽  
Vol 57 (10) ◽  
pp. 2267-2283 ◽  
Author(s):  
Dongwei Liu ◽  
C. S. B. Grimmond ◽  
Jianguo Tan ◽  
Xiangyu Ao ◽  
Jie Peng ◽  
...  
Keyword(s):  
Land Cover ◽  
Surface Temperature ◽  
Spatial Resolution ◽  
Air Temperature ◽  
Surface Air Temperature ◽  
Wave Radiation ◽  
Climate Services ◽  
Near Surface ◽  
Surface Temperatures ◽  
Air Temperatures

AbstractA simple model, the Surface Temperature and Near-Surface Air Temperature (at 2 m) Model (TsT2m), is developed to downscale numerical model output (such as from ECMWF) to obtain higher-temporal- and higher-spatial-resolution surface and near-surface air temperature. It is evaluated in Shanghai, China. Surface temperature (Ts) and near-surface air temperature (Ta) submodels account for variations in land cover and their different thermal properties, resulting in spatial variations of surface and air temperature. The net all-wave radiation parameterization (NARP) scheme is used to compute net wave radiation for the surface temperature submodel, the objective hysteresis model (OHM) is used to calculate the net storage heat fluxes, and the surface temperature is obtained by the force-restore method. The near-surface air temperature submodel considers the horizontal and vertical energy changes for a column of well-mixed air above the surface. Modeled surface temperatures reproduce the general pattern of MODIS images well, while providing more detailed patterns of the surface urban heat island. However, the simulated surface temperatures capture the warmer urban land cover and are 10.3°C warmer on average than those derived from the coarser MODIS data. For other land-cover types, values are more similar. Downscaled, higher-temporal- and higher-spatial-resolution air temperatures are compared to observations at 110 automatic weather stations across Shanghai. After downscaling with TsT2m, the average forecast accuracy of near-surface air temperature is improved by about 20%. The scheme developed has considerable potential for prediction and mitigation of urban climate conditions, particularly for weather and climate services related to heat stress.

Physiological response of swine to cycling environmental conditions

1967 ◽  
Vol 9 (4) ◽  
pp. 453-462 ◽  
Author(s):  
T. E. Bond ◽  
C. F. Kelly ◽  
H. Heitman
Keyword(s):  
Constant Temperature ◽  
Air Temperature ◽  
Environmental Conditions ◽  
Physiological Response ◽  
Respiration Rates ◽  
Surface Temperatures ◽  
Air Temperatures ◽  
Group Averaging ◽  
Maximum Air Temperature

Rectal and surface temperatures, and respiration and pulse rates, were obtained for groups of Duroc pigs that were exposed to air temperatures that varied sinusoidally over a 24-hour period. Two groups averaging 37 and 108 kg were exposed to a constant temperature of 21·1°C and then to temperatures that cycled about a mean of 21·1°C (15·6–26·7°C, 10·0–32·2°C, and 4·4–37·8°C). For a third group averaging 53 kg, the minimum was always near 21·1°C, and the maximum air temperature of the cycle was 33·2, 42·5 or 48·8°C.The response of rectal and surface temperatures, and pulse and respiration rates, to the various 24-hour cycling air temperatures are discussed and com-pared with inherent daily fluctuations in these responses that are present even when there is no variation in air temperature.

scholarly journals Construction of homogenized daily surface air temperature for the city of Tianjin during 1887–2019

2021 ◽  
Vol 13 (5) ◽  
pp. 2211-2226
Author(s):  
Peng Si ◽  
Qingxiang Li ◽  
Phil Jones
Keyword(s):  
Time Series ◽  
Air Temperature ◽  
Minimum Temperature ◽  
Surface Air Temperature ◽  
Warming Trend ◽  
Research Unit ◽  
Climatic Research Unit ◽  
Daily Maximum ◽  
Tianjin City ◽  
Monthly Journal

Abstract. Century-long continuous daily observations from some stations are important for the study of long-term trends and extreme climate events in the past. In this paper, three daily data sources – (1) the Department of Industry Agency of the British Concession in Tianjin covering 1 September 1890–31 December 1931, (2) the Water Conservancy Commission of North China covering 1 January 1932–31 December 1950 and (3) monthly journal sheets for Tianjin surface meteorological observation records covering 1 January 1951–31 December 2019 – have been collected from the Tianjin Meteorological Archive. The completed daily maximum and minimum temperature series for Tianjin from 1 January 1887 (1 September 1890 for minimum) to 31 December 2019 has been constructed and assessed for quality control with an early extension from 1890 back to 1887. Several significant breakpoints are detected by the penalized maximal T test (PMT) for the daily maximum and minimum time series using multiple reference series around Tianjin from monthly Berkeley Earth (BE), Climatic Research Unit Time-Series version 4.03 (CRU TS4.03) and Global Historical Climatology Network (GHCN) v3 data. Using neighboring daily series the record has been homogenized with quantile matching (QM) adjustments. Based on the homogenized dataset, the warming trend in annual mean temperature in Tianjin averaged from the newly constructed daily maximum and minimum temperature is evaluated as 0.154 ± 0.013 ∘C per decade during the last 130 years. Trends of temperature extremes in Tianjin are all significant at the 5 % level and have much more coincident change than those from the raw data, with amplitudes of −1.454, 1.196, −0.140 and 0.975 d per decade for cold nights (TN10p), warm nights (TN90p), cold days (TX10p) and warm days (TX90p) at the annual scale. The adjusted daily maximum, minimum and mean surface air temperature dataset for Tianjin city presented here is publicly available at https://doi.org/10.1594/PANGAEA.924561 (Si and Li, 2020).

scholarly journals Air temperature in Southern Roztochia

2015 ◽  
pp. 239-245
Author(s):  
Bohdan Mucha ◽  
Iryna Bulavenko ◽  
Oksana Rodych
Keyword(s):  
Air Temperature ◽  
Meteorological Data ◽  
Warming Trend ◽  
Annual Average ◽  
Regional Warming ◽  
Average Temperature ◽  
Air Temperatures ◽  
Average Maximum ◽  
National University

The demonstration and analysis of the monthly and annual average air temperatures in Southern Roztochia for last 46 years are proposed. The meteorological data of the Roztochia landscapegeophysical station (RLGS) of Ivan Franko National University of Lviv have served as the starting material for this publication. The long-term value of the average air temperature in RLGS has been defined. The average temperature warming by 2 °C has occurred from 1970 to 2000 and the amplitude of fluctuations of average temperatures has increased since 2000. The fact of a gradual warming trend in the region Roztochia and the adjacent Small Polissia was confirmed as an attribute of the consequences of global warming and drainage reclamation during the XX century. The graphs for annual average, maximum and minimum air temperatures for last 46 years were concluded for the duration of 5 years at the seasons. The coldest period of research is the years 1969–1989 and the warmest ones are the years since 2000 and especially 2015. The parameters of extreme warming in 2015 were fixed in agriculture and water management. We are warning about the possibility of aridization of the territory as a result of the trend of warming. The ways of preventing of regional warming due to reducing the activity of drainage reclamation systems, conservation of forest and meadow vegetation are suggested. Key words: average air temperature, regional warming, extreme air temperature, Southern Roztochia.

scholarly journals The Statistical Characteristics and Calculated Values for Air Temperature in Building`S Cladding Design

2018 ◽  
Vol 7 (3.2) ◽  
pp. 608
Author(s):  
Alla Kariuk ◽  
Oleg Koshlatyi ◽  
Roman Mishchenko
Keyword(s):  
Air Temperature ◽  
Probabilistic Approach ◽  
Thermal Inertia ◽  
Working Life ◽  
Statistical Characteristics ◽  
Effective Frequency ◽  
Distribution Law ◽  
Operating Life ◽  
Air Temperatures ◽  
Free Air

The article demonstrates the methodology and the results of statistical characteristics determination and territorial distribution as well as free air winter temperature calculated values required for the designing the building`s cladding.Daily temperatures of free air have been described by a probabilistic model of quasi-stationary differentiable random process. The expectation function is set by the Fourier series or sequence of monthly temperatures, the standard and asymmetry are determined by the mathematical expectation. The Ordinates Distribution Law is described by a linear combination of Gauss and Gumbel distributions. The frequency structure is determined by the time-constant value of the effective frequency. The required statistical characteristics are determined by the results of systematic measurements of average daily air temperature at 485 observation points inUkraine.The calculated values of winter air temperature are determined by using probabilistic approach with accounting for return period equal to building working life, as well as temperature averaging interval, reflecting building`s cladding thermal inertia. The map of territorial distribution of Ukraine has been created based on free air temperature values and dependencies which can lead to calculated values taking into account given building operating life, temperature averaging interval and altitude in mountainous regions.The developed methodology ensures the possibility of minimal calculated values determination for free air temperatures including all the factors mentioned above, and the suggestions as for introduction of norms enabling accounting for building`s cladding thermal inertia within the building working life  when making thermotechnical characteristics calculations.  

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