Transient high temperatures during seed growth in narrow-leafed lupin (Lupinus angustifolius L.) II. Injuriously high pod temperatures are likely in Western Australia

1997 ◽  
Vol 48 (8) ◽  
pp. 1179 ◽  
Author(s):  
M. A. Reader ◽  
M. Dracup ◽  
C. A. Atkins
Keyword(s):  
High Temperatures ◽  
Air Temperature ◽  
Western Australia ◽  
Meteorological Data ◽  
Grain Filling ◽  
Lupinus Angustifolius ◽  
Trickle Irrigation ◽  
Seed Filling ◽  
Air Temperatures ◽  
The Difference

Studies under controlled environment conditions indicate that transient high temperatures (34-38˚C) during grain filling can significantly reduce weight per seed in narrow-leafed lupin (Lupinus angustifolius L.). This study has shown that on average, lupin pods reach temperatures about 3-5˚C higher than the maximum daily air temperature during seed filling under field cropping conditions. These differences do not appear to be markedly influenced by the amount of radiation intercepted by the canopy, stage of pod development, or position of the pods in the canopy, but fluctuate more as a result of differences in radiation intensity, wind speed, and water availability. Trickle irrigation reduced the difference between pod and air temperature by about 2˚C. Lupin species with larger pods (L. cosentinii and L. atlanticus) reached higher maximum daily temperatures than those of L. angustifolius. Long-term meteorological data indicate that air temperatures during seed filling of lupins in Western Australia are likely to exceed 30˚ C and will occasionally exceed 35˚ C. In lupin-growing areas of Western Australia, pod temperatures exceeding 33-35˚ C can be expected about 1 year in every 3, and more rarely (about 1 in 10 years), pod temperatures exceeding 38-40˚ C can be expected. These transient high temperatures are likely to increase significantly the year to year variation in yields of lupin grain.

The Influence of Uncertainty in Air Temperature and Albedo on Snowmelt

1991 ◽  
Vol 22 (2) ◽  
pp. 95-108 ◽  
Author(s):  
G. Blöschl
Keyword(s):  
Snow Cover ◽  
Air Temperature ◽  
Meteorological Data ◽  
Model Parameters ◽  
Local Effects ◽  
Austrian Alps ◽  
Air Temperatures ◽  
Basin Scale ◽  
Simulation Results

Extrapolating meteorological data to the basin scale represents a major problem of spatial snowmelt modelling in alpine terrain. Within this study errors in air temperature introduced by regionalization are analyzed for the Sellrain region in the Austrian Alps. Albedo is simulated using a range of model parameters representing different snow cover conditions. The influence on snowmelt is assessed by simulating water equivalent at the site scale using estimated air temperatures and albedoes. Simulation results indicate that a bias in measured temperatures as produced by local effects may be significantly more important than interpolation errors. Uncertainty in albedo appears to affect snowmelt to a higher degree than air temperature.

Rail Temperature Approximation and Heat Slow Order Best Practices

2015 ◽  
Author(s):  
Radim Bruzek ◽  
Michael Trosino ◽  
Leopold Kreisel ◽  
Leith Al-Nazer
Keyword(s):  
Air Temperature ◽  
Geographical Location ◽  
Ambient Air ◽  
Temperature Threshold ◽  
Eastern United States ◽  
Ambient Air Temperature ◽  
Air Temperatures ◽  
The Difference ◽  
Temperature Offset ◽  
Environmental Prediction

The railroad industry uses slow orders, sometimes referred to as speed restrictions, in areas where an elevated rail temperature is expected in order to minimize the risk and consequence of derailment caused by track buckling due to excessive rail temperature. Traditionally, rail temperature has been approximated by adding a constant offset, most often 30°F, to a peak ambient air temperature. When this approximated maximum rail temperature exceeds a given risk threshold, slow orders are usually issued for a predefined period of the day. This “one size fits all” approach, however, is not effective and suitable in all situations. On very warm days, the difference between rail temperature and ambient air temperature can exceed railroad-employed offsets and remain elevated for extended periods of time. A given temperature offset may be well suited for certain regions and track buckling risk-related rail temperature thresholds but less accurate for others. Almost 160,000 hours of rail temperature measurements collected in 2012 across the eastern United States by two Class I railroads and predicted ambient air temperatures based on the National Weather Service’s National Centers for Environmental Prediction (NCEP) data were analyzed using detection theory in order to establish optimal values of offsets between air and rail temperatures as well as times when slow orders should be in place based on geographical location and the track buckling risk rail temperature threshold. This paper presents the results of the analysis and describes an improved procedure to manage heat-related slow orders based on ambient air temperatures.

scholarly journals Cool Pavement Strategies for Urban Heat Island Mitigation in Suburban Phoenix, Arizona

2019 ◽  
Vol 11 (16) ◽  
pp. 4452 ◽  
Author(s):  
Sushobhan Sen ◽  
Jeffery Roesler ◽  
Benjamin Ruddell ◽  
Ariane Middel
Keyword(s):  
Urban Heat Island ◽  
Air Temperature ◽  
Urban Areas ◽  
Meteorological Data ◽  
Heat Island ◽  
Land Use Patterns ◽  
Reflective Coating ◽  
Air Temperatures ◽  
Artificial Surfaces ◽  
Urban Heat

Urban areas are characterized by a large proportion of artificial surfaces, such as concrete and asphalt, which absorb and store more heat than natural vegetation, leading to the Urban Heat Island (UHI) effect. Cool pavements, walls, and roofs have been suggested as a solution to mitigate UHI, but their effectiveness depends on local land-use patterns and surrounding urban forms. Meteorological data was collected using a mobile platform in the Power Ranch community of Gilbert, Arizona in the Phoenix Metropolitan Area, a region that experiences harsh summer temperatures. The warmest hour recorded during data collection was 13 August 2015 at 5:00 p.m., with a far-field air temperature of about 42 ∘ C and a low wind speed of 0.45 m/s from East-Southeast (ESE). An uncoupled pavement-urban canyon Computational Fluid Dynamics (CFD) model was developed and validated to study the microclimate of the area. Five scenarios were studied to investigate the effects of different pavements on UHI, replacing all pavements with surfaces of progressively higher albedo: New asphalt concrete, typical concrete, reflective concrete, making only roofs and walls reflective, and finally replacing all artificial surfaces with a reflective coating. While new asphalt surfaces increased the surrounding 2 m air temperatures by up to 0.5 ∘ C, replacing aged asphalt with typical concrete with higher albedo did not significantly decrease it. Reflective concrete pavements decreased air temperature by 0.2–0.4 ∘ C and reflective roofs and walls by 0.4–0.7 ∘ C, while replacing all roofs, walls, and pavements with a reflective coating led to a more significant decrease, of up to 0.8–1.0 ∘ C. Residences downstream of major collector roads experienced a decreased air temperature at the higher end of these ranges. However, large areas of natural surfaces for this community had a significant effect on downstream air temperatures, which limits the UHI mitigation potential of these strategies.

Skin folds and Merino breeding. 5. Variations in scrotal, testis, and rectal temperatures as affected by site of measurement, acclimatization to heat and degree of skin fold

1968 ◽  
Vol 8 (31) ◽  
pp. 125 ◽  
Author(s):  
DG Fowler
Keyword(s):  
High Temperatures ◽  
Air Temperature ◽  
Heat Tolerance ◽  
Temperature Regime ◽  
Low Temperatures ◽  
Air Temperatures ◽  
Skin Fold ◽  
Fold Type

In Merino rams, subcutaneous temperature in the scrotum declined from the inguinal border to the distal tip and from posterior to anterior. Testicular temperature was similar at several sites in both testes. Of the total increase in scrotal and testicular temperatures that occurred when rams were heated, the proportional hourly increases were similar at each air temperature above 30�C irrespective of the air temperature regime (stepwise increasing or stepwise decreasing air temperatures) or fold type of the ram. The response of rams depended markedly on the air temperature regime. When air temperatures were decreasing, rams were less able to withstand high temperatures and more able to withstand low temperatures. When air temperatures were increasing the reverse was true. The differences between Folds Plus and Folds Minus rams also depended markedly on the ail temperature regime. In general Folds Minus rams had lower rectal temperatures than Folds Plus rams, but could express their ability to maintain lower subcutaneous scrotal temperatures than Folds Plus rams only after they had gained a degree of acclimatization to heat. Folds Plus rams had higher food intakes than Folds Minus rams which may be a factor in their reduced heat tolerance.

Season and ambient air temperature influence the distribution of mites (Proctophyllodes stylifer) across the wings of blue tits (Parus caeruleus)

2000 ◽  
Vol 78 (8) ◽  
pp. 1397-1407 ◽  
Author(s):  
P R Wiles ◽  
J Cameron ◽  
J M Behnke ◽  
I R Hartley ◽  
F S Gilbert ◽  
...  
Keyword(s):  
Air Temperature ◽  
Meteorological Data ◽  
Ambient Air ◽  
Parus Caeruleus ◽  
Wing Feather ◽  
Ambient Air Temperature ◽  
Air Temperatures ◽  
West Midlands ◽  
Study Sites ◽  
Blue Tits

Changes in the distribution of the wing-feather mite Proctophyllodes stylifer (Buckholz 1869) on the flight feathers of blue tits (Parus caeruleus) were studied throughout the seasons and in relation to ambient air temperature at three combinations of study sites (Lancashire, West Midlands, and South Midlands). We tested the hypotheses that the distribution of mites is influenced in part by season and ambient air temperature. In the winter months mites clustered predominantly on the tertiary feathers, whereas in late spring, summer, and autumn, mite-infestation scores were higher on the proximal primary and secondary feathers. Three approaches were employed to determine whether this seasonal redistribution of mites arose as a response to changes in microclimate, probably ambient air temperature, rather than to season per se. Firstly, meteorological data for the Lancashire study sites, and our own monitoring of the precise air temperature at the time of handling and inspection at the West Midlands study sites, enabled us to establish a link between distribution pattern and ambient temperature. Secondly, limited observations on the distribution of mites on birds recaptured when ambient air temperatures differed by 5°C or more between first and second nettings, one temperature being below 10°C and the other above, supported the idea that the change in distribution was associated with air temperature. Finally, the results of a small experiment in which heavily infested birds caught on a day when air temperatures ranged from 9 to 11°C were taken indoors and temporarily subjected to a higher ambient air temperature (20 min) prior to re-inspection and release also confirmed that mite movement was associated with the temperature of their environment. We conclude that the seasonal changes in distribution were driven by microclimatic changes, in part by temperature.

scholarly journals Analysis of the Spatio-Temporal Variability of Air Temperature Near the Ground Surface in the Central Baltic Area from 2005 to 2019

Atmosphere ◽  
2020 ◽  
Vol 12 (1) ◽  
pp. 60
Author(s):  
Agu Eensaar
Keyword(s):  
Air Temperature ◽  
Ground Surface ◽  
Surface Air Temperature ◽  
Entire Study ◽  
Significance Level ◽  
Average Surface ◽  
Air Temperatures ◽  
Spatio Temporal ◽  
The Difference ◽  
Baltic Area

In this study, we analyzed the changes in the average daily, monthly, seasonal, and annual surface air temperatures based on the temperature data obtained from seven stations (1 January 2005–31 December 2019; 15 years) belonging to the central Baltic area (Stockholm, Tallinn, Helsinki, Narva, Pärnu, Tartu, and Võru). The statistical analysis revealed that there was a strong correlation between the daily average surface air temperature of the studied cities (range: 0.95–0.99). We analyzed the frequency distribution of the average surface air temperatures in addition to the Kruskal–Wallis and Dunn’s tests (significance level of 0.05) to demonstrate that the difference in air temperatures between Narva, Tallinn, Tartu, and Stockholm are critical. The Welch’s t-test (significance level 0.05), used to study the differences in the average monthly air temperature of the cities in question, showed that the surface air temperatures in Stockholm do not differ from Tallinn air temperatures from May to August. However, the surface air temperatures of Narva were similar to those of Tallinn in September. According to our results, the trends in the changes of monthly average surface air temperatures have a certain course during the year (ranging from 1.8 °C (Stockholm) to 4.5 °C (Võru and Tartu) per decade in February). During the entire study period, in addition to February, the surface air temperature increased in all the studied cities in March, May, June, and December, and the surface air temperature did not increase in January or from July to October. During the study period, the average annual surface air temperature in the cities of the central Baltic area increased by 0.43 °C per decade. The results also confirm that the surface air temperature in the study area is changing differently in different cities. The acceleration of the surface air temperature is very alarming and requires a significant intensification of the measures taken to slow down the temperature rise.

scholarly journals A Temperature Index Model to Estimate Long-term Freeze-risk of Satsuma Mandarins Grown on the Northern Coast of the Gulf of Mexico

2005 ◽  
Vol 130 (4) ◽  
pp. 500-507 ◽  
Author(s):  
R.C. Ebel ◽  
B.L. Campbell ◽  
M.L. Nesbitt ◽  
W.A. Dozier ◽  
J.K. Lindsey ◽  
...  
Keyword(s):  
Air Temperature ◽  
Cold Hardiness ◽  
Management Practices ◽  
Rating Scale ◽  
Daily Maximum ◽  
Northern Coast ◽  
Freeze Injury ◽  
Air Temperatures ◽  
The Difference

Estimates of long-term freeze-risk aid decisions regarding crop, cultivar, and rootstock selection, cultural management practices that promote cold hardiness, and methods of freeze protection. Citrus cold hardiness is mostly a function of air temperature, but historical weather records typically contain only daily maximum (Tmax) and minimum (Tmin) air temperatures. A mathematical model was developed that used Tmax and Tmin to estimate air temperature every hour during the diurnal cycle; a cold-hardiness index (CHI500) was calculated by summing the hours ≤10°C for the 500 h before each day; and the CHI500 was regressed against critical temperatures (Tc) that cause injury. The CHI500 was calculated from a weather station located within 0.1 km of an experimental grove and in the middle of the satsuma mandarin (Citrus unshiu Marc.) industry in southern Alabama. Calculation of CHI500 was verified by regressing a predicted CHI500 using Tmax and Tmin, to a measured CHI500 calculated using air temperatures measured every hour for 4 winter seasons (1999-2003). Predicted CHI500 was linearly related to measured CHI500 (r2 = 0.982). However, the slope was a little low such that trees with a CHI500 = 400, near the maximum cold-hardiness level achieved in this study, had predicted Tc that was 0.5 °C lower than measured Tc. Predicted and measured Tc were similar for nonhardened trees (CHI500 = 0). The ability of predicted Tc to estimate freeze injury was determined in 18 winter seasons where freeze injury was recorded. During injurious freeze events, predicted Tc was higher than Tmin except for a freeze on 8 Mar. 1996. In some freezes where the difference in Tc and Tmin was <0.5 °C there were no visible injury symptoms. Injury by the freeze on 8 Mar. 1996 was due, in part, to abnormally rapid deacclimation because of defoliation by an earlier freeze on 4-6 Feb. the same year. A freeze rating scale was developed that related the difference in Tc and Tmin to the extent of injury. Severe freezes were characterized by tree death (Tc - Tmin > 3.0 °C), moderate freezes by foliage kill and some stem dieback (1.0 °C ≤ Tc - Tmin ≤ 3.0 °C), and slight freezes by slight to no visible leaf injury (Tc - Tmin < 1.0 °C). The model was applied to Tmax and Tmin recorded daily from 1948 through 2004 to estimate long-term freeze-risk for economically damaging freezes (severe and moderate freeze ratings). Economically damaging freezes occurred 1 out of 4 years in the 56-year study, although 8 of the 14 freeze years occurred in two clusters, the first 5 years in the 1960s and 1980s. Potential modification of freeze-risk using within-tree microsprinkler irrigation and more cold-hardy cultivars was discussed.

scholarly journals Temperaturna odvisnost razgradnje opada v tleh travnikov v zaraščanju

2018 ◽  
Vol 111 (1) ◽  
pp. 189
Author(s):  
Marjetka SUHADOLC ◽  
Zalika ČREPINŠEK
Keyword(s):  
Mass Loss ◽  
Litter Decomposition ◽  
Air Temperature ◽  
Decomposition Rate ◽  
Lignin Content ◽  
Plant Litter ◽  
Litter Bags ◽  
Plant Litter Decomposition ◽  
Air Temperatures ◽  
The Difference

The aim of the study was to examine whether the effect of projected temperature rises due to the global climate change could accelerate plant litter decomposition in soils of overgrown grasslands. The experiment was carried out under natural conditions at the locations of Bohinj-Polje and Uskovnica with similar environmental conditions (precipitation, parent material and soil development, plant communities) and the difference in air temperatures. The average difference in monthly air temperatures during our study were higher in Bohinj for 4.4 °C (± 1.5 °C) than in Uskovnica. Nylon mesh bags with mixed plant litter from both locations were placed into the Of horizon of the soil profiles at both locations in autumn 2007. The litter bags were sampled successively at 4 sampling times until May 2009 in 5 replicates. The litter degradation, expressed as mass loss, was throughout our study 57.1 ± 1.2 % (0 - 526 days) in Bohinj, 57.3 ± 2.6 % (0 - 555 days) at Uskovnica. No statistically significant differences in litter decomposition rate and seasonal pattern of mass loss was found between the sites. The dynamics of the total content of cellulose and lignin, Corg and N and their soluble forms (DOC and DON) were similar between the sites as well. The lignin content in the plant material did not statistically significantly change during the experiment. The results of our experiment did not confirm the effect of the difference in average air temperature on decomposition rate decreases. The results did not confirm any effect from the difference in the average monthly air temperature between the sites on the plant litter decomposition in our study.

scholarly journals EVALUATION OF A HEATING SYSTEM WITH A HEAT PUMP ACCORDING TO THE MODE OF INPUT DATA

2015 ◽  
Vol 1 (2) ◽  
pp. 65-71
Author(s):  
Vladimíra Linhartová
Keyword(s):  
Heat Pump ◽  
Air Temperature ◽  
Input Data ◽  
Heating System ◽  
Temperature Data ◽  
Air Source Heat Pump ◽  
Air Temperatures ◽  
The Difference ◽  
Bin Method

The paper is focused on evaluating a heating system with an air source heat pump using the bin method. The main goal of the paper is to find the difference between three modes of input outside air temperature data in the calculation. Outside air temperatures are used in three modes, an hour based calculation, monthly frequencies and annual frequencies based calculations.

Increasing phosphorus concentration in lupin seed increases grain yield on phosphorus deficient soil

1989 ◽  
Vol 29 (6) ◽  
pp. 797 ◽  
Author(s):  
MDA Bolland ◽  
BH Paynter ◽  
MJ Baker
Keyword(s):  
Field Experiment ◽  
Grain Yield ◽  
Western Australia ◽  
Dry Matter ◽  
Lupinus Angustifolius ◽  
Phosphorus Concentration ◽  
Grain Yields ◽  
P Concentration ◽  
Lupin Seed ◽  
The Difference

In a field experiment on a phosphorus (P) deficient soil in south-western Australia, lupin seed (Lupinus angustifolius cv. Danja) of the same size (157 mg/seed) but with 2 different phosphorus (P) concentrations in the seed (2.0 and 2.8 g P/kg) was sown with 4 levels of superphosphate (5, 20, 40 and 60 kg P/ha) drilled with the seed in May 1988 to examine the effect of seed P concentration on subsequent dry matter (DM) and grain yields. Increasing the amount of superphosphate applied from 5 to 60 kg P/ha almost doubled yields. In addition, lupins grown from seed containing the higher P concentration produced larger yields of dried whole tops in early August (69-day-old) for all levels of superphosphate drilled with the seed, the difference decreasing from about 45 to 10% as the level of superphosphate increased from 5 to 60 kg P/ha. By maturity (mid- November), however, plants grown from seed containing the higher P concentration in seed produced higher DM yields of tops and grain only when 5 and 20 kg P/ha superphosphate was drilled with the seed, the differences being about 40 and 20%, respectively.

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