scholarly journals Mismatches between soil and air temperature

2021 ◽  
Author(s):  
Jonas Lembrechts ◽  
Johan van den Hoogen ◽  
Juha Aalto ◽  
Michael Ashcroft ◽  
Pieter De Frenne ◽  
...  

Research in environmental science relies heavily on global climatic grids derived from estimates of air temperature at around 2 meter above ground1-3. These climatic grids however fail to reflect conditions near and below the soil surface, where critical ecosystem functions such as soil carbon storage are controlled and most biodiversity resides4-8. By using soil temperature time series from over 8500 locations across all of the world’s terrestrial biomes4, we derived global maps of soil temperature-related variables at 1 km resolution for the 0–5 and 5–15 cm depth horizons. Based on these maps, we show that mean annual soil temperature differs markedly from the corresponding 2 m gridded air temperature, by up to 10°C, with substantial variation across biomes and seasons. Soils in cold and/or dry biomes are annually substantially warmer (3.6°C ± 2.3°C) than gridded air temperature, whereas soils in warm and humid environments are slightly cooler (0.7 ± 2.3°C). As a result, annual soil temperature varies less (by 17%) across the globe than air temperature. The effect of macroclimatic conditions on the difference between soil and air temperature highlights the importance of considering that macroclimate warming may not result in the same level of soil temperature warming. Similarly, changes in precipitation could alter the relationship between soil and air temperature, with implications for soil-atmosphere feedbacks9. Our results underpin that the impacts of climate and climate change on biodiversity and ecosystem functioning are inaccurately assessed when air rather than soil temperature is used, especially in cold environments.

1981 ◽  
Vol 61 (3) ◽  
pp. 565-573 ◽  
Author(s):  
C. A. CAMPBELL ◽  
W. NICHOLAICHUK ◽  
V. O. BIEDERBECK ◽  
H. UKRAINETZ ◽  
J. BOLE

Agronomists often require quick, easy methods of estimating soil temperatures under cereal production, either to fill in missing experimental measurements or to help explain apparent discrepancies in results. Methods available in the literature allow such estimates to be made from meteorological measurements and soil physical characteristics, but these methods are often mathematically complex. In the present paper a simple empirical regression and correlation approach was used to relate soil temperatures under cereal and fallow cropping systems to air temperature, and also to soil temperature at corresponding depths under grass plots at Swift Current, Saskatchewan. Relationships for the top 22.5 cm of soil were developed for the growing season and also for the whole year. Relationships between soil and air temperature were good near the soil surface, but deteriorated with depth even though highly significant r2 values were obtained. The best relationships were obtained between soil temperatures under the cereal system and temperatures under grass (r2 > 0.8 for growing season and > 0.9 for whole year). The relationships between mean daily temperatures under cereals (y) and those under grass at corresponding depths (x) were generally represented by y = x. The best Swift Current relationships for the growing season were used successfully [Formula: see text] to predict data for different years at Swift Current and Scott, Saskatchewan and at Lethbridge, Alberta. The error in prediction at the 10-cm depth was, on the average, 1–3 °C and at the 20-cm depth, 0–4 °C. The relationship developed will be more accurate in drier regions such as the southern prairies.


2008 ◽  
Vol 15 (3) ◽  
pp. 409-416 ◽  
Author(s):  
F. Anctil ◽  
A. Pratte ◽  
L. E. Parent ◽  
M. A. Bolinder

Abstract. The objective of this work was to compare time and frequency fluctuations of air and soil temperatures (2-, 5-, 10-, 20- and 50-cm below the soil surface) using the continuous wavelet transform, with a particular emphasis on the daily cycle. The analysis of wavelet power spectra and cross power spectra provided detailed non-stationary accounts with respect to frequencies (or periods) and to time of the structure of the data and also of the relationships that exist between time series. For this particular application to the temperature profile of a soil exposed to frost, both the air temperature and the 2-cm depth soil temperature time series exhibited a dominant power peak at 1-d periodicity, prominent from spring to autumn. This feature was gradually damped as it propagated deeper into the soil and was weak for the 20-cm depth. Influence of the incoming solar radiation was also revealed in the wavelet power spectra analysis by a weaker intensity of the 1-d peak. The principal divergence between air and soil temperatures, besides damping, occurred in winter from the latent heat release associated to the freezing of the soil water and the insulation effect of snowpack that cease the dependence of the soil temperature to the air temperature. Attenuation and phase-shifting of the 1-d periodicity could be quantified through scale-averaged power spectra and time-lag estimations. Air temperature variance was only partly transferred to the 2-cm soil temperature time series and much less so to the 20-cm soil depth.


1928 ◽  
Vol 18 (1) ◽  
pp. 90-122 ◽  
Author(s):  
E. McKenzie Taylor

1. The soil temperatures in Egypt at a number of depths have been recorded by means of continuous recording thermometers. In general, the records show that the amplitude of the temperature wave at the surface of the soil is considerably greater than the air temperature wave. There is, however, a considerable damping of the wave with depth, no daily variation in temperature being observed at a depth of 100 cm.2. No definite relation between the air and soil temperatures could be traced. The maximum air temperature was recorded in May and the maximum soil temperature in July.3. The amplitude of the temperature wave decreases with increase in depth. The decrease in amplitude of the soil temperature wave is not regular owing to variations in the physical properties of the soil layers. Between any two depths, the ratio of the amplitudes of the temperature waves is constant throughout the year. The amplitude of the soil temperature wave bears no relation to the amplitude of the air temperature wave.4. The time of maximum temperature at the soil surface is constant throughout the year at 1 p.m. The times of maximum temperature at depths below the surface lag behind the time of surface maximum, but they are constant throughout the year. When plotted against depth, the times of maximum at the various soil depths lie on a straight line.


2013 ◽  
Vol 43 (3) ◽  
pp. 209-223 ◽  
Author(s):  
Jana Krčmáŕová ◽  
Hana Stredová ◽  
Radovan Pokorný ◽  
Tomáš Stdŕeda

Abstract The aim of this study was to evaluate the course of soil temperature under the winter wheat canopy and to determine relationships between soil temperature, air temperature and partly soil moisture. In addition, the aim was to describe the dependence by means of regression equations usable for phytopathological prediction models, crop development, and yield models. The measurement of soil temperatures was performed at the experimental field station ˇZabˇcice (Europe, the Czech Republic, South Moravia). The soil in the first experimental plot is Gleyic Fluvisol with 49-58% of the content particles measuring < 0.01 mm, in the second experimental plot, the soil is Haplic Chernozem with 31-32% of the content particles measuring < 0.01 mm. The course of soil temperature and its specifics were determined under winter wheat canopy during the main growth season in the course of three years. Automatic soil temperature sensors were positioned at three depths (0.05, 0.10 and 0.20 m under soil surface), air temperature sensor in 0.05 m above soil surface. Results of the correlation analysis showed that the best interrelationships between these two variables were achieved after a 3-hour delay for the soil temperature at 0.05 m, 5-hour delay for 0.10 m, and 8-hour delay for 0.20 m. After the time correction, the determination coefficient reached values from 0.75 to 0.89 for the depth of 0.05 m, 0.61 to 0.82 for the depth of 0.10 m, and 0.33 to 0.70 for the depth of 0.20 m. When using multiple regression with quadratic spacing (modeling hourly soil temperature based on the hourly near surface air temperature and hourly soil moisture in the 0.10-0.40 m profile), the difference between the measured and the model soil temperatures at 0.05 m was −2.16 to 2.37 ◦ C. The regression equation paired with alternative agrometeorological instruments enables relatively accurate modeling of soil temperatures (R2 = 0.93).


Forests ◽  
2022 ◽  
Vol 13 (1) ◽  
pp. 74
Author(s):  
Weiwei Cong ◽  
Kaijie Yang ◽  
Feng Wang

Northern hemisphere evergreen needleleaf forest (ENF) contributes a significant fraction of global water exchange but regional transpiration (T) observation in ENF ecosystems is still challenging. Traditional remote sensing techniques and terrestrial biosphere models reproduce the transpiration seasonality with difficulty, and with large uncertainties. Solar-induced chlorophyll fluorescence (SIF) emission from vegetation correlates to photosynthesis at multiple spatial and temporal scales. However, how SIF links to transpiration of evergreen forest during seasonal transition is unclear. Here, we explored the relationship between canopy SIF and T retrieved from ground observation towers in ENF. We also examined the role of meteorological and soil factors on the relationship between SIF and T. A slow decrease of SIF and T with a fast reduction in photosynthetically active radiation (PAR), air temperature, vapor pressure deficit (VPD), soil temperature and soil water content (SWC) were found in the ENF during the fall transition. The correlation between SIF and T at hourly and daily scales varied significantly among different months (Pearson correlation coefficient = 0.29–0.68, p < 0.01). SIF and T were significantly linearly correlated at hourly (R2 = 0.53, p < 0.001) and daily (R2 = 0.67, p < 0.001) timescales in the October. Air temperature and PAR were the major moderating factors for the relationship between SIF and T in the fall transition. Soil water content (SWC) influenced the SIF-T relationship at an hourly scale. Soil temperature and VPD’s effect on the SIF-T relationship was evident at a daily scale. This study can help extend the possibility of constraining ecosystem T by SIF at an unprecedented spatiotemporal resolution during season transitions.


Author(s):  
Hui Zhang ◽  
Binhui Liu ◽  
Daowei Zhou ◽  
Zhengfang Wu ◽  
Ting Wang

Daily surface soil temperature data from 360 weather stations in China during 1962–2011 were retrieved and analyzed. The data revealed two aspects of asymmetric soil warming. Firstly, there was asymmetry between day and night in terms of increases in soil temperature. The daily maximum surface soil temperature ( S T max ) and daily minimum surface soil temperature ( S T min ) increased at rates of 0.031 and 0.055 °C/year over the 50-year interval, respectively. As a consequence of the more rapid increases in S T min , the soil diurnal temperature range (SDTR) decreased at most stations (average rate of –0.025 °C/year), with the most profound decrease in winter (–0.08 °C/year). The solar duration (SD) was positively related to SDTR and is regarded as the key underlying cause of the decreasing SDTR. Secondly, there was asymmetry between the soil and air in the temperature increase. The differences between soil and air temperature ( T D ) were highest in summer (2.76 °C) and smallest in winter (1.55 °C), which decreased by 0.3 °C over the study interval, this meant agricultural practice plans based on air temperature alone may be severely limited. The difference between soil temperature and air temperature reduces at night. This would facilitate the wintering of perennials in areas near the zero-contour line.


Agronomy ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 1973
Author(s):  
Alejandro López-Martínez ◽  
Francisco D. Molina-Aiz ◽  
María de los Ángeles Moreno-Teruel ◽  
Araceli Peña-Fernández ◽  
Fátima J. F. Baptista ◽  
...  

The main objective of this work was to analyze the microclimate generated inside a low tunnel (floating row cover) installed in an Almería-type greenhouse. Low tunnels are commonly used in the open field to protect plants against insect attack and to improve the production of muskmelon and strawberry. Floating row covers can also be used inside greenhouses during the first few weeks after the transplantation of muskmelon and watermelon crops in spring-summer cycles. This work was carried out during the first weeks of a watermelon culture (Citrullus lanatus Thunb.) growing with a polyethylene row cover inside an Almería-type greenhouse (2115 m2). Air temperature and humidity, plant temperature and soil temperature and humidity were measured in the greenhouse inside and outside the row covers. During the three days of measurement, all greenhouse vent openings were closed. The use of the low tunnels increased average air temperature around plants from 24.0 ± 9.0 °C to 26.9 ± 9.7 °C. A maximum difference in air temperature of about 5.9 °C was observed at noon. The average daily temperature of the crop was 28.2 ± 11.8 °C inside the row cover and 24.6 ± 8.9 °C without it. Similarly, the absolute humidity of air was clearly higher inside the low tunnel (0.0201 ± 0.0098 g/g) than around the plant rows without floating cover (0.0131 ± 0.0048 g/g). The soil temperature was also higher inside the low tunnel compared to the area without this second plastic cover. The effect of the tunnel decreased with depth, with average temperature differences of 1.2 ± 0.5 °C on the soil surface and 0.6 ± 0.5 °C at 20 cm depth.


1980 ◽  
Vol 60 (2) ◽  
pp. 299-309 ◽  
Author(s):  
A. REIMER ◽  
C. F. SHAYKEWICH

Soil-temperature studies were conducted under forage and zero tillage conditions at the Whiteshell Nuclear Research Establishment (WNRE), Pinawa, Manitoba, as part of the plant radiation ecology research program. The objective was to develop estimation equations for monthly mean and daily mean soil surface temperatures from atmospheric meteorological measurements. Subsoil temperatures were estimated from predicted soil surface temperatures by applying an appropriate damping factor. Monthly mean soil surface temperatures were estimated for summer and winter months from regression equations with meteorological predictors. Daily mean soil surface temperatures were predicted from regression equations with meteorological predictors combined with best-fit Fournier-series seasonal curves. Daily mean subsoil temperatures at 10 cm were estimated from predicted soil surface temperatures by applying an appropriate damping factor. The standard deviation of the difference between predicted and observed temperatures was generally less than 1 °C for daily and monthly estimates. A good estimate of the seasonal subsoil temperature at 10, 50, 100 and 200 cm was found from a periodic function with damping and phase paramaters. The explained variance was 95% or more. With appropriate assumptions regarding soil thermal properties and mean annual soil temperature, accurate results were obtained quickly and economically.


2010 ◽  
Vol 29 (1) ◽  
pp. 5-12 ◽  
Author(s):  
Ewa Bednorz ◽  
Leszek Kolendowicz

Daily course of the soil temperature in summer in chosen ecosystems of Słowiński National Park, northern Poland Patterns of the daily changes of the soil temperature in summer at three different ecosystems within the Słowiński National Park were analyzed. Strong correlation between the solar radiation and the soil temperature was found, particularly for the bare sandy surfaces, while the plant and humus cover hampers the solar energy flux to the soil. In the same way, correlations between the temperature of soil surface and the air temperature were computed. Finally, logarithmic models for the relationship between the global solar radiation and the soil surface temperature and between the soil surface temperature and the air temperature were constructed.


1998 ◽  
Vol 7 (4) ◽  
pp. 507-512 ◽  
Author(s):  
M. YLI-HALLA ◽  
D. MOKMA

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.;


Sign in / Sign up

Export Citation Format

Share Document