Temporal variability of ground thermal regimes on the northern buttress of the Vesleskarvet nunatak, western Dronning Maud Land, Antarctica

AbstractThe ground temperature down to 60 cm depth in western Dronning Maud Land (WDML), has been recorded since 2009. The study area is situated in a blockfield that comprises a shallow active layer above permafrost. Using ground thermal regimes and regional climate data, the temporal (seasonal and annual) variability of the active layer was characterized. Active layer depth was calculated for each site for five consecutive summers from 2009/10–2013/14, showing interannual variability with no overall trends of decreasing or increasing active layer depth. Particular attention was paid to 2010 as it matched the average for the ground thermal regimes over the six year study period, as well as the interpolation period used by Meteonorm®. Analysis showed significant synchronous relationships of ground thermal regimes with air temperature and incoming radiation. Moreover, a correlation between pressure and measured ground temperature during the transitional season of the Southern Annual Oscillation in May and September was identified.

Download Full-text

Permafrost and active layer research on James Ross Island: An overview

Czech Polar Reports ◽

10.5817/cpr2019-1-3 ◽

2019 ◽

Vol 9 (1) ◽

pp. 20-36 ◽

Cited By ~ 3

Author(s):

Filip Hrbáček ◽

Daniel Nývlt ◽

Kamil Láska ◽

Michaela Kňažková ◽

Barbora Kampová ◽

...

Keyword(s):

Thermal Conductivity ◽

Layer Thickness ◽

Active Layer ◽

Air Temperature ◽

Thermal Regime ◽

Ground Temperature ◽

Active Layer Thickness ◽

Near Surface ◽

James Ross Island ◽

The Mean

This study summarizes the current state of the active layer and permafrost research on James Ross Island. The analysis of climate parameters covers the reference period 2011–2017. The mean annual air temperature at the AWS-JGM site was -6.9°C (ranged from -3.9°C to -8.2°C). The mean annual ground temperature at the depth of 5 cm was -5.5°C (ranged from -3.3°C to -6.7°C) and it also reached -5.6°C (ranged from -4.0 to -6.8°C) at the depth of 50 cm. The mean daily ground temperature at the depth of 5 cm correlated moderately up to strongly with the air temperature depending on the season of the year. Analysis of the snow effect on the ground thermal regime confirmed a low insulating effect of snow cover when snow thickness reached up to 50 cm. A thicker snow accumulation, reaching at least 70 cm, can develop around the hyaloclastite breccia boulders where a well pronounced insulation effect on the near-surface ground thermal regime was observed. The effect of lithology on the ground physical properties and the active layer thickness was also investigated. Laboratory analysis of ground thermal properties showed variation in thermal conductivity (0.3 to 0.9 W m-1 K-1). The thickest active layer (89 cm) was observed on the Berry Hill slopes site, where the lowest thawing degree days index (321 to 382°C·day) and the highest value of thermal conductivity (0.9 W m-1 K-1) was observed. The clearest influence of lithological conditions on active layer thickness was observed on the CALM-S grid. The site comprises a sandy Holocene marine terrace and muddy sand of the Whisky Bay Formation. Surveying using a manual probe, ground penetrating radar, and an electromagnetic conductivity meter clearly showed the effect of the lithological boundary on local variability of the active layer thickness.

Download Full-text

Climate Change and Its Influence on the Active Layer Depth in Central Yakutia

Land ◽

10.3390/land10010003 ◽

2020 ◽

Vol 10 (1) ◽

pp. 3

Author(s):

Alexey Desyatkin ◽

Pavel Fedorov ◽

Nikolay Filippov ◽

Roman Desyatkin

Keyword(s):

Active Layer ◽

Air Temperature ◽

Arable Land ◽

Winter Season ◽

Climatic Conditions ◽

Layer Depth ◽

Central Yakutia ◽

Negative Temperatures ◽

Permafrost Soils ◽

High Dynamics

Analysis of climatic conditions for the period of instrumental measurement in Central Yakutia showed three periods with two different mean annual air temperature (MAAT) shifts. These periods were divided into 1930–1987 (base period A), 1988–2006 (period B) and 2007–2018 (period C) timelines. The MAAT during these three periods amounted −10.3, −8.6 and −7.4 °C, respectively. Measurement of active layer depth (ALD) of permafrost pale soil under the forest (natural) and arable land (anthropogenic) were carried out during 1990–2018 period. MAAT change for this period affected an early transition of negative temperatures to positive and a later establishment of negative temperatures. Additionally, a shortening of the winter season and an extension of the duration of days with positive temperatures was found. Since the permafrost has a significant impact on soil moisture and thermal regimes, the deepening of ALD plays a negative role for studied soils. An increase in the ALD can cause thawing of underground ice and lead to degradation of the ice-rich permafrost. This thaw process causes a change of the ecological balance and leads to the destruction of natural landscapes, sometimes with a complete or prolonged loss of their biological productivity. During this observation (1990–2018 period) the active layer of permafrost is characterized by high dynamics, depending on climatic parameters such as air temperature, as well as thickness and duration of snow cover. A significant increase in ALD of forest permafrost soils—by 80 cm and 65 cm—on arable land was measured during the observation period (28 years).

Download Full-text

Spatio‐temporal variability of summer monsoon surface air temperature over India and its regions using Regional Climate Model

International Journal of Climatology ◽

10.1002/joc.7155 ◽

2021 ◽

Author(s):

Shruti Verma ◽

R. Bhatla ◽

S. Ghosh ◽

Palash Sinha ◽

R.K. Mall ◽

...

Keyword(s):

Regional Climate Model ◽

Air Temperature ◽

Summer Monsoon ◽

Temporal Variability ◽

Climate Model ◽

Regional Climate ◽

Surface Air Temperature ◽

Its Regions ◽

Spatio Temporal

Download Full-text

Independent validation of downscaled climate estimates from a coastal Alaska watershed using local historical weather journals

PeerJ ◽

10.7717/peerj.12055 ◽

2021 ◽

Vol 9 ◽

pp. e12055

Author(s):

Emily R. Williamson ◽

Christopher J. Sergeant

Keyword(s):

Time Series ◽

Air Temperature ◽

Empirical Data ◽

Climate Models ◽

Regional Climate ◽

Data Sources ◽

Mean Annual Precipitation ◽

Monthly Precipitation ◽

Grid Cells ◽

Climate Data

Downscaling coarse global and regional climate models allows researchers to access weather and climate data at finer temporal and spatial resolution, but there remains a need to compare these models with empirical data sources to assess model accuracy. Here, we validate a widely used software for generating North American downscaled climate data, ClimateNA, with a novel empirical data source, 20th century weather journals kept by Admiralty Island, Alaska homesteader, Allen Hasselborg. Using Hasselborg’s journals, we calculated monthly precipitation and monthly mean of the maximum daily air temperature across the years 1926 to 1954 and compared these to ClimateNA data generated from the Hasselborg homestead location and adjacent areas. To demonstrate the utility and potential implications of this validation for other disciplines such as hydrology, we used an established regression equation to generate time series of 95% low duration flow estimates for the month of August using mean annual precipitation from ClimateNA predictions and Hasselborg data. Across 279 months, we found strong correlation between modeled and observed measurements of monthly precipitation (ρ = 0.74) and monthly mean of the maximum daily air temperature (ρ = 0.98). Monthly precipitation residuals (calculated as ClimateNA data - Hasselborg data) generally demonstrated heteroscedasticity around zero, but a negative trend in residual values starting during the last decade of observations may have been due to a shift to the cold-phase Pacific Decadal Oscillation. Air temperature residuals demonstrated a consistent but small positive bias, with ClimateNA tending to overestimate air temperature relative to Hasselborg’s journals. The degree of correlation between weather patterns observed at the Hasselborg homestead site and ClimateNA data extracted from spatial grid cells across the region varied by wet and dry climate years. Monthly precipitation from both data sources tended to be more similar across a larger area during wet years (mean ρ across grid cells = 0.73) compared to dry years (mean ρ across grid cells = 0.65). The time series of annual 95% low duration flow estimates for the month of August generated using ClimateNA and Hasselborg data were moderately correlated (ρ = 0.55). Our analysis supports previous research in other regions which also found ClimateNA to be a robust source for past climate data estimates.

Download Full-text

Climatic controls on active layer dynamics: Amsler Island, Antarctica

Antarctic Science ◽

10.1017/s0954102016000511 ◽

2016 ◽

Vol 29 (2) ◽

pp. 173-182 ◽

Cited By ~ 1

Author(s):

Kelly R. Wilhelm ◽

James G. Bockheim

Keyword(s):

Solar Radiation ◽

Snow Cover ◽

Active Layer ◽

Air Temperature ◽

Ground Surface ◽

Ground Temperature ◽

Seasonal Temperature ◽

Atmospheric Conditions ◽

Temperature Variations ◽

Ground Temperatures

AbstractVariations in atmospheric conditions can be important factors influencing temperature dynamics within the active layer of a soil. Solar radiation and air temperature can directly alter ground surface temperatures, while variations in wind and precipitation can control how quickly heat is carried through soil pores. The presence of seasonal snow cover can also create a thermal barrier between the atmosphere and ground surface. This study examines the relation between atmospheric conditions and ground temperature variations on a deglaciated island along the Western Antarctic Peninsula. Ground temperatures were most significantly influenced by incoming solar radiation, followed by air temperature variations. When winter months were included in the comparison, the influence of air temperature increased while solar radiation became less influential, indicating that snow cover reflected solar radiation inputs, but was not thick enough to insulate the ground. When ground temperatures were compared to atmospheric conditions of preceding weeks, seasonal temperature peaks 1.6 m below ground were best related to seasonal air temperature peaks from the previous two weeks. The same ground temperature peaks were best related to seasonal solar radiation peaks of seven weeks prior. This difference was a result of temperature lags within the atmosphere.

Download Full-text

Spatial and temporal variability in summer snow pack in Dronning Maud Land, Antarctica

The Cryosphere ◽

10.5194/tc-5-187-2011 ◽

2011 ◽

Vol 5 (1) ◽

pp. 187-201 ◽

Cited By ~ 9

Author(s):

T. Vihma ◽

O.-P. Mattila ◽

R. Pirazzini ◽

M. M. Johansson

Keyword(s):

Standard Deviation ◽

Air Temperature ◽

Temporal Variability ◽

Field Measurements ◽

Spatial And Temporal Variability ◽

Snow Pack ◽

Snow Density ◽

Annual Variations ◽

Dronning Maud Land ◽

Snow Temperature

Abstract. To quantify the spatial and temporal variability in the snow pack, field measurements were carried out during four summers in Dronning Maud Land, Antarctica. Data from a 310-km-long transect revealed the largest horizontal gradients in snow density, temperature, and hardness in the escarpment region. On the local scale, day-to-day temporal variability dominated the standard deviation of snow temperature, while the diurnal cycle was of second significance, and horizontal variability on the scale of 0.4 to 10 m was least important. In the uppermost 0.2 m, the snow temperature was correlated with the air temperature over the previous 6–12 h, whereas at the depths of 0.3 to 0.5 m the most important time scale was 3 days. Cloud cover and radiative fluxes affected the snow temperature in the uppermost 0.30 m and the snow density in the uppermost 0.10 m. Both on the intra-pit and transect scales, the ratio of horizontal to temporal variability increased with depth. The horizontal standard deviation of snow density increased rapidly between the scales of 0.4 and 2 m, and more gradually from 10 to 100 m. Inter-annual variations in snow temperature and density were due to inter-annual differences in air temperature and the timing of the precipitation events.

Download Full-text

Evaluation of future trends of characteristics change of hydrological regime of rivers of the Southern Buh basin in the winter period

Ukrainian hydrometeorological journal ◽

10.31481/uhmj.20.2017.11 ◽

2017 ◽

pp. 91-98

Author(s):

E. R. Rachmatullina ◽

V. V. Grebin

Keyword(s):

Air Temperature ◽

Climate Changes ◽

Climate Model ◽

Regional Climate ◽

Surface Air Temperature ◽

Hydrological Regime ◽

Winter Period ◽

Thermal Regimes ◽

Global Surface ◽

Surface Air Layer

Introduction. Climate changes occurring in recent decades determine the relevance of the problem of forecasting such changes in future both globally and regionally. After all, knowledge of climate's behavior in future is very important when carrying out an analysis of trends of hydrological characteristics change. Significant increase of the global surface air temperature observed since the end of the 20th century is mainly caused by increase of concentration of greenhouse gases generated as a result of industrial activity. Thus, climate changes could not but affect the continental water resources and in particular the processes taking place in rivers. Purpose. Assessment of change of surface air layer during the winter period within the South-ern Buh Basin and assessment of change of the hydrological regime of the basin's rivers following the changes of air temperature. Methods of research. This study is based on the data for the winter period obtained from 24 hydrological station and 15 meteorological stations within the Southern Buh River Basin. With assistance of scientists of the Ukrainian Hydrometeorological Institute and using the regional climate model REMO for A1B scenario forecast values of air temperature were calculated. Results of research. The main regularities of studied characteristics change for the period of 2031-2050 were determined on the basis of prepared calculation dependences of the characteristics of ice and thermal regimes of the studied basin's rivers and obtained forecast values of air temperature. According to the climatologists' calculations there is a tendency of air temperature increase during the forecast period, and, respectively, increase of water temperature and decrease of ice period duration of the rivers within the Southern Buh Basin. Summary (conclusions and author's recommendations). The results of the carried out research indicate the fact that the trend of increase of surface air layer temperature and change of main characteristics of ice and thermal regimes of the basin's rivers formed at the end of 20th - the beginning of the 21th century will develop in future.

Download Full-text

VARIABILIDADE TEMPORAL E MAPEAMENTO DOS DADOS CLIMÁTICOS DE BOTUCATU–SP

Irriga ◽

10.15809/irriga.2010v15n2p131 ◽

2010 ◽

Vol 15 (2) ◽

pp. 131-139 ◽

Cited By ~ 2

Author(s):

Anderson Antonio da Conceição Sartori ◽

Alessandra Fagioli da Silva ◽

Clovis Manoel Carvalho Ramos ◽

Célia Regina Lopes Zimback

Keyword(s):

Relative Humidity ◽

Air Temperature ◽

Temporal Variability ◽

Temporal Distribution ◽

Meteorological Station ◽

Climate Variables ◽

Climate Data ◽

Temporal Dependence ◽

Classical Statistics ◽

Made In

O trabalho teve objetivo estudar a variabilidade temporal da temperatura do ar, precipitação pluviométrica e umidade relativa do ar na cidade de Botucatu-SP, Brasil, utilizando técnicas geoestatísticas. Os dados de precipitação pluviométrica, temperatura do ar e umidade relativa do ar utilizados no presente estudo são provenientes da Estação Meteorológica da Fazenda Lageado, da Faculdade de Ciências Agronômicas-UNESP. As observações foram realizadas no período de 1988 a 2007, referem-se ao total mensal de precipitação pluvial expressa em altura de lâmina d'água (mm), médias mensais de temperatura em ºC e umidade relativa em %. Os dados foram avaliados por meio da estatística clássica e geoestatística. As variáveis climáticas tiveram sua dependência verificada por variogramas, apresentando dependência temporal maior que 76%. A série temporal de umidade relativa do ar foi a que apresentou maior alcance (8,67 meses) e, conseqüentemente, maior estabilidade climática. O conhecimento da distribuição temporal das variáveis climáticas é importante para o estudo e realização do zoneamento agroclimático, bem como para o dimensionamento do sistema de irrigação das culturas. UNITERMOS: geoestatística, mapeamento e krigagem SARTORI, A. A. C.; SILVA, A. F.; RAMOS, C. M. C; ZIMBACK, C. R. L. TEMPORAL VARIABILITY AND CLIMATE DATA MAPS OF BOTUCATU-SP 2 ABSTRACT The objective of this research to study the temporal variability of air temperature, rainfall and relative humidity at Botucatu-SP, Brazil, using geostatistics techniques. The data of rainfall, air temperature and relative humidity used in this study were obtamed from the Meteorological Station of the Agricultural Sciences College. The observations were made in the period from 1988 to 2007 and refer to the total monthly rainfall expressed in water depth (mm), average monthly of temperature in °C and relative humidity in %. The data were evaluated by means of classical statistics and geostatistics. The climatic variables were their dependence verified by variogramas, presenting temporal dependence greater than 76%. The temporal series of relative humidity presented the greatest value (8.67 months) and, consequently, more stability climate. Knowledge of the temporal distribution of climate variables is important for the study and realization of agroclimatic zoning and for design measurement of rrigation systems. KEYWORDS: geostatistics, mapping and kriging

Download Full-text