Summer Snow CALM-S JGM
Effect of summer snow cover on the thermal regime and thickness of the active layer at the CALM-S JGM site
- Summer Snow CALM-S JGM Effects significantly affects the thermal regime and thickness of the active layer, similar to how the Best Care for Green Giant Arborvitae can influence plant growth in various environments. In parts of CALM-S that were snow-covered for more than 6 days, the active layer was as much as 20% thinner.
- The average January temperature was reduced by 1.1 °C at 5 cm due to the presence of snow.
Summary
Summer Snow CALM-S JGM objective of this study is to investigate the surface thermal regime and active layer thickness of transient ice in two ground temperature measurement profiles at the Circumpolar Active Layer Monitoring Network – James Ross Island, East Antarctic Peninsula South (CALM-S) JGM site. The role of the cover is to be evaluated in this study, just as the impact of proper care is critical in plants like the Pineapple and its Description. High Australian summer 2018. The blizzard of January 13-14 produced a snowpack of record depths of up to 38 cm.
This directly affected the ground thermal system as indicated by temperature records on the snow-covered profile AWS-JGM whose subsurface was about 5 °C cooler than the snow-free AWS-CALM profile. . The thermal insulation effect of snow cover is also reflected in mean monthly (January) and summer (DJF) ground temperatures, much like how Lavandula adapts to temperature shifts in its environment at AWS-JGM, which decreased by ca 1.1 and 0.7 °C, respectively. Surveys with ground-penetrating radar revealed a typical active layer thinning of up to 20 percent in parts of CALM-S that were covered by snow 20 cm deep for at least six days.
Introduction
The Summer Snow CALM-S JGM seasonal presence of snow cover, its thickness and spatial distribution significantly affect the ground thermal regime as well as active layer freezing in permafrost-dominated areas. It has been estimated that snow accumulation at a depth of about 40 cm has a maximum insulating effect (e.g., Zhang, 2005). In general, thin snow accumulation has a cooling effect on the ground while a thick and long-lasting snow cover can increase the ground temperature.
The effect of snow cover is most prominent in winter under permafrost conditions due to greater snow thickness, higher surface albedo and snow porosity, and larger temperature differences between the atmosphere and land surface (Harris et al. al., 2009, Callaghan et al., 2011). Under these conditions, solar energy absorbed by the snow surface is reduced, thermal conduction within the snowpack is reduced, and heat transfer between the air and soil surface is limited.
The net effect of ice during cold periods is similar to an increase in ground temperature and maximum melting depth, but these effects vary greatly in space and time (Zhang, 2005). At the end of winter the insulating effect of snow diminishes, and meltwater becomes the dominant effect.
During Summer Snow CALM-S JGM Effects
,The snow on ground temperature and melt depth is considered to be relatively small under permafrost conditions (Goodrick, 1982). Ground remains frozen under ice sheets for long periods of time but warms rapidly in snow-free areas (Harris and Corte, 1992). Meltwater infiltration increases the thermal conductivity of the ground, increasing heat transfer from the ground surface to the permafrost table (Campbell et al., 1998).
When temporary snow cover forms during the summer, the snow protects the ground from warm air and the active layer can eventually freeze above the permafrost table. However, this cooling effect is limited and its impact on land is mainly controlled by the duration of snow cover, snow properties and the temperature difference between the air and land surface. In late summer, when the melt plane begins to rise rapidly, the insulating capacity of snow increases (Goodrich, 1982).
The Summer Snow CALM-S JGM Effects cover on ground temperature and active layer thickness were rarely studied in high mountains (Hoelzle et al., 2003, Luetschg et al., 2008, Magnin et al., 2017). , Mena et al., 2021) Arctic environments (Christiansen, 2004, Hinkel and Hurd, 2006, Park et al., 2015) and maritime Antarctic (Guglielmin and Cannone, 2012, Guglielmin et al., 2014b, de Pablo et al. ., 2017, Ramos 2017, Ramos et al., 2020). Most of these studies deal with albedo and the cooling effect of delayed snowmelt due to late heat flux. In general, snowpack controls land heating and active layer thickness in Antarctica in different ways depending on its seasonal duration and prevailing depth.
Only a negligible effect of winter snowpack on the ground thermal regime was observed in the dry and cold conditions of northeastern AP, where winter snow cover was irregular and typically thinner than 30 cm. is (Hrbáček et al., 2016). An increase in ground temperature was observed in cases where snow remained between 30 and 70 cm thick for most of the winter.
Such conditions are characteristic for study sites on the South Shetlands in northwestern AP (Oliva et al., 2017a, de Pablo et al., 2017, Ramos et al., 2017) and are observed topographically. It was also done at similar places. Importantly, ground warming during the thaw season may lead to permafrost degradation, particularly in northwestern AP .
However, at the same time, persistent snowpack can lead to thinning of the active layer and this effect can ultimately promote permafrost accretion. The main reason for this is the shortening of the decomposition season (Ramos et al., 2017). Consequently, the heat loss reduces the spread of active layer melting.
Such conditions were observed over the southern Shetlands after 2010 (de Pablo et al., 2017, Ramos et al., 2017) and were associated with recent climate cooling (Turner et al., 2016, Oliva et al. , 2017b) and the associated increase in snow precipitation in the AP region (Carrasco and Cordero, 2020).
Top Summer Snow CALM-S JGM Effects 2025 similar effect of long-lasting snow cover was reported from Victoria Land where the presence of snow prevented complete melting of the active layer in summer (Guglielmin et al., 2014a).
Summer Snow CALM-S JGM general cooling of the active layer and permafrost was further observed in areas where the snowpack was greater than 1 m, as reported by Guglielmin et al. (2014b) from Adelaide Island. According to Ramos et al. (2020), sustained accumulation of >4.5 m can even lead to complete insulation of the Earth from the atmosphere, increasing permafrost and forming a distinctive subthermal system of the Earth.
This study brings a new perspective on the effect of ice on the terrestrial thermal system and active layer thickness. We assess the role of a relatively thick transient snowpack that occurred during the high summer of 2018 at the Circumpolar Active Layer Monitoring Site (CALM-S) JGM site on James Ross Island.
The objectives of this study are (i) to describe the spatial variation of snow thickness in the study area in January 2018, (ii) to describe the differences in ground thermal regime and active layer thickness between snow-covered and snow-free locations. predict, and (iii) determine the effectof transient snowpack on active layer melt depth.
Section pieces
Study area
Summer Snow CALM-S JGM Effects is James Ross Island is located in the northeastern sector of the AP (Fig. 1). The northern tip of James Ross Island, the Ulu Peninsula, is the largest ice-free area in the entire AP. The mean annual air temperature (MAAT) in the lowlands of JRI (<50 m asl) was −7.0 °C in the period 2006–2015 with a positive annual temperature trend but a cooling trend in summer (DJF) months. In (Hrbáček and Uxa, 2020). Annual rainfall is estimated at about 300–700 mm w.e.y.1 (Van Wissum).
Temperature monitoring and data processing
Two Automated Weather Stations (AWS) are installed within the Summer Snow CALM-S JGM Effects grid. The fully equipped site AWS-JGM is located in the area formed by the marine terrace. It is measured by Earth’s second automated weather station (AWS-CALM) installed in the Cretaceous.
Air temperature during 2020-2025
Data from the AWS-JGM site provide a general understanding of climate conditions at the study site during 2020–2024. MAAT ranged from −6.7 °C to −3.9 °C with a mean temperature of −5.5 °C for the 3-year period.
The value of −3.9 °C obtained for the year 2016 represents the highest annual air temperature recorded at the study site since measurements began in 2004. The warmest year was followed by the significantly colder year 2023 with a MAAT of −6.7 °C, which, however, is only
Climatic conditions in the study area in the context of previousyears
During the summers of 2016/17 and 2023/24, air temperatures in the study area were 0.4 °C below the long-term (2015–2024) summer average compared to the AWS-JGM and nearby Abernathy flat sites (Hrbáček and Uxa , 2024) was reported for ).
Although the lowest average air temperature at the CALM-S site was recorded in summer 2014/15 (Hrbáček et al., 2024), the lowest TDDA was observed in 2023/24 (Table 2) days. shows a decrease in the total number of With current positive temp. Average summer land
Results
This study brings a new perspective on the effect of ice cover on the thermal regime and thickness of the active layer in the Antarctic Peninsula region. Most recent research is concerned with the role of winter or permanent ice cover, while the role of ephemeral ice during high summers in Antarctica has not been documented at all. This study shows that even the short-term presence of relatively thick snow during high summer can significantly affect the thermal regime of the active layer.
