Relationships between permafrost distribution and surface organic layers near Esso, central Kamchatka, Russian Far East

Abstract

Unique boreal forest, consisting mainly of sparse larch (Larix cajanderii), creeping pine (Pinus pumila) and birch forest (Betula ermanii), occurs above the lower elevational limit of discontinuous permafrost of about 500 m above sea level in the area around Esso, central Kamchatka ($568N). Permafrost is present beneath surfaces covered by Sphagnum or creeping pine, but is absent beneath birch forest. Thermal conductivities in mid-September are low in Sphagnum (0.07-0.19 W/(mÁK)) and in the thick (13-20 cm) litter layer beneath creeping pine-covered areas (0.06-0.09 W/(mÁK)). Seasonal changes in the subsurface ground temperatures beneath creeping pine show that the surface litter prevents ground temperature increases at depth in summer, resulting in a thin active layer (several decimetres). The surface organic layer appears to be the most important factor controlling the presence or absence of permafrost in this area.

Advancement toward coupling of the VAMPER permafrost model within the Earth system model <I>i</I>LOVECLIM (version 1.0): description and validation

“…Indeed, there a number of other (sub)surface processes not included in the current ECBilt-VAMPERS coupling which may reduce the apparent cold bias. These effects alter the seasonal behavior of the thermal diffusivity in the subsurface and have been well-documented in observational studies (Williams and Burn, 1996;Woo and Xia, 1996;Fukui et al, 2008). Smith and Riseborough (2002) simplified these mechanisms into the surface offset (air to ground surface) and the thermal offset (ground surface to top of the permafrost).…”

“…Such factors as vegetation and the organic layer, which can vary due to local topography and micro-climatic conditions, have been shown to affect the ac- tive layer and ground thermal regime (Shur and Jorgenson, 2007;Fukui et al, 2008;Lewkowicz et al, 2011;Wang et al, 2014). Consequently, given a specific borehole site, some discrepancy in the permafrost thickness estimate will likely occur between our simplified interpretation and that which results from including more complex and local interactions.…”

Soil temperature response to 21st century global warming: the role of and some implications for peat carbon in thawing permafrost soils in North America

“…Currently, relict permafrost formed during the Little Ice Age is found in isolated patches within Canadian bogs despite warmer air temperatures (Halsey et al, 1995;Vitt et al, 1994). Additionally, peat depth is an important control on the active layer depth (Fukui et al, 2008;Yi et al, 2006). It is therefore imperative to consider the spatial distribution of those properties in attempts to model the future distribution of permafrost areas and the role of peatlands in the global climate system.…”

Boreal Forests of Kamchatka: Structure and Composition

“…The forest altitudinal limit is around 800 m [24]. In Esso valley permafrost is sporadic and discontinuous with a lower limit between 400-900 m above sea level (asl) [26]. Climatic data (1940-1995) suggest a mean annual temperature (MAT) of −3.1 °C, ranging from a minimum monthly mean in January of −18.7 °C to a maximum in July of 13.2 °C.…”

“…P. pumila is likely to have a pronounced effect on seedling regeneration patterns and through insulation of the soil will maintain permafrost and prevent thawing to below 40 cm depth [26]. In other forests, the woody sub-canopy may influence spatial patterns of regeneration, for example Rhododendron hodgsonii Hook.…”