Subpixel heterogeneity of ice-wedge polygonal tundra:  a multi-scale analysis of land cover and evapotranspiration in the Lena River Delta, Siberia

Abstract. Samoylov Island is centrally located within the Lena River Delta at 72° N, 126° E and lies within the Siberian zone of continuous permafrost. The landscape on Samoylov Island consists mainly of late Holocene river terraces with polygonal tundra, ponds and lakes, and an active floodplain. The island has been the focus of numerous multidisciplinary studies since 1993, which have focused on climate, land cover, ecology, hydrology, permafrost and limnology. This paper aims to provide a framework for future studies by describing the characteristics of the island's meteorological parameters (temperature, radiation and snow cover), soil temperature, and soil moisture. The land surface characteristics have been described using high resolution aerial images in combination with data from ground-based observations. Of note is that deeper permafrost temperatures have increased between 0.3 to 1.3 °C over the last five years. However, no clear warming of air and active layer temperatures is detected since 1998, though winter air temperatures during recent years have not been as cold as in earlier years. Data related to this article are archived under: http://doi. pangaea.de/10.1594/PANGAEA.806233 .

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Sensitivity of pond methane emissions in the Lena River Delta to climate changes in new model MeEP

10.5194/egusphere-egu21-8387 ◽

2021 ◽

Author(s):

Zoé Rehder ◽

Thomas Kleinen ◽

Lars Kutzbach ◽

Victor Stepanenko ◽

Victor Brovkin

Keyword(s):

Spatial Variability ◽

Model Performance ◽

Methane Emissions ◽

River Delta ◽

Lena River ◽

Methane Fluxes ◽

Eddy Covariance Measurements ◽

Ice Wedge ◽

Set Up ◽

Lena River Delta

<p>Permafrost ponds are a steady source of methane. However, it is difficult to assess the sensitivity of pond methane emissions to ongoing warming and climate-change-induced drainage, because pond methane emissions show large temporal and spatial variability already on local scale.<br>We study this sensitivity on the landscape level with a new process-based model for Methane Emissions from Ponds (MeEP model), which simulates the three main pathways of methane emissions (diffusion, plant-mediated transport and ebullition) as well as the temperature profile of the water column and the surrounding soils. The model was set up for the polygonal tundra in the Lena River Delta. Due to a temporal resolution of one hour, it is capable of capturing the diurnal, day-to-day and seasonal variability in methane fluxes. MeEP also considers one of the main drivers of spatial variability - ground heterogeneity. Depending on where ponds form in the polygonal tundra, they can be classified as ice-wedge, polygonal-centre or merged-polygonal ponds. In MeEP, each of these pond types is simulated separately and the representation of these ponds was informed by dedicated measurements.<br>The model performance is validated against eddy-covariance measurements of methane fluxes and against in-situ measurements of the aqueous methane concentration, both obtained on Samoylov Island.&#160; We will present results regarding the sensitivity of modeled methane emissions from ponds to warming and drainage on the landscape scale.</p>

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Multi-scale analysis of hydrological connectivity and plant response in the Yellow River Delta

The Science of The Total Environment ◽

10.1016/j.scitotenv.2019.134889 ◽

2020 ◽

Vol 702 ◽

pp. 134889 ◽

Cited By ~ 5

Author(s):

Jiakai Liu ◽

Bernard A. Engel ◽

Yu Wang ◽

Guifang Zhang ◽

Zhenming Zhang ◽

...

Keyword(s):

Yellow River ◽

Yellow River Delta ◽

Plant Response ◽

River Delta ◽

The Yellow River ◽

Hydrological Connectivity ◽

Scale Analysis ◽

The Yellow River Delta ◽

Multi Scale ◽

Multi Scale Analysis

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Baseline characteristics of climate, permafrost, and land cover from a new permafrost observatory in the Lena River Delta, Siberia (1998−2011)

Biogeosciences Discussions ◽

10.5194/bgd-9-13627-2012 ◽

2012 ◽

Vol 9 (10) ◽

pp. 13627-13684 ◽

Cited By ~ 11

Author(s):

J. Boike ◽

B. Kattenstroth ◽

K. Abramova ◽

N. Bornemann ◽

A. Chetverova ◽

...

Keyword(s):

Land Cover ◽

Land Surface ◽

Surface Characteristics ◽

River Delta ◽

Aerial Images ◽

Lena River ◽

River Terraces ◽

Air Temperatures ◽

Tundra Ponds ◽

Lena River Delta

Abstract. Samoylov Island is centrally located within the Lena River Delta at 72° N, 126° E and lies within the Siberian zone of continuous permafrost. The landscape on Samoylov Island consists mainly of late Holocene river terraces with polygonal tundra, ponds and lakes, and an active floodplain. The island has been the focus of numerous multidisciplinary studies since 1993, which have focused on climate, land cover, ecology, hydrology, permafrost, and limnology. This paper aims to provide a framework for future studies by describing the characteristics of the island's meteorological parameters (temperature, radiation, and snow cover), soil temperature, and soil moisture. The land surface characteristics have been described using high resolution aerial images in combination with data from ground-based observations. Of note is that deeper permafrost temperatures have increased between 0.5 to 1 °C over the last five years. However, no clear warming of air and active layer temperatures is detected since 1998, though winter air temperatures during recent years have not been as cold as in earlier years.

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