Dune movement and climatic changes on the north-eastern Tibetan Plateau – Gonghe Basin and neighboring regions

Autor(en)

Lukas Dörwald, Frank Lehmkuhl, Janek Walk, Lucie Delobel, Bruno Boemke, Andreas Baas, Deguo Zhang, Xiaoping Yang, Georg Stauch

Abstrakt

The movement of active dunes is tightly linked to climatic conditions (e.g. wind regime, temperature, and precipitation) as well as human influence (e.g. grazing, dune fixation, infrastructure, and greening activities). Dune migration rates can be studied to draw conclusions of changing wind conditions over time. The intramontane Gonghe Basin, the source region of the Yellow River (Huang He), as well as other neighbouring regions upon the northern Tibetan Plateau are all influenced by two major wind regimes: the mid-latitude Westerlies and the Asian summer monsoon. To investigate environmental changes, we combined optical remote sensing techniques with climatic datasets. High resolution satellite images of the last six decades, such as Corona KH-4B, are used to map dunes and calculate their respective migration rates and allow a remote sensing approach as far back as 1968. Climatic changes from the ERA-5 reanalysis dataset and NDVI values were processed alongside, using Google Earth Engine. Relating the dunes’ surface processes to climate model data shows an accordance between slowing migration, expanding vegetation and a decrease in Sand Drift Potential, calculated from ERA-5 data, recently updated to the 1950s. Within the Gonghe Basin, 76 dunes are studied over multiple time sections; in the source region of the yellow river, more than 400 were mapped for comparison. The study areas differ in topography, vegetation, agricultural use, infrastructure, and fluvial influences. This offers a good testing ground for the aforementioned assumptions.

Organisation(en)

Institut für Geographie und Regionalforschung

Externe Organisation(en)

Rheinisch-Westfälische Technische Hochschule Aachen, King's College London, Zhejiang University (ZJU)

Publikationsdatum

2023

ÖFOS 2012

207402 Fernerkundung, 105404 Geomorphologie

Sustainable Development Goals

SDG 13 – Maßnahmen zum Klimaschutz

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/743280d9-0929-42fe-b630-10ba82fb390c