Permafrost Degradation Induces the Abrupt Changes of Vegetation NDVI in the Northern Hemisphere.

Autor: Yang, Yanpeng, Wang, Xufeng, Wang, Tonghong
Předmět:
Zdroj: Earth's Future; Oct2024, Vol. 12 Issue 10, p1-21, 21p
Abstrakt: Permafrost, widely distributed in the Northern Hemisphere, plays a vital role in regulating heat and moisture cycles within ecosystems. In the last four decades, due to global warming, permafrost degradation has accelerated significantly in high latitudes and altitudes. However, the impact of permafrost degradation on vegetation remains poorly understood to date. Based on active layer thickness (ALT) monitoring data, meteorological data and normalized difference vegetation index (NDVI) data, we found that most ALT‐monitored sites in the Northern Hemisphere show an increasing trend in NDVI and ALT. This suggests an overall increase in NDVI from 1980 to 2021 while permafrost degradation has been occurring. Permafrost degradation positively influences NDVI growth, with the intensity of the effects varying across land cover types and permafrost regions. Furthermore, based on Mann‐Kendall trend test, we detected abrupt changes in NDVI and environmental factors, further confirming that there is a strong consistency between the abrupt changes of ALT and NDVI, and the consistency between the abrupt change events of ALT and NDVI is stronger than that of air temperature and precipitation. These findings work toward a better comprehending of permafrost effects on vegetation growth in the context of climate change. Plain Language Summary: Our research focuses on the influence of permafrost degradation on vegetation in high‐latitude and high‐altitude regions of the Northern Hemisphere. By analyzing permafrost monitoring and vegetation data, we have observed a widespread occurrence of permafrost degradation and vegetation greening in recent years across the Northern Hemisphere. Our analysis has revealed a strong connection between permafrost degradation and vegetation greening in permafrost areas, and the impact varies with different vegetation and permafrost types. In addition, we further investigated the consistency of abrupt changes in the vegetation growth with various environmental factors. It can be seen that despite the significant influence of air temperature changes on vegetation growth in permafrost regions of the Northern Hemisphere, the abrupt change of vegetation growth is consistent with the abrupt change in the process of permafrost degradation, indicating that vegetation growth displays a heightened sensitivity to permafrost degradation. These findings provide valuable insights into the ecological consequences of permafrost changes in high‐latitude and high‐altitude areas under the influence of climate change. Key Points: Vegetation in the Northern Hemisphere shows a greening trend, and permafrost shows a degradation trendPermafrost degradation positively influences vegetation growth, with the intensity of the effects varying by vegetation and permafrost typesAbrupt changes in vegetation growth are more consistent with abrupt permafrost degradation than with meteorological factors [ABSTRACT FROM AUTHOR]
Databáze: Complementary Index