Understanding the spring phenology of Arctic tundra using multiple satellite data products and ground observations
- PDF / 723,532 Bytes
- 14 Pages / 595.276 x 793.701 pts Page_size
- 107 Downloads / 182 Views
derstanding the spring phenology of Arctic tundra using multiple satellite data products and ground observations 1,2
1
1*
3
Jiangshan ZHENG , Xiyan XU , Gensuo JIA & Wenjin WU 1
CAS Key Laboratory of Regional Climate-Environment for Temperate East Asia, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China; University of Chinese Academy of Sciences, Beijing 100049, China; Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing 100094, China 2
3
Received September 28, 2019; revised May 8, 2020; accepted June 9, 2020; published online August 5, 2020
Abstract The Arctic is highly sensitive to climate change, and the rise in its near-surface air temperatures has been almost twice the global average. The increased growth of the Arctic tundra and its changing seasonality have been observed, largely in response to the impacts of climate change. In this study, we investigated the temporal and spatial variations of the start of the growing season (SOS) using various remote sensing indices, including Normalized Difference Vegetation Index, Normalized Difference Water Index, and Normalized Difference Snow Index from 2000 to 2018 in Arctic tundra regions. The SOS was derived at 29 sites from ground observations, including CO2 flux data, phenological images, and field records that were used to validate the SOS from remote sensing indices. Our results revealed that the SOS was delayed by approximately 3.86 days per degree of latitude along the northward latitudinal gradient. From 2000 to 2018, the start of the growing season and the interannual variability differed greatly among tundra types. Although the overall trends were not significant from 2000 to 2018, the start of the growing season in different plant communities was consistently delayed after 2016. High Arctic vegetation, including (1) low wetland complexes (5–10 cm) dominated by sedges, grasses, and mosses, and (2) slightly higher prostrate and hemi-prostrate shrubs (< 15 cm), experienced a delayed start of the growing season. The start of the growing season of Low Arctic vegetation, comprising (1) wetland complexes (10–40 cm) dominated by sedges, grasses, mosses, and dwarf shrubs, (2) moist tundra (20–50 cm) dominated by tussock cottongrass and dwarf shrubs, and (3) transition zones containing tundra and taiga, displayed no obvious trend. Keywords Citation:
Arctic, Phenology, Leaf-out, Tundra, Remote sensing, Climate
Zheng J, Xu X, Jia G, Wu W. 2020. Understanding the spring phenology of Arctic tundra using multiple satellite data products and ground observations. Science China Earth Sciences, 63, https://doi.org/10.1007/s11430-019-9644-8
1. Introduction Over the past century, the Earth’s climate has been undergoing significant changes characterized by a continued warming trend, with stronger warming at higher latitudes. In recent decades, the “Arctic amplification” effect due to the reduction of sea ice has intensified (Dai et al., 2019). The Arctic near-surface air temperatures have risen at nearly * Cor
Data Loading...
