资源环境科技发展态势分析平台

The rapid loss of Arctic sea-ice could cause climate changes in the Northern Hemisphere, especially in the middle and high latitudes. In this study, the interannual linkage between winter (December-January-February) sea-ice cover over the Barents Sea (SICBS) and spring (April-May-June) vegetation greenness over Eurasia, as well as the possible mechanisms of this teleconnection are investigated. The Normalized Difference Vegetation Index (NDVI) derived from the advanced very high resolution radiometer is used as the proxy of vegetation greenness. During 1982-2015, the winter SICBS is significantly correlated with the spring NDVI over Eurasia (NDVIEA). The positive (negative) winter SICBS anomalies tend to increase (decrease) the spring NDVIEA. The results show that the increased winter SICBS corresponds to higher winter surface air temperature and soil temperature over most parts of Eurasia, and in turn, corresponds to less winter snow cover and less snow water equivalent. The persistent less and thinner snow cover from winter to spring over Eurasia, especially over Western and Central Siberia, tends to induce increased surface air temperature through decreased surface albedo and less snowmelt latent heat. Subsequently, the increased surface air temperature corresponding to increased SICBS contributes to higher vegetation greenness over Eurasia in spring and vice versa. The ensemble simulations from the Community Atmosphere Model version 5 further confirm the associated possible physical mechanism. Meanwhile, the variability of the SICBS shows good seasonal persistence from winter to spring. The increased spring SICBS also leads to the changes in climate conditions that are favorable for increased NDVI near Lake Baikal.