Coherent Interannual Variations of Springtime Surface Temperature and Temperature Extremes Between Central‐Northern Europe and Northeast Asia

Abstract

This study reveals a strong coherent interannual variation in spring surface air temperature (SAT) and temperature extremes between central‐northern Europe (45–70°N, 0–30°E) and Northeast Asia (40–70°N, 110–140°E). The regional mean spring SAT over the two regions is highly correlated, with a correlation of 0.6 during 1950–2017. Arctic Oscillation (AO) and an atmospheric teleconnection, termed the North Atlantic‐Eurasian (NAE) pattern, both play important roles in connecting SAT anomalies over the two regions. Anticyclonic anomalies are seen over central‐northern Europe and Northeast Asia during positive phases of the spring AO and NAE teleconnections. The associated southerly and westerly wind anomalies to the northwestern side of the anomalous anticyclones lead to surface warming over the two regions via anomalous wind‐induced heat advection from lower latitudes. In addition, a decrease in cloud cover and an accompanying increase in surface downward shortwave radiation also contribute to the coherent SAT warming over central‐northern Europe and Northeast Asia. We suggest that synoptic‐scale eddies forcings are crucial to the maintenance of the spring NAE teleconnection. Atmospheric model experiments indicate that the North Atlantic sea surface temperature anomalies also partly contribute to the maintenance of the NAE‐related atmospheric anomalies over the North Atlantic and European regions. The observed coherent spring SAT variations over central‐northern Europe and Northeast Asia and their associations with the AO and midlatitude atmospheric teleconnections can be reproduced in the long historical simulation of a coupled model. This study has implication for the understanding of concurrent occurrence of extreme temperature events over different regions of Eurasia.

The Dominant Modes of Spring Land Surface Temperature Over Western Eurasia and Their Possible Linkages With Large‐Scale Atmospheric Teleconnection Patterns

“…The observational temperature data used in this study are monthly mean near‐surface temperature from the Climatic Research Unit (CRU) T.S 4.03 data set (Harris et al., 2020) with a horizontal resolution of 0.5° × 0.5°, available from 1901 to 2018. The CRU TS gridded data set provides monthly meteorological parameters for global land areas and is widely used to study Eurasian surface temperature variability (e.g., Chen, Wu, Chen, Yao et al., 2020; Li et al., 2021; Sun, 2017). For convenience, the temperature data obtained from CRU are referred to as “observations” in this study.…”

“…Figure 1c). In addition, the atmospheric circulation pattern above resembles a spring teleconnection pattern over the North Atlantic and mid‐high latitude Eurasia, termed the North Atlantic‐Eurasian teleconnection pattern, which has significant impacts on Eurasian spring surface temperature (Chen, Wu, Chen, Hu, et al., 2020, Chen, Wu, Chen, Yao, et al., 2020). The EOF3‐related LST anomalies in our study also agree well with their results.…”

The possible impact of solar activity on the summer temperature distribution over Eurasia

“…Kilcik et al (2010) proved that the response of Atlantic-Eurasian regions depends on the latitudes and solar activity affects the temperature of mid-latitudes significantly in winter. Moreover, some scientists proposed that solar forcing has a significant effect on the wintertime temperature and precipitation over Asia (Kossobokov et al, 2010;Chen et al, 2015;Ojala et al, 2015;Song et al, 2019;Chen et al, 2020;Xu et al, 2020). Recently, Xu et al (2020) revealed that extreme cold events are highly related to the energetic particle precipitation in winter over Eurasia and the interaction of wave-mean flow in the stratosphere and troposphere is an important medium in the downward process of solar signals.…”