[1] The North Atlantic Oscillation (NAO) is one of the most prominent patterns of atmospheric circulation variability over the Northern hemisphere, yet little is known about its underlying mechanism of phase conversion. Our analysis reveals that the recent decline of Aerosol Optical Depth (AOD) over the Subtropical Atlantic Ocean (SAO) contributes significantly to the enhancement of SAO Sea Sur...

[1] Influence of winter pre-conditioning of Arctic sea ice due to atmospheric forcing associated with the North Atlantic Oscillation (NAO) on the reduction in summer sea ice extent is studied. It is found that winter sea ice is about 50 cm thinner in high-NAO index years than in low-NAO index years in the Eurasian coastal region mainly due to stronger wind-driven ice export. The thinner wintert...

[1] A study of the influences of interdecadal and interannual oceanic-atmospheric influences on April 1 Snow-Water Equivalent (SWE) in the western U.S. is presented. SWE data was identified at 323 Natural Resources Conservation Service (NRCS) SNOTEL (SNOwpack TELemetrysites) stations for the period of 1961 to 2004 and for 121 SNOTEL stations for the period 1941 to 2004. The phases (cold/negativ...

Projections of the winter North Atlantic circulation exhibit large spread. Coupled Model Intercomparison Project archives typically provide only a few ensemble members per model, rendering it difficult to quantify reducible model structural uncertainty and irreducible internal variability (IV) in projections. We estimate using Multimodel Large Ensemble Archive that differences explain two-third...

We evaluated evidence of an effect of climate on the numerical response of a coyote (Canis latrans) population to their keystone prey, snowshoe hares (Lepus americanus), in a Canadian boreal forest. Six a priori hypotheses of the coyote numerical response were developed that postulated linear, nonlinear, additive, and interactive effects of prey and climate. Model selection procedures showed th...

Recent studies have shown that the population dynamics of deep-sea organisms are affected by coupling between surface oceanic processes and energy, or trophic resources, reaching the sea floor. I analysed the correlation between the landings of a deep-sea shrimp (Aristeus antennatus) in Catalonia (NW Mediterranean) and the climatic indices of the annual North Atlantic Oscillation (NAO) and wint...

[1] The winter dO signal is extracted from 7 Greenland ice cores covering the past 700 years. To filter out noise and local variations in the 7 isotope records a principal component analysis is carried out on the ice core data. A comparison between the time series of the first principal component (PC1) with 67 years of winter (December to March) temperature measurements from 3 southern Greenlan...

Recent winter warming over Central Europe associated with a positive phase of the North Atlantic Oscillation (NAO) strongly influenced the thermal and water column stability properties of deep Lake Constance (zmean 5 101 m). Volumetrically weighted average water temperatures have increased since the 1960s by an average of 0.0178C yr21, and its interannual variability was strongly related to the...

Recent winter warming over Central Europe associated with a positive phase of the North Atlantic Oscillation (NAO) strongly influenced the thermal and water column stability properties of deep Lake Constance (zmean 5 101 m). Volumetrically weighted average water temperatures have increased since the 1960s by an average of 0.0178C yr21, and its interannual variability was strongly related to the...

— Evidence is reviewed for climate change and its causes over the interval spanning roughly the past millennium. Particular emphasis is placed on patterns of climate change influencing Mediterranean climates of the Northern Hemisphere. The evidence is taken from studies using high-resolution climate “proxy” data sources, and climate modeling simulations. The available evidence suggests that for...