An automated version of the Lamb weather type classification scheme was used to study the relationship between atmospheric circulation patterns and rainfall in the northwestern part of the Iberian Peninsula, which is an important area of crossing influences of the different teleconnection patterns of the Northern Hemisphere. We calculated the correlation between the most important teleconnection patterns that affect this area and the different types of weather circulation. In this area, anticyclone weather types are the most frequent in any part of the year. The frequency of occurrence of W and SW situations is also significant in autumn and winter. The correlation between weather types (WT) and teleconnection patterns showed that the North Atlantic Oscillation (NAO) index has significant correlations only in winter, while other patterns, such as the Eastern Atlantic (EA), have significant correlations in the other seasons. As a result of these correlations, the EA is a more relevant pattern than the NAO for describing the Galician climate throughout the year. We also calculated correlations between the North Hemisphere Annular Mode (NAM) and the different types of weather types. The NAM shows significant correlations throughout the year. Hence, the NAM is more relevant than the NAO, which is its local manifestation. Copyright © 2007 Royal Meteorological Society

In the current climate change scenario, heat waves have become one of the most concerning extreme climatic events, both because of their implications for human health and the economy, and because of their increase in intensity and frequency in recent decades. This work presents for the first time a climatological analysis of heat waves in the Iberian Peninsula and Balearic Archipelago (IPB) using the Excess Heat Factor index (EHF). This index considers the factor of intensity and the acclimatization process of human body in the study of heat waves. We focused on the intensity (also called severity), duration, frequency and spatial extension of heat waves in the IPB in the 1950-2020 period. The exceptional heat wave of August 2018 was approached in a similar way to further explore the usefulness of the EHF index. We found that the EHF index identified heat wave conditions 2 days earlier than indices that used only maximum temperatures. Results showed a significant increase in intensity, duration, frequency and spatial extension of heat waves for the whole IPB for 1950-2020 period. The average extent of heat waves increased by 4.0% per decade and the maximum extent by 4.1% per decade. This trend suggested a significant increase in human exposure, droughts, fire risk and energy demand in this region in the last decades.

Viticultural climatic indices were assessed for the evaluation of the meteorological variations in the requirements of wine cultivars. The applied bioclimatic indices have been widely used to provide an initial evaluation of climate change impacts on grapevine and to delineate wine regions and suitable areas for planting around the world. The study was carried out over a period of 16 years (from 2000 to 2015) in five Designation of Origin areas in Northwestern Spain located in the Eurosiberian region, the transition zone between the Eurosiberian and the Mediterranean areas, and in the Mediterranean area. In addition, the high-resolution meteorological dataset “Spain02” was applied to the bioclimatic indices for the period 1950–2095. To further assess the performance of “Spain02”, Taylor diagrams were elaborated for the different bioclimatic indices. A significant trend to an increase of the Winkler, Huglin, Night Cold Index and GSS Indices was detected in the North-western Spain, whereas slight negative trends for BBLI and GSP Indices were observed. To analyze future projections 2061–2095, data from the high-resolution dynamically downscaled daily climate simulations from EURO-CORDEX project were used. To further assess the performance of Spain02, Taylor diagrams were elaborated for the different bioclimatic indices. A trend to an increase of the Winkler, Huglin, Night Cold Index and GSP Indices was detected in Northwestern Spain, whereas slight negative trends for BBLI and GSP Indices were observed. Our results showed that climatic conditions in the study region could variate for the crop in the future, more for Mediterranean than Eurosiberian bioclimatic area. Due to an advance in the phenological events or the vintage data, more alcohol-fortified wines and variations in the acidity level of wines could be expected in Northwestern Spain, these processes being most noticeable in the Mediterranean area. The projections for the BBLI and GSP Indices will induce a decrease in the pressure of the mildew attacks incidence in the areas located at the Eurosiberian region and the nearest transition zones. Projections showed if the trend of temperature increase continues, some cultural practice variations should be conducted in order to preserve the grape cultivation suitability in the studied area.

Alvarez, I., Lorenzo, M. N., and deCastro, M. 2012. Analysis of chlorophyll a concentration along the Galician coast: seasonal variability and trends. – ICES Journal of Marine Science, 69: 728–738.