O Atlas do Ambiente, que há mais de 30 anos vem sendo publicado em papel, teve como objetivo disponibilizar ao público um conjunto de informação geográfica de cariz eminentemente ambiental. O processo de implementação de um Sistema de Informação Geográfica (SIG) tendo como base a informação desse Atlas, foi iniciado em 1987. Atualmente, a versão digital do Atlas do Ambiente integra-se num projeto que pretende ir ao encontro das exigências dos utilizadores, tornando a informação mais acessível, pelo que a sua disponibilização na Internet pareceu um passo lógico nesse sentido. É constituído já por um grande número de níveis correspondentes a temas essenciais do ambiente, os quais são sobreponíveis, possibilitando uma completa base de trabalho para os SIG. [Texto extraído de http://www.apambiente.pt/index.php?ref=19&subref= 174].

1517 Mapas restaurados, analisados, catalogados e digitalizados que a Biblioteca Nacional coloca à disposição, graças ao Projeto Biblioteca Virtual da Cartografia Histórica dos Séculos XVI a XVIII. Informações únicas sobre a expansão territorial nos vários continentes estarão doravante ao alcance tanto da comunidade científica nacional e internacional quanto do grande público. [Texto extraído de http://consorcio.bn.br/ cartografia/apresentacao.html. Autoria: Moniz Sodré].

The heat waves of 2003 in Western Europe and 2010 in Russia, commonly labelled as rare climatic anomalies outside of previous experience, are often taken as harbingers of more frequent extremes in the global warming-influenced future. However, a recent reconstruction of spring–summer temperatures for WE resulted in the likelihood of significantly higher temperatures in 1540. In order to check the plausibility of this result we investigated the severity of the 1540 drought by putting forward the argument of the known soil desiccation-temperature feedback. Based on more than 300 first-hand documentary weather report sources originating from an area of 2 to 3 million km2, we show that Europe was affected by an unprecedented 11-month-long Megadrought. The estimated number of precipitation days and precipitation amount for Central and Western Europe in 1540 is significantly lower than the 100-year minima of the instrumental measurement period for spring, summer and autumn. This result is supported by independent documentary evidence about extremely low river flows and Europe-wide wild-, forest- and settlement fires. We found that an event of this severity cannot be simulated by state-of-the-art climate models.

The paper reports the results of the analysis of the 14 longest precipitation instrumental series, covering the last 300 years, that have been recovered in six subareas of the Western Mediterranean basin, i.e., Portugal, Northern and Southern Spain, Southern France, Northern and Southern Italy. This study extends back by one century our knowledge about the instrumental precipitation over the Western Mediterranean, and by two centuries in some specific subareas. All the time series show repeated swings. No specific trends have been found over the whole period, except in a few cases, but with modest time changes and sometimes having opposite tendency. The same can be said for the most recent decades although with some more marked departures from the average. The correlation between the various Mediterranean subareas is generally not significant, or almost uncorrelated. The Wavelet Spectral Analysis applied to the precipitation identifies only a minor 56-year cycle in autumn, i.e., the same return period that has been found in literature for the Sea Surface Temperature over North Atlantic. A comparison with a gridded dataset reconstruction based on mixed multiproxy and instrumental observations, shows that the grid reconstruction is in good agreement with the observed data for the period after 1900, less for the previous period.

Natural proxies, documentary evidence and instrumental data are the only sources used to reconstruct past climates. In this paper, we present the 18th century meteorologists (either Portuguese or foreigners) who made the first observations at several sites in Continental Portugal, Madeira Island and Rio de Janeiro (Brazil), from 1749 until 1802. Information is given concerning observation site, variables observed, measurement period, methods of measurements and sources (both manuscript and printed). Some examples from the data usefulness are given: rainfall variability in Madeira (1749–1753) and in continental Portugal (1781–1793) was reconstructed, allowing to extend towards the late 18th century the well known negative correlation between the NAO index and seasonal rainfall. Furthermore, previously unpublished data for 1783–1784 have allowed analysing the consequences of the Lakagígar eruption in Portugal: foggy and haze days are referred to in summer 1783, but unlike the hot summer observed in northern and central Europe, temperatures in Portugal were lower than average. Additionally, observations from Rio de Janeiro in Brazil show that the Lakagígar consequences may well have spread to sectors of the Southern Hemisphere. Although the series are short, the data have been used for climate reconstruction studies and may also be useful to improve the quality of large scale reconstruction datasets.