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Documentary climate data describe evidence of past climate arising from predominantly written historical documents such as diaries, chronicles, newspapers, or logbooks. Over the past decades, historians and climatologists have generated numerous document-based time series of local and regional climates. However, a global dataset of documentary climate time series has never been compiled, and documentary data are rarely used in large-scale climate reconstructions. Here, we present the first global multi-variable collection of documentary climate records. The dataset DOCU-CLIM comprises 621 time series (both published and hitherto unpublished) providing information on historical variations in temperature, precipitation, and wind regime. The series are evaluated by formulating proxy forward models (i.e., predicting the documentary observations from climate fields) in an overlapping period. Results show strong correlations, particularly for the temperature-sensitive series. Correlations are somewhat lower for precipitation-sensitive series. Overall, we ascribe considerable potential to documentary records as climate data, especially in regions and seasons not well represented by early instrumental data and palaeoclimate proxies.

Trabajo presentado a la XXXVI Reunión Bienal de la Real Sociedad Española de Física, celebrada en Santiago de Compostela (España) del 17 al 21 de julio de 2017., In this study we examine the outstanding characteristics of the strong 2015–2016 El Niño (EN), one of the strongest in record, and its impact over the European region through the stratospheric pathway. Despite being classified as a strong eastern Pacific (EP) EN event, our analysis reveals its complex nature, with some signatures that are more typical of central Pacific (CP) EN events instead. The CP-EN behavior of this event is based on first, the value of the CP index, which reached a historical record. Second, the polar stratospheric signal, as a stronger and colder polar vortex in early and mid-winter in relation to reduced upward wave propagation and a weak Aleutian low; which resembles the typical behavior reported for CP-EN. Third, the occurrence of one of the earliest Stratospheric Final Warmings (SFWs) on record; which are found to be more prone to occur during CP-EN than EP-EN events. In addition, anomalies following the SFW descended from the stratosphere into the troposphere and influenced the surface weather during spring. Thus, persistent blocking conditions over Greenland diverted the Atlantic storm-tracks to the south, resulting in above-normal precipitation over southern Europe. These results highlight the importance of considering early SFWs as mediators in El Niño teleconnections., This work was supported by the Spanish Ministry of Economy and Competitiveness through the PALEOSTRAT (CGL2015-69699-R) project and the European Project 603557-STRATOCLIM under program FP7-ENV.2013.6.1-2. F.M. Palmeiro was funded by grant BES-2013-063906

In this study, we analyze the linkage between atmosphere and ocean modes and winter flood variability over the 20th century based on long‐term flow‐discharge series, historical archives, and tree‐ring records of past floods in the North Atlantic Basin (NAB). The most extreme winter floods occurred in 1936 and had strong impacts on either side of the Atlantic. We hypothesize that the joint effects of sea surface temperatures (SSTs) over the Atlantic and Pacific Oceans and the Arctic Oscillation (AO), which is closely related to the North Atlantic Oscillation, play a significant role when describing flood variability in North America and Europe since 1900. Statistical modeling supports the assumption that the response of flood anomalies over the NAB to AO phases is subsidiary of SST phases. Besides, we shed light on the extraordinarily winter flood of 1936 that was characterized by very high SSTs over both the Atlantic and Pacific (>98th percentile) and very low, negative values of AO (, This study was funded by the Institute for Environmental Sciences (University of Geneva) without any specific grant. S.B. acknowledges support from the FP7 project ERA‐CLIM2. J.A.B.C. thanks Sebastian Guillet, Christophe Corona, and Jaime Madrigal for their comments. G.B. appreciates the support of Fundación Biodiversidad (MITECO) through research project DAM‐ADAPT. D.B. and R.G.‐H. were supported by the Spanish Ministry of Economy and Competitiveness through the PALEOSTRAT (CGL2015‐69699‐R) project and the European Project 603557‐STRATOCLIM under program FP7‐ENV.2013.6.1‐2.

Trabajo presentado en el AGU (American Geophysical Union) Fall Meeting: Advancing Earth and Space Science, celebrado en Washington D.C. (Estados Unidos), del 10 al 14 de diciembre de 2018, near-surface wind speed, which strongly depends on the local setting of the observational sites and the boundary layer parameterizations within the reanalysis model. There is considerable spatial heterogeneity in stagnation patterns (i.e. occurrence of stagnation days and events, duration of events) over the area of study. Therefore, we have used the k-means algorithm to regionalise the monthly frequency of stagnant days, obtaining five regions: Scandinavia (SCAN), Northern-Europe (NEU), Central-Europe (CEU), South-West (SW) and South-East (SE). The northern regions (SCAN and NEU) present low frequency of stagnation compared to the southern regions (SW and SE). We will present additional results from the temporal variability and synoptic patterns associated with air stagnation in these regions. Finally, we have assessed the impact of air stagnation on air quality. This is particularly strong over CEU. In this region, the anomalies of summer ozone and winter PM10 on stagnant vs. non-stagnant days exceed 20% and 50%, respectively. Persistent, widespread stagnation events have also been found to favour the build-up of these pollutants over most of the continent. We will discuss the distinct impacts of stagnation on both pollutants over the different regions, considering the main processes at play.

Trabajo presentado en el ESA Consultation for a Regional Initiative over the Mediterranean - MED, celebrado en Frascati (Italia), del 11 al 12 de diciembre de 2018, The Geosciences Institute (IGEO: http://www.igeo.ucm-csic.es/en/igeo) is a joint center of the Spanish Research Council (CSIC) -the largest public institution dedicated to research in Spain- and the Complutense University (UCM) –the largest university in Spain- carrying out cutting-edge research related to Geology, Geodesy and Geophysics using a multidisciplinary approach. The aim of this poster is to show the main research lines and needs of the IGEO directly linked to the priorities addressed in the MED 2018 consultation meeting. We shall present those of our current activities which are more suited to contribute to the Atmospheric science and applications theme -particularly in the coupled feedback atmosphere/ocean/continental surfaces section- but also have strong impact in both Ocean Science and Land Science (e.g. geoinformation systems, Climate impacts on land environment,…) themes. Some examples of IGEO’s capabilities include satellite observation (e.g., InSAR, optical, gravity and magnetic), combined with in situ data, land instability and deformation as well as structures and infrastructures instability, associated to geological and antropogenic hazards. We have also developed and implemented techniques for interpretation and modeling and the different level observation and results can be implemented and distributed using the European Plate Observing System (EPOS) ESFRI infrastructure. From the climate view point, additional our main priorities should be focused on: 1) Detection of weather regimes and synoptic systems with automatic methods to better understand the atmospheric circulation variability and change, 2) Weather and climate extreme events from different perspectives, including climate change attribution to human activities, and 3) Effect of weather regimes on air pollutants such as ozone and particulate matter to establish links between atmospheric composition and circulation. IGEO is included into CSIC's Natural Resources Research Area, which gathers nearly 20 research institutes, including various singular facilities (e.g. Doñana Biological Station (EBD: http://www.ebd.csic.es) or Mediterranean Institute of Advanced Research (IMEDEA: http://imedea.uib-csic.es/centre.php), and specialized centers (e.g. Ebro Observatory (OE: http://www.obsebre.es/). We shall also provide a brief overview of the activities, projects and initiatives carried out at CSIC where ESA's EO may definitively contribute.

Wet and dry extremes in Quito (Ecuador) over the last 400 years are studied using two sources of information: the longest available instrumental rainfall series in northern South America (1891–2015) and the rogation ceremonies recorded in the Chapter Acts of Quito (1600–1822). The rogation ceremonies present a seasonal distribution that is related to the crops and to the typical distribution of rainfall over the year. August was the month with most pro serenitate rogations because farmers needed dry conditions for harvest, whereas excess rainfall at this time would lead to rotting and loss of the harvest. The pro pluvia rogations were markedly more frequent during January and February when farmers needed rain for sowing. This relationship between climate and farming activities makes Quito's rogations a good proxy for drought and extreme wet conditions during January–February–March (JFM) and wet conditions during June–July–August (JJA). Standardized precipitation index (SPI) was computed for the instrumental period. The 3‐month SPI showed a significant linear trend over the last 125 years (−0.4 per decade, p = 0.009). The five wettest periods were 1651–1657, 1663–1669, 1913–1919, 1950–1956, and 1981–1985. Droughts have intensified in frequency and length since the middle of the 20th century. The most important drought periods were 1692–1701, 1718–1723, 1976–1980, 1990–1993, and 2001–2006. The severest drought during the last 400 years occurred in 1692–1701 when a great famine devastated Quito and affected most of the central Andes., This work was supported by the project PROMETEO, Secretariat of Higher Learning, Science, Technology and Innovation (Ecuador Government). The authors want to thank the EU and Spanish Ministry of Economy and Competitiveness for funding within the framework of the collaborative international consortium IMDROFLOOD financed under the ERA‐NET Cofund WaterWorks2014 Call, an integral part of the 2015 Joint Activities conducted by the Water Challenges for a Changing World Joint Programme Initiative (Water JPI).

Trabajo presentado en la European Geosciences Union General Assembly, celebrada en Viena (Austria), del 8 al 13 de abril de 2018, Ships’ logbooks are the most important source of wind direction observations over the world’s oceans and seas for the pre-instrumental period. Moreover, wind direction in the English Channel is informative about the mid-latitude atmospheric circulation over the Atlantic and plays an important role in the climate conditions of Europe. We present four monthly indices of wind persistence, one for each cardinal direction: Northerly (NI), Easterly (EI), Southerly (SI) and Westerly (WI), based on daily observations taken aboard ships over the English Channel. These directional indices (DIs) are the longest observational record of atmospheric circulation to date, covering the 1685-2014 period. We show that the DIs constitute a powerful tool to characterize the atmospheric circulation over Europe from monthly to multidecadal time scales. Thus, they present a coherent climatic signal in terms of temperature and precipitation over most of Europe with zonal indices (WI-EI) affecting larger areas than meridional indices (NI-SI), especially during cold seasons. In fact, statistical models including all DIs are able to explain a considerable amount of climate variability, improving in most cases that accounted for by the North Atlantic Oscillation (NAO). Moreover, the combination of DIs is able to capture the non-stationarity of the NAO. In this sense, we report multidecadal fluctuations during the last centuries between a “high-zonal” and “low-zonal” dipole of the NAO, with no discernible trend for the last 330 years. These results show the potential of DIs to study European climate variability and its responses to slowly-varying climate drivers, as well as anthropogenic and natural forcings., This work was supported by FCT through project UID/GEO/ 50019/2013

Trabajo presentado en la European Geosciences Union General Assembly, celebrada en Viena (Austria), del 8 al 13 de abril de 2018, This work examines the exceptional characteristics of the mega-heatwave that affected western and central Europe in June 2017. A novel algorithm was designed to track the spatio-temporal evolution of extreme temperature patterns, being particularly well suited to monitor mega-heatwaves. We show that the intensity, extension and persistence of the June 2017 event were comparable to those of historical European mega-heatwaves but it occurred earlier. The most affected area was south-western Europe, where the event was the longest heatwave of the reanalysis period, and caused the warmest temperatures from daily to seasonal scales, devastating forest fires and human casualties. The peak of the mega-heatwave was characterized by an unprecedented subtropical warm air intrusion due to a record-breaking subtropical ridge that displayed signatures closer to those of July and August ridges. Using the analogue method, we found that the atmospheric circulation was the main triggering factor of the event. Nevertheless, the recorded temperature anomalies were higher than those expected from past flow analogues and thermodynamical changes of the last decades made a substantial contribution to the exceptionality of the event. This episode could be an actual manifestation of summers that are becoming longer and with an earlier occurrence of high-summer mega-heatwaves.

Trabajo presentado en las 5ª Journée Climat et Impacts (2018), celebradas en Orsay (Francia), del 29 al 30 de noviembre de 2018, This work examines the global warming contribution to mega-heatwaves in western Europe. The exceptional June 2017 mega-heatwave (which affected western and central Europe) was used as a case study. This event shows that mega-heatwaves are not only more frequent and intense than in the past, but also are extending to earlier dates. So the associated mega-heatwave impacts (record-breaking temperatures, devasting wildfires, human causalities and economical losses) are extending out of high-summer. Using the analogue method, we found that a record-breaking subtropical ridge was the main triggering factor. However, the thermodynamical changes of the last decades made a substantial contribution to the exceptionality of the event.

Trabajo presentado en la European Geosciences Union General Assembly, celebrada en Viena (Austria), del 8 al 13 de abril de 2018, During 2016-2017, most of Western Europe has suffered a major drought. Associated impacts have been reported for a number of socio-economic sectors. Crops have been severely affected with the resulting reduction in agricultural production, especially for cereals, olives and almonds in Spain and Italy. Devastating fires in southern Europe have led to the evacuation of thousands of people and even human fatalities in Portugal. The energy sector has also been significantly impacted partly due to the drop in hydroelectrical production, which reached a ∼50% decrease in Spain and coincided with minimum wind energy production, rising the electricity bill to historical maxima. The standardised precipitation-evapotranspiration index (SPEI) is used to diagnose this major drought. It is compared to the standardized precipitation index (SPI) in order to highlight the contribution of meteorological variables other than precipitation. The results of the SPEI show that July 2016 - June 2017 has been the most severe 12-month drought of the reanalysis period over Western Europe. Unlike most mega-droughts in Europe, the event is characterized by an unusual spatial pattern, with dry conditions over northern and southern Europe. In fact, several countries such as France, Spain or Germany have experienced a record-breaking drought simultaneously. Nevertheless, the analysis of the SPI, which only accounts for the precipitation deficit, suggests that this has not been the driest event on record. Given the discrepancies between the results found for both drought indices, we focus on analysing individually the variables controlling evapotranspiration to understand their relative roles. Moreover, the atmospheric circulation and moisture sources have been explored during the driest months in order to assess the role of synoptic patterns in the spatio-temporal evolution of the drought.

Trabajo presentado en la EGU General Assembly 2016 (European Geosciences Union), celebrada en Viena del 17 al 22 de abril de 2016, The concept of the Western North Pacific Summer Monsoon (WNPSM) appeared for the first time in 1987. It is, unlike the Indian Summer Monsoon (ISM) and the East Asian summer monsoon (EASM), an oceanic monsoon mostly driven by the meridional gradient of sea surface temperature. Its circulation is characterized by a northwest-southeast oriented monsoon trough with intense precipitation and low-level southwesterlies and upper-tropospheric easterlies in the region [100º-130º E, 5º-15ºN]. Up to now, the primary index to characterize the WNPSM has been the Western North Pacific Monsoon Index (WNPMI) which covers the 1949-2013 period. The original WNPMI was defined as the difference of 850-hPa westerlies between two regions: D1 [5º–15ºN, 100º–130ºE] and D2 [20º–30ºN, 110º–140ºE]. Both domains are included in the main historical ship routes circumnavigating Asia for hundreds of years. Many of the logbooks of these ships have been preserved in historical archives and they usually contain daily observations of wind force and direction. Therefore, it has been possible to compute a new index of instrumental character, which reconstructs the WNPSM back to the middle of the 19th Century, by using solely historical wind direction records preserved in logbooks. We define the monthly Western North Pacific Directional Index (WNPDI) as the sum of the persistence of the low-level westerly winds in D1 and easterly winds in D2. The advantages of this new index are its nature (instrumental) and its length (1849-2013), which is 100 years longer than the WNPMI (which was based on reanalysis data). Our WNPDI shows a high correlation (r=+0.87, p, This research was funded by the Spanish Ministerio de Economía y Competitividad through the project INCITE (CGL2013-44530-P, BES-2014-069733).

Trabajo presentado en el 8th EGU Leonardo Conference, celebrado en Orense (España), del 25 al 27 de octubre de 2016, The concept ofthe Western North Pacific Summer Monsoon (WNPSM) appeared forthe firsttime in 1987. It is, unlike the Indian Summer Monsoon (ISM) and the East Asian summer monsoon (EASM), an oceanic monsoon driven fundamentally by the meridional gradient of sea surface temperature. Its circulation is characterized by a northwestsoutheast oriented monsoon trough with intense precipitation and lowlevel southwesterlies and upper-tropospheric easterlies in the region [100º-130º E, 5º-15ºN]. By using solely daily observations of wind direction from ships' logbooks which circumnavigated Asia for hundreds of years, it has been possible to compute a new index, the Western North Pacific Directional Index (WNPDI), to reconstruct the WNPSM back to the middle of the 19th Century. The WNPDI is defined as the sum ofthe persistence ofthe low-level westerly winds in [5º–15ºN,100º–130ºE] and easterly winds in [20º–30ºN, 110º–140ºE]. It is an instrumental index and widens almost 100 years the Western North Pacific Monsoon Index (WNPMI), an primary index based on reanalysis data which characterises the WNPSM throughout the 1949-2013 period. Both indices show a high correlation (r=+0.87, p, This research was funded by the Spanish Ministerio de Economía y Competitividad through the projects CGL2013-44530-P and CGL2014-51721-REDT and the grant BES-2014-069733

Trabajo presentado en el 8th EGU Leonardo Conference, celebrado en Orense (España), del 25 al 27 de octubre de 2016, The precipitation associated to the West African Monsoon is strongly modulated by the oceanatmosphere interaction in the tropical North Atlantic. During the last four decades, this monsoon has experienced a strong decline in its strength which has resulted in large shortages of precipitation in populated areas such as the Sahel, with the consequent humanitarian crisis. The improvement of our understanding of the long term variability of this monsoon and its relation to its moisture sources is therefore, of paramount importance. The historical evolution of the West African Monsoon has been usually addressed by combining instrumental precipitation series in northwest Africa. Unfortunately,reliable meteorological series in this region are only available since the beginning of the 20th Century thus limiting our understanding of the significance of the unusually persistent drought period. As most of the moisture involved in the generation of monsoonal precipitations came from the ocean, it is feasible the construction of an index characterising the monsoon strength by using wind records. In this work, by using exclusively wind direction measures taken aboard thousands of sailing ships circumnavigating Africa, we have assembled a new index measuring the strength of the West African Monson since 1839. Our new reconstruction has evidenced for the first time, that this monsoon can experience persistent periods of high activity, as it seems to have occurred between 1840 and 1890. Additionally, we have been able to study the relation of the West African Monsoon with several climatic patterns. Ourresults suggests that since the beginning ofthe weak monsoon period starting in the 1970s, the correlations with different climatic patterns such as the Atlantic “El Niño” have changed significantly in relation to those of the previous century., This research was funded by the Spanish Ministerio de Economía y Competitividad through the projects CGL2013-44530-P and CGL2014-51721-REDT

Trabajo presentado en la EGU General Assembly 2016 (European Geosciences Union), celebrada en Viena del 17 al 22 de abril de 2016., The precipitation in the Sahel –which is mainly controlled by the dynamics of the West African Monsoon-, has been in the spot of the climate community for the last three decades due to the persistence of the drought period that started in the 1970s. Unfortunately, reliable meteorological series in this area are only available since the beginning of the 20th Century, thus limiting our understanding of the significance of this period from a long term perspective. Currently, our knowledge of what happened in times previous to the 20th Century essentially relies in documentary or proxy sources. In this work, we present the first instrumental evidence of a 50 year-long period characterised by an unusually strong West African monsoon in the19th Century. Following the recent advances in the generation of climatic indices based on data from ship’s logbooks, we used historical wind observations to compute a new index (the so-called ASWI) for characterising the strength of the West African Monsoon. The ASWI is based in the persistence of the southwesterly winds in the [29ºW17ºW;7ºN-13ºN] area and it has been possible to compute it since 1790 for July and since 1839 for August and September. We show that the ASWI is a reliable measure of the monsoon’s strength and the Sahelian rainfall. Our new series clearly shows the well-known drought period starting in the 1970s. During this dry period, the West African Monsoon was particularly weak and interestingly, we found that since then, the correlations with different climatic patterns such as the Pacific and Atlantic “El Niño” changed significantly in relation to those of the previous century. Remarkably, our results also show that the period 1839-1890 was characterised by an unusually strong and persistent monsoon. Notwithstanding, two of the few dry years within this period were concurrent with large volcanic eruptions in the Northern Hemisphere. This latter result supports the recently suggested relationship between major volcanic eruptions with large aerosol loads in the northern hemisphere stratosphere and the occurrence of isolated drought episodes in the Sahel., This research was funded by the Spanish Ministerio de Economía y Competitividad through the projects CGL2013-44530-P and CGL2014-51721-REDT

Trabajo presentado en el WCRP/SPARC workshop: Challenges for Climate Science – Synergies between SPARC and the WCRP Grand Challenges, celebrado en Berlin (Alemania), del 31 de octubre al 1 de noviembre de 2016, Recent studies have demonstrated the influence of the stratosphere on the climate. However, the limited period of instrumental observations prevents us from obtaining a clear picture of role of the stratosphere in modulating the climate responses to internal (e.g., El Niño Southern Oscillation) and external (e.g., volcanic) forcings, and its contribution to explain anomalous periods before the industrial era. PALEOSTRAT (PALEOmodelization from a STRATospheric perspective) is a funded project by the Spanish government which will investigate the impact of the stratosphere on the climate of the Last Millennium (LM), with focus on the preindustrial era (850-1850 CE). This will be addressed by means of a suite of LM simulations with the CESM model which only differ in the representation of the stratosphere, so that their comparisons will unambiguously quantify the impact of the middle-atmosphere on the surface climate. Uncertainties related to external forcings will also be addressed by comparing business-as-usual LM model simulations with LM runs forced with novel external forcing histories and innovative model implementations, which include an explicit representation of volcanic aerosols and their evolution following major eruptions. PALEOSTRAT will also offer an unprecedented opportunity to explore the vertical coupling on multidecadal and longer time scales., PALEOSTRAT (CGL2015-69699-R) is funded by the Spanish Ministry of Economy and Competitiveness (MINECO)

Trabajo presentado en la EGU General Assembly 2016 (European Geosciences Union), celebrada en Viena del 17 al 22 de abril de 2016., The meteorological observations found in old ships’ logbooks have been recognized as a useful source of climatic information in periods and areas not covered by other sources. In the last five years several studies have employed the wind direction observations contained in logbooks to generate climatic indices of instrumental character related to large scale patterns such as the atmospheric westerly circulation in North Atlantic, the strength of the West African Monsoon or the start date of the Indian Summer Monsoon (ISM). This study is focused on the winds in the eastern Mediterranean (EM) and its relation to the subtropical climate at decadal scale. Previous studies have shown a significant link between the frequency and strength of the prevalent summer northerly winds (Etesian winds) of the EM and the strength of the ISM. This relationship had only been studied in detail for the second half of the 20th century due to the absence of long and continuous series of wind observations in the EM for previous periods. In this work, we use historical wind data contained in ship’s logbooks to generate a new climatic index, the “Etesian Wind Index”, which can be defined as the percentage of days with prevalent northerly wind (between 315º and 45º) in a fixed region [10ºW-20ºW, 32ºN-36ºN]. We have been able to produce an index of the Etesian winds starting in 1877 suitable to analyze its long term variability and its relation with the ISM in unprecedented detail. Our first results show that the frequency of the northerly winds in the EM was significantly larger in the first half of the studied period, mainly due to an intensification of the zonal component in the second half of the studied period. Interestingly, the comparison with analogous Etesian wind indices computed from reanalysis products (NCEP/NCAR 20th Century (V2c) and ERA20C), shows strong discrepancies among them and with our instrumental reconstruction, which could indicate a misrepresentation of the Etesian winds in the reanalysis products prior to 1948. Accordingly to previous works, we have found a strong and significant positive correlation between the Etesian Wind Index and the ISM since 1950 to 2013. This link is also shown for the 1877-1900 period. However the correlation fades out in the period 1900-1950 , even reversing its sign in the central part of the latter period. The origin and causes of this change is still under research., This research was funded by the Spanish Ministerio de Economia y Competitividad through the project INCITE (CGL2013-44530-P, BES-2014-069733)

Trabajo presentado en el 2nd International Workshop on Maritime Flows and Networks, celebrado en París (Francia), del 25 al 27 de abril de 2016, Since the early times of sail navigation, weather and climate conditioned shipping routes and dates. Thus, the transatlantic ships tried to avoid the Azores High Pressure Center to prevent getting stack in the middle of the dead calms and suffering starvation and scurvy. The hurricanes seasonality (with peak activity between June and November) dictated the traveling dates to and from the Caribbean. For the travel back to Europe, navigation profited from the Atlantic westerlies regularity. In the Indian Ocean, the English and Dutch trade with India and Indonesia was adapted to the Asian monsoon seasonal cycle. These few examples illustrate how ships depended on weather and climate. Lives and properties onboard relied on the ability of captains, officers and crew to scrutinize and interpret weather and sea. Consequently, weather observation was one of the most important topics in the training of seamen. Due to this relevance, the content of the ship logbooks (a legal document recording the main facts occurred on board) included thorough daily or even hourly records on weather and sea conditions, including wind force and direction, cloud cover, precipitation, sea estate and currents. Fortunately, dozens of thousands of these logbooks have been preserved in different archives, mostly in Europe (Wheeler and García-Herrera 2008). Although meteorological instruments were systematically onboard only after the Brussels Conference in 1853, it has been shown that wind observations are reliable and comparable to the modern records since the 17th century (García-Herrera et al 2005). These observations are highly valuable because they cover a period of centuries when climate was only modulated by natural forcings and extend into the industrial era when human emissions of strong anthropogenic Greenhouse Gases emissions. Additionally, they are the only known source of meteorological observations over the world’s Oceans for the pre-instrumental era In this presentation we will show how these records can be used to build centennial long indices able to characterize the behavior of different climate phenomena. The records from the Manila Galleon (a commercial route connecting Manila and Acapulco for more than 250 years) will help to unveil secular trends in the behavior of the Pacific monsoon through (García et al 2001). Wind records from the English Channel will be used to construct the longest instrumental series of atmospheric circulation over the Atlantic, which allows to characterize climate variability over Europe since the end of the 17th century (Barriopedro et al, 2014), and the influence of wind circulation anomalies on the occurrence of European extreme precipitation and temperature events. Finally, we will show how the observations of the ships connecting Europe with their African and Asian colonies can be used to build the first objective records of the West African Monsoon strength and the Indian Summer Monsoon onset since the 19th century (Gallego et al 2015). These are just some examples of the climatic potential of ship logbooks records. Only a joint effort between historians, seamen, meteorologists and climatologists could fully exploit all the possibilities kept in the archives towards a better understanding of past climates and future changes.

Trabajo presentado en el HyMeX Workshop on Drought and Water Resources, celebrado en Zaragoza (España), del 5 al 7 de abril de 2016

The study of the wind power output variability comprises different time scales. Among these, low-frequency variations can substantially modify the performance of a wind power plant during its lifetime. In recent years, other temporal scales such as the short-term variability or the climatological conditions of wind and the corresponding generated power have been investigated in depth. However, the study of longer decadal and multidecadal variations is still in its early stages. In this work, the wind power output long-term variability is analysed for two locations in Spain, during the period 1871–2009. This is attained by computing the annual wind speed probability density functions derived from an ensemble of atmospheric sea level pressure data set through a statistical downscaling based in evolutionary algorithms. Results reveal significant trends and periodicities in multidecadal bands including 13, 25 and 46 years, as well as significant differences among both sites. The impact of the leading large-scale circulation patterns (NAO, EA, SCAND and AMO) on wind power output and its stationarity is analysed. Results on both locations show non-stationary significant and opposite seasonal couplings with these forcings. Finally, the long-term variability of the reconstructed Weibull parameters of the annual wind speed distributions is used to derive a linear model to estimate the annual wind power., This work has been supported by the research framework established between STREAM group at University Complutense of Madrid and Iberdrola Renovables Energía S.A.

Attribution of extreme events is a challenging science and one that is currently undergoing considerable evolution. In this paper are 19 analyses by 18 different research groups, often using quite different methodologies, of 12 extreme events that occurred in 2012. In addition to investigating the causes of these extreme events, the multiple analyses of four of the events, the high temperatures in the United States, the record low levels of Arctic sea ice, and the heavy rain in northern Europe and eastern Australia, provide an opportunity to compare and contrast the strengths and weaknesses of the various methodologies. The differences also provide insights into the structural uncertainty of event attribution, that is, the uncertainty that arises directly from the differences in analysis methodology. In these cases, there was considerable agreement between the different assessments of the same event. However, different events had very different causes. Approximately half the analyses found some evidence that anthropogenically caused climate change was a contributing factor to the extreme event examined, though the effects of natural fluctuations of weather and climate on the evolution of many of the extreme events played key roles as well.

In this study, seasonal and interannual variability of the main atmospheric moisture sources over eight regions in the Mediterranean basin were investigated along a 21 year period. The Lagrangian dispersion model FLEXPART, developed by Stohl and James [2004, 2005], was applied to identify the contribution of humidity to the moisture budget of each region. This methodology is used to compute budgets of evaporation minus precipitation (E - P) by calculating changes in the specific humidity along backward trajectories, for the preceding 10 day periods. The results show clear seasonal differences in the moisture sources between wet and dry seasons. The Western Mediterranean Sea is the dominant moisture source for almost all the regions in the Mediterranean basin during the wet season, while the local net evaporation dominates during the dry season. The highest interannual variability is found in contributions to the Iberian Peninsula, Italy, and the Eastern Mediterranean. It is seen that the role of teleconnections is more limited than for the precipitation recorded in the region. Key Points The seasonal variability of moisture sources in the Mediterranean was studied Moisture sources show in general a seasonal variability The interannual variability is limited ©2013. American Geophysical Union. All Rights Reserved.

The atmospheric response to the 11 year solar cycle (SC) and its combination with the quasi-biennal oscillation (QBO) are analyzed in four simulations of the Whole Atmosphere Community Climate Model version 3.5 (WACCM3.5), which were performed with observed sea surface temperatures, volcanic eruptions, greenhouse gases, and a nudged QBO. The analysis focuses on the annual mean response of the model to the SC and on the evolution of the solar signal during the Northern Hemispheric winter. WACCM3.5 simulates a significantly warmer stratosphere under solar maximum conditions compared to solar minimum. The vertical structure of the signal in temperature and ozone at low latitudes agrees with observations better than previous versions of the model. The temperature and wind response in the extratropics is more uncertain because of its seasonal dependence and the large dynamical variability of the polar vortex. However, all four simulations reproduce the observed downward propagation of zonal wind anomalies from the upper stratosphere to the lower stratosphere during boreal winter resulting from solar-induced modulation of the polar night jet and the Brewer-Dobson circulation. Combined QBO-SC effects in the extratropics are consistent with observations, but they are not robust across the ensemble members. During boreal winter, solar signals are also found in tropospheric circulation and surface temperature. Overall, these results confirm the plausibility of proposed dynamical mechanisms driving the atmospheric response to the SC. The improvement of the model climatology and variability in the polar stratosphere is the basis for the success in simulating the evolution and magnitude of the solar signal.

Programa de doctorado: Sanidad animal. Los objetivos de esta tesis son: 1.- Realizar el análisis histopatológico de los cambios asociados con el rechazo crónico en el modelo de trasplante pulmonar experimental en ratas. 2.- Identificar, mediante microarrays de ADN, todos los cambios en expresión de genes asociados con el rechazo crónico en el pulmón trasplantado. 3.- Realizar la clasificación funcional de los cambios de expresión génica como estrategia para identificar los mecanismos moleculares asociados con el rechazo crónico en el pulmón trasplantado. 4.- Cuantificar la expresión génica, mediante PCR en tiempo real, de algunos genes asociados con el rechazo crónico en el pulmón trasplantado.

Records of taxes collected during the seventeenth and eighteenth centuries contribute to understanding of climatic variability of the subtropical North Atlantic region. Historical documentary sources in the Canary Islands have been used to construct cereal production series for the period 1595–1836. The cereal growth period in this region covers essentially the rainy season, making these crops adequate to characterize the annual precipitation. A proxy for the Islands' rainfall based on the historical series of wheat and barley production has been constructed and assessed by using two independent series of dry and wet years. The spectral analysis of the crop production reveals a strong non stationary behavior. This fact, along with the direct comparison with several reconstructed and instrumental North Atlantic Oscillation series, suggests the potential use of the reconstructed precipitation as a proxy for this climatic oscillation during preinstrumental times.

We show that a separable Banach space X has the Schur property if and only if every separately compact bilinear application from X into c0 is completely continuous, thus answering a question raised by Pełczyński.

In this paper, we develop an instrumental index based on historical wind direction observations aimed to quantify the moisture transport from the tropical Pacific to Central and northern South America at a monthly scale. This transport is mainly driven by the so-called “Chocó jet”, a low-level westerly jet whose core is located at 5∘ N and 80∘ W. The Chocó jet is profoundly related to the dynamics of the Intertropical Convergence Zone in the eastern equatorial Pacific and it is responsible for up to 30 % of the total precipitation in these areas. We have been able to produce an index for this transport starting in the 19th century, adding almost a century of data to previous comparable indices. Our results indicate that the seasonal distribution of the precipitation in Central America has changed throughout the 20th century as a response to the changes in the Chocó jet, decreasing (increasing) its strength in July (September). Additionally, we have found that in general, the relationship between the Chocó jet and the El Niño–Southern Oscillation has been remarkably stable throughout the entire 20th century, a finding particularly significant because the stability of this relation is usually the basis of the hydrologic reconstructions in northern South America., This research was funded by the Spanish Ministerio de Economía y Competitividad through the projects CGL2013-44530-P, CGL2014-51721-REDT and the research group RNM-356 belonging to the “Plan Andaluz de Investigación Desarrollo e Innovación”.

This paper examines the characteristics of the heatwave that affected western and central Europe in June 2017. Using a novel algorithm, we show that its extension, intensity, and persistence were comparable to those of other European mega‐heatwaves, but it occurred earlier in the summer. The most affected area was Iberia, which experienced devastating forest fires with human casualties and the warmest temperatures of the reanalysis period from daily to seasonal scales. The peak of the mega‐heatwave displayed an unprecedented warm air intrusion due to a record‐breaking subtropical ridge with signatures closer to those of July and August. The atmospheric circulation was the main triggering factor of the event. However, thermodynamical changes of the last decades made a substantial contribution to the event, by increasing the likelihood of surpassing high‐temperature thresholds. This episode could be a good example of a coming future, with high‐summer mega‐heatwaves occurring earlier., This work was supported by the Ministerio de Economía y Competitividad through the PALEOSTRAT (CGL2015‐69699‐R) and ISIPEDIA (ERA4CS) (PCIN‐2017‐046) projects. Ricardo M. Trigo and Pedro M. Sousa are supported by project IMDROFLOOD: Improving Drought and Flood Early Warning, Forecast and Mitigation using real‐time hydroclimatic indicators, JPND‐WaterJPI/0004/2014, financed by FCT/MCTES (PIDDAC). A. Sánchez‐Benítez was funded by grant FPU15/03958 from the Ministerio de Educación, Cultura y Deporte (MECD).

This paper analyses for the first time the impact of high-latitude blocks and subtropical ridges on near-surface ozone (O3) in Europe during a 15-year period. For this purpose, a catalogue of blocks and ridges over the Euro–Atlantic region is used together with a gridded dataset of maximum daily 8h running average ozone (MDA8 O3) covering the period 1998–2012. The response of ozone to the location of blocks and ridges with centres in three longitudinal sectors (Atlantic, ATL, 30–0°W; European, EUR, 0–30°E; Russian, RUS, 30–60°E) is examined. The impact of blocks on ozone is regionally and seasonally dependent. In particular, blocks within the EUR sector yield positive ozone anomalies of ∼ 5–10ppb over large parts of central Europe in spring and northern Europe in summer. Over 20 and 30% of the days with blocks in that sector register exceedances of the 90th percentile of the seasonal ozone distribution at many European locations during spring and summer, respectively. The impacts of ridges during those seasons are subtle and more sensitive to their specific location, although they can trigger ozone anomalies above 10ppb in northern Italy and the surrounding countries in summer, eventually exceeding European air quality (AQ) targets. During winter, surface ozone in the north-west of Europe presents completely opposite responses to blocks and ridges. The anticyclonic circulation associated with winter EUR blocking, and to a lesser extent with ATL blocking, yields negative ozone anomalies between −5 and −10ppb over the UK, northern France and the Benelux. Conversely, the enhanced zonal flow around 50–60°N during the occurrence of ATL ridges favours the arrival of background air masses from the Atlantic and the ventilation of the boundary layer, producing positive ozone anomalies of ∼ 5ppb in an area spanning from the British Isles to the northern half of Germany. We also show that multiple linear models on the seasonal frequency of occurrence of these synoptic patterns can explain a considerable fraction of the interannual variability in some winter and summer ozone statistics (mean levels and number of exceedances of the 90th percentile) over some regions of western Europe. Thus, this work provides the first quantitative assessments of the remarkable but distinct impacts that the anticyclonic circulation and the diversion of the zonal flow associated with blocks and ridges exert on surface ozone in Europe. The findings reported here can be exploited in the future to evaluate the modelled responses of ozone to circulation changes within chemical transport models (CTMs) and chemistry–climate models (CCMs)., Carlos Ordóñez acknowledges funding from the Ramón y Cajal Programme of the Spanish Ministerio de Economía y Competitividad under grant RYC-2014-15036.

The global mean temperature has increased by ~1ºC since the preindustrial period (Allen et al., 2018). Global warming is spatially and temporally inhomogeneous, with larger increases for land and specific regions (so-called hot-spots) and seasons, such as the summer warming in the Mediterranean (García-Herrera and Barriopedro, 2018). The increasing trend of mean temperatures has been accompanied by changes in the tails of the distribution, including an increase in the frequency/duration and intensity of heat waves (Acero et al., 2018; Chapman et al., 2019) , as well as the occurrence of new emerging events, also called mega-heat waves. These extreme events, cause severe impacts in socio-economic sectors and population, like extensive crop failures (Fahad et al., 2017), devastating wildfires (Parente et al., 2018), poor air quality (Ordóñez et al., 2010; Rasilla et al., 2019), increased mortality (Kovats and Hajat, 2008), and peaks in energy demand (Newsham and Bowker, 2010)...

[EN] This work analyses the daily data found in a manuscript written in the City of México in the years 1775-1786. For that purpose, the data were transcribed. The literal descriptions were codified into numerical indices. To validate the historical series, the resulting distributions of the hydrometeorological indices were compared against the instrumental data from the Azcapotzalco’s station, the best correlated observatory from today’s City of Mexico stations. We conclude with high reliability that both patterns agree, and thus data from the manuscript can be considered as representative of a similar precipitation regime as today’s, although historical data slightly overestimate the frequency of precipitation. Dry and wet years were analyzed through the analogues method from the instrumental period. We used composites analysis thanks to reanalysis tools, concluding that ENSO, PDO or CLLJ could have modulated rainfall extremes in the historical period, [ES] Este trabajo analiza los datos de tipo diario encontrados en un manuscrito escrito en Ciudad de México en los años 1775-1786. Para tal propósito, los datos fueron transcritos. Las descripciones literales han sido codificadas mediante índices numéricos. Para validar las series históricas, las distribuciones resultantes de los índices hidrometeorológicos se han comparado con datos instrumentales de la estación de Azcapotzalco, la estación mejor correlacionada de todas las presentes hoy en Ciudad de México. Concluimos con una alta confianza que ambos patrones coinciden, y por lo tanto los datos del manuscrito pueden considerarse como representativos de un régimen pluviométrico como el actual, aunque los datos históricos sobreestiman ligeramente la frecuencia de precipitación. Los años secos y húmedos fueron analizados a través del método por análogos a partir del periodo instrumental. Usamos análisis de composites gracias a herramientas de reanálisis, concluyendo que el ENSO, PDO o el CLLJ pudieron haber modulado los extremos de precipitación en el periodo histórico

[EN] Documentary sources represent a key element in past climate reconstruction. Many of these sources have been exploited, especially in Europe. In this paper we have studied the climate in Mexico City during the XVIII century from an unpublished documentary source, a weather diary written by Felipe de Zúñiga y Ontiveros between 1775 and 1786. To this objective, firstly a calibration of the data provided by the diary has been made. Then, the variability of the temperature described in that period and that from the instrumental period have been compared. Finally, a study of the extreme months occurred in the historical period described by the diary has been made, evaluating how the synoptic circulation could have been during those months., [ES] Las fuentes documentales son un elemento clave en la reconstrucción del clima pasado. Muchas de estas fuentes han sido explotadas, sobre todo en Europa. En este trabajo se ha estudiado cómo era el clima en la ciudad de México en el siglo XVIII a partir de una fuente documental inédita hasta ahora, un diario meteorológico escrito por Felipe de Zúñiga y Ontiveros entre 1775 y 1786. Para ello se ha realizado en primer lugar una calibración de los datos aportados por el diario. A continuación, se ha realizado una comparación de la variabilidad de la temperatura descrita en este periodo con la del instrumental. Por último, se han estudiado los meses extremos acontecidos durante el periodo histórico recogido en el diario y se ha evaluado cómo podría haber sido la circulación a escala sinóptica asociada a los mismos.