SPREAD: a high-resolution daily gridded precipitation dataset for Spain – an extreme events frequency and intensity overview

A high-resolution daily gridded precipitation dataset was built from raw data of 12 858 observatories covering a period from 1950 to 2012 in peninsular Spain and 1971 to 2012 in Balearic and Canary islands. The original data were quality-controlled and gaps were filled on each day and location independently. Using the serially complete dataset, a grid with a 5 × 5 km spatial resolution was constructed by estimating daily precipitation amounts and their corresponding uncertainty at each grid node. Daily precipitation estimations were compared to original observations to assess the quality of the gridded dataset. Four daily precipitation indices were computed to characterise the spatial distribution of daily precipitation and nine extreme precipitation indices were used to describe the frequency and intensity of extreme precipitation events. The Mediterranean coast and the Central Range showed the highest frequency and intensity of extreme events, while the number of wet days and dry and wet spells followed a north-west to south-east gradient in peninsular Spain, from high to low values in the number of wet days and wet spells and reverse in dry spells. The use of the total available data in Spain, the independent estimation of precipitation for each day and the high spatial resolution of the grid allowed for a precise spatial and temporal assessment of daily precipitation that is difficult to achieve when using other methods, pre-selected long-term stations or global gridded datasets. SPREAD dataset is publicly available at https://doi.org/10.20350/digitalCSIC/7393

Characterization of the UHI in Zaragoza (Spain) using a quality-controlled hourly sensor-based urban climate network

The study of the urban heat island (UHI) is of great importance in the context of climate change, where increasingly frequent and intense extreme thermal events will generate lethal effects in cities. In this work, we characterize the UHI of the urban area of Zaragoza (Spain) using a thermohygrometric network of hourly observatories composed of 21 sensors, from March 2015 to February 2021. Due to the diversity of urban spaces and the high volume of information (˜ 995, 000 observations), we performed an exhaustive quality control. Incorporating a synoptic analysis to better identify atmospheric situations not recorded by sensors. The results indicate that 1.6% of observations are removed, mainly due to outliers and hourly variability. We demonstrate that the UHI displays the classical center-periphery pattern with intensity values around 2 °C, but with variations due to the urban structure. We also observe seasonal UHI variations that intensify, especially in winter and autumn nights. Finally, this characterization confirms the differences in UHI intensity are due to their structural and climatic characteristics, which can ultimately guide the logical urban planning design of Zaragoza, and other Mediterranean-like cities with a similar urban environment

Modeling tree-growth: Assessing climate suitability of temperate forests growing in Moncayo Natural Park (Spain)

In the past few decades, temperate forests have been negatively altered by numerous anthropogenic activities and by the impact of ongoing climate change. These changes may require management actions to help preserve some forest tree species. In this sense, highly-detailed knowledge of tree growth and survival across territorial and climatic gradients will be important for forest conservation. We developed a novel approach to determine the optimal zones of forest growth and expansion through climate suitability maps, using a dense tree-ring network of four forest species in Moncayo Natural Park and high-resolution climate data. Our results showed that the mixed-effects models developed using climate data and tree size were able to predict between 65 and 80% of growth variability along the climatic gradient. All studied species were influenced by climate, and the relationship between growth and climate significantly differed along the prevailing climate gradient. Moreover, the suitability maps showed that the current species distribution is limited, and their application may serve as a tool for adaptive management in forests subjected to climate change

SLOCLIM: a high-resolution daily gridded precipitation and temperature dataset for Slovenia

We present a new publicly available daily gridded dataset of maximum and minimum temperature and precipitation data covering the whole territory of Slovenia from 1950 to 2018. It represents the great variability of climate at the crossroads between the Mediterranean, Alpine and continental climatic regimes with altitudes between 0-2864ma.s.l. We completely reconstructed (quality control and gap filling) the data for the three variables from 174 observatories (climatological, precipitation and automatic stations) with the original records all over the country. A comprehensive quality control process based on the spatial coherence of the data was applied to the original dataset, and the missing values were estimated for each day and location independently. Using the filled data series, a grid of 1 x 1 km spatial resolution with 20 998 points was created by estimating daily temperatures (minimum and maximum) and precipitation, as well as their corresponding uncertainties at each grid point. In order to show the potential applications, four daily temperature indices and two on precipitation were calculated to describe the spatial distribution of (1) the absolute maximum and minimum temperature, (2) the number of frost days, (3) the number of summer days, (4) the intensity of precipitation and (5) the maximum number of consecutive dry days. The use of all the available information, the complete quality control and the high spatial resolution of the grid allowed for an accurate estimate of precipitation and temperature that represents a precise spatial and temporal distribution of daily temperatures and precipitation in Slovenia. The SLOCLIM dataset is publicly available at https://doi.org/10.5281/zenodo.4108543 and http://www.sloclim.eu (last access: 10 June 2021) and can be cited as Skrk et al. (2020)

Global Temperature Responses to Large Tropical Volcanic Eruptions in Paleo Data Assimilation Products and Climate Model Simulations Over the Last Millennium

Large volcanic eruptions are one of the dominant perturbations to global and regional atmospheric temperatures on timescales of years to decades. Discrepancies remain, however, in the estimated magnitude and persistence of the surface temperature cooling caused by volcanic eruptions, as characterized by paleoclimatic proxies and climate models. We investigate these discrepancies in the context of large tropical eruptions over the Last Millennium using two state-of-the-art data assimilation products, the Paleo Hydrodynamics Data Assimilation product (PHYDA) and the Last Millennium Reanalysis (LMR), and simulations from the National Center for Atmospheric Research Community Earth System Model-Last Millennium Ensemble (NCAR CESM-LME). We find that PHYDA and LMR estimate mean global and hemispheric cooling that is similar in magnitude and persistence once effects from eruptions occurring in short succession are removed. The estimates also compare well to Northern-Hemisphere reconstructions based solely or partially on tree-ring density, which have been proposed as the most accurate proxy estimates of surface cooling due to volcanism. All proxy-based estimates also agree well with the magnitude of the mean cooling simulated by the CESM-LME. Differences remain, however, in the spatial patterns of the temperature responses in the PHYDA, LMR, and the CESM-LME. The duration of cooling anomalies also persists for several years longer in the PHYDA and LMR relative to the CESM-LME. Our results demonstrate progress in resolving discrepancies between proxy- and model-based estimates of temperature responses to volcanism, but also indicate these estimates must be further reconciled to better characterize the risks of future volcanic eruptions

Climatic drivers of the historical variations in cereal prices in the northeast of the Iberian peninsula in the 17th century

The 17th century knew in Spain several periods of agricultural crisis producing shortages in staple foods and a rising in grain prices. The fluctuations of the prices of wheat, barley and rye are relatively well documented in several areas of the country, however, the knowledge about the influence of climatic and environmental factors on these variations is still limited. In this work, we present the historical records of grain prices of four cities of different geographical areas in northeastern Iberian Peninsula during period 1630-1660, and they are compared with drought indices, reconstructed from documentary and dendroclimatic proxies. We observed that prices variations coincide with regional anomalies in spring-summer drought. Direct correlations between them are low (0.435), however, if analysis is focused on extreme values, the climatic influence is higher: prices are high during dry periods and lower during wet periods. This correspondence is higher in previous and following years to the Guerra dels Segadors, showing that the exchange of goods and the coherence of data were controlled by sociopolitical and environmental factors, being the latter more influential in peacetime. ©2021 José M. Cuadrat, Francisco J. Alfaro Pérez, Ernesto Tejedor Vargas, Mariano Barriendos, Roberto Serrano-Notivoli, Miguel Á. Saz Sánche

Modelización espacial del hábitat potencial de la trufa negra (Tuber melanosporum Vittad.) en la provincia de Huesca (España)

El cultivo de la trufa negra ( Tuber melanosporum Vittad.) es especialmente complicado por las exigencias ambientales que requiere. En el presente trabajo se propone un modelo de distribución de su hábitat en la provincia de Huesca (España). Para ello se usan factores condicionantes y limitantes de la presencia de la especie en el territorio en función de experiencias previas, y apoyado por un amplio conjunto de muestras de suelo tomadas directamente en campo. Se consideraron todas aquellas variables ambientales capaces de explicar la presencia/ausencia de la especie en el territorio. Dichas variables se clasifican en tres grupos según su naturaleza: climático, topográfico y edáfico. Se utilizaron Sistemas de Información Geográfica para integrar todas las variables ambientales en su dimensión espacial, y a través de un modelo de decisión de evaluación multicriterio se ponderaron para obtener una cartografía de aptitud. La asignación de los pesos relativos a cada variable se realizó en función de la importancia que tienen para el desarrollo de la especie, las experiencias similares en otros lugares, y en relación al área de estudio trabajada. La combinación de las variables ambientales que condicionan y limitan la aparición de la trufa negra en el territorio, en su dimensión espacial, dio como resultado una cartografía de distribución del hábitat potencial de la especie que muestra, a diferentes niveles, cuáles son las zonas con mayor o menor capacidad de producción de trufa negra. Los resultados muestran que un 2, 75% de la superficie de toda la provincia tiene una aptitud óptima para el desarrollo de la especie en función de su hábitat potencial, cifra que se reduce hasta 1, 62% cuando se trata de zonas potencialmente cultivables. El mapa fue validado con las presencias de trufa conocidas disponibles para el área de estudio. Black truffle (Tuber melanosporum Vittad.) cultivation is especially complicated by their environmental requirements. We propose in this paper a distribution model of habitat for Huesca province (Spain). We used conditioning and restricting factors to the presence of the species in territory based on previous ex-Gonperiences, and supported by a broad collection of field samples. Environmental variables can explain the presence/absence of the species in the study area. These variables are classified in three groups according to their nature: climatic, topographic and edaphic. We integrated in a GIS all parameters to unify spatial resolution, and by a multi-criteria decision model weighted them to obtain suitability areas. The weights allocation were assigned in function of their importance to black truffle presence and previous experiences. The combination of environmental variables that are conditioning and restricting the presence of black truffle in territory, generates a cartography of potential habitat distribution at different levels These levels are areas with more or less production ability of black truffle. Results show that 2.75% of province has an optimal aptitude to species development, this number is reduced to 1.62% in potential cultivation. Map was validated with available presences of known truffle locations in study area

Towards a new quality-controlled daily climate dataset for the Pyrenees, 1950-2015

Póster presentado en: EMS Annual Meeting: European Conference for Applied Meteorology and Climatology celebrado del 4 al 8 de septiembre de 2017 en Dublin, IrlandaPrevious works using lower-density datasets addressed warming rates with slight differences depending on the season and diffuse trends for precipitation. New and more accurate results in spatio-temporal variations of these climate variables are expected on behalf the development of the CLIM’PY project, which aims to: i) detect past trends with instrumental data and, ii) estimate future behaviours in climatic variables based on projected scenarios. Temperature, precipitation and snow cover in the Pyrenees will be analysed within the framework of the project. In this communication, we present the methodology we will follow to conduct the quality control analysis of daily temperature and precipitation, which will include 673 stations of Spain, France and Andorra, covering the period 1950-2015

Observed climatic trends in the Pyrenees (1950-2015)

Póster presentado en: EGU General Assembly 2019 celebrada del 7 al 12 de abril en Viena, Austria

New daily quality-controlled data base for the Pyrenees (1950-2015)

Presentación realizada para el: EMS Annual Meeting - European Conference for Applied Meteorology and Climatology 2018, celebrado en Budapest del 3 al 7 de septiembre de 2018