Jose A. Guijarro

• PhD
• Retired from the Spanish State Meteorological Agency (AEMET)

In this work, we present results of the development of an observation‐based gridded climate dataset (ClimUAd), which covers the territory of Ukraine for the period of 1946–2020. The spatial resolution of the developed data is 0.1° × 0.1° (approximately 10 km in both longitude and latitude directions), with a 1‐day time step. Four essential climate...

Strong winds have evident impacts on the environment and the society. It can affect the dispersion of air pollutants, land erosion, and damage buildings, representing a severe hazard to people and properties. However, the changes and variabilities of extreme winds are still largely unknown, especially in global high-elevation regions, e.g., the Tib...

Strong winds have evident impacts on the environment and the society. It can affect the dispersion of air pollutants, land erosion, damage buildings, representing a severe hazard to people and properties. However, the changes and variabilities of extreme winds are still largely unknown, especially in global high-elevation regions, e.g., the Tibetan...

Calculation of the new climatological standard normals for the period 1991–2020 was a motivation to carry out the homogenization of the required climatic variables in the Spanish Meteorological Agency (AEMET). The national observation network has undergone changes along its history that often introduce non-climatic interferences to the series. On t...

As near-surface wind speed plays a role in regulating surface evaporation and thus the hydrological cycle, it is crucial to explore its spatio-temporal characteristics. However, in-situ measurements are scarce over the Tibetan Plateau, limiting the understanding of wind speed climate across this high-elevation region. This study explores the climat...

Measurements in seven sites in the Campus of the University of the Balearic Islands (UIB; Mallorca, Spain) during an experimental campaign to study the contribution of local surface heterogeneities on the surface energy budget at one point have been used to characterize the differences in extreme daily temperatures between the sites during a summer...

In this paper we present the results of quality control and homogenization procedures applied to long time series of daily atmospheric precipitation sums (Rr) and daily mean (Tm), maximum (Tx) and minimum (Tn) air temperature collected in Ukraine. The daily data from 178 meteorological stations covering the period of 1946–2020 were analysed. In ord...

RESUMEN Hacia comienzos de 2021 aparecieron dos mensajes contradictorios en sendos medios de Baleares, afirmando uno de ellos que el archipiélago lideraba el calentamiento climático en España mientras que el otro anunciaba que Baleares era una de las regiones donde menos había subido la temperatura desde 1961. Como ambos medios decían basarse en tr...

The homogenization of climate observational series is a needed process before undertaking confidently any study of their internal variability, since changes in the observation methods or in the surroundings of the observatories, for instance, can introduce biases in the data of the same order of magnitude than the underlying climate variations and...

This research presents a case study of the biases and discontinuities that were introduced in observed long-term mean wind-speed and gust data-series due to anemometer changes in a meteorological station in northern Spain, operated by the Spanish State Meteorological Agency: San Sebastian-Igueldo. Field and wind-tunnel experiments with predefined c...

La présente étude porte sur l'homogénéisation des précipitations mensuelles d'une base de données collectée pour l'ensemble de la région Fès Meknès et sur la régionalisation spatio-temporelle l'analyse des tendances des précipitations annuelles. Les méthodes déployées utilisent l'outil CLIMATOL, l'analyse en composante principales avec rotation de...

This study analyses quality controlled and homogenized near-surface wind speed series (SWS) at 87 meteorological stations distributed across Spain and Portugal for 1961–2019. Multidecadal variability analysis of both mean and gusts SWS confirms for the first time in the region the cessation of the stilling (decline of SWS) and a possible weak rever...

As near-surface wind speed plays a key role in regulating surface evaporation and thus the hydrological cycle, it is crucial to explore its spatio-temporal characteristics. However, in-situ measurements are scarce over the Tibetan Plateau, limiting the understanding of wind speed climate across this high-elevation region. This study explores the cl...

This research presents a case study of the biases and discontinuities that were introduced in observed long-term mean wind-speed and gust data-series due to anemometer changes in a meteorological station in northern Spain, operated by the Spanish State Meteorological Agency: San Sebastian-Igueldo. Field and wind-tunnel experiments with predefined c...

Eastern Texas straddles a precipitation zone that transitions from semi-arid grasslands to the humid, rainy conditions of the northern Gulf Coast. While several studies have quantified the changing magnitude and frequency of daily extreme events, the paucity of hourly datasets have limited insight into how the growing proportion of rainfall exceedi...

Using observations and model simulations from the 5th and 6th phases of the Coupled Model Intercomparison Project (CMIP5 and CMIP6, respectively), this study evaluated changes in monthly, seasonal, and annual precipitation over Bolivia from 1950 to 2019. Results demonstrate that observed precipitation is characterized by strong interannual and deca...

Using observations and model simulations from the 5th and 6th phases of the Coupled Model Intercomparison Project (CMIP5 and CMIP6, respectively), this study evaluated changes in monthly, seasonal, and annual precipitation over Bolivia from 1950 to 2019. Results demonstrate that observed precipitation is characterized by strong interannual and deca...

Homogenised climatological series and gridded data are the basis for climate monitoring and climate change detection. Considering this, monthly mean temperatures from 122 Croatian stations were homogenised, and high-resolution monthly gridded data were developed for the 1981–2018 period. Homogenisation needs to be performed on stations from the sam...

Most studies on wind variability have deepened into the stilling vs. reversal phenomena at global to regional scales, while the long-term changes in local-scale winds such as sea-breezes (SB) represent a gap of knowledge in climate research. The state-of-the-art of the wind variability studies suggests a hypothetical reinforcement of SB at coastal...

La présente étude porte sur l'homogénéisation des précipitations mensuelles d'une base de données collectée pour l'ensemble de la région Fès Meknès et sur la régionalisation spatio-temporelle l'analyse des tendances des précipitations annuelles. Les méthodes déployées utilisent l'outil CLIMATOL, l'analyse en composante principales avec rotation de...

High quality and long-term precipitation data are required to study the variability and trends of rainfall and the impact of climate change. In developing countries like Morocco, the quality of climate data collected from various weather stations faces numerous obstacles. This paper presents methods for collecting, correcting, reconstructing, and h...

Great attention has been paid to the long-term decline in terrestrial near-surface wind speed (SWS) in China. However, how the SWS varies with regions and seasons and what modulates these changes remain unclear. Based on quality-controlled and homogenized terrestrial SWS data from 596 stations, the covarying SWS patterns during the Asian Summer Mon...

The northern U.S. Gulf Coast is among the wettest regions in the contiguous United States, with a transition zone from humid to semi-arid climates occurring between the western Gulf Coast and the 100th meridian. As anthropogenic warming induces more frequent extreme wetting events of greater magnitude, a larger proportion of rainfall runs off unsat...

Wind extremes cause many environmental and natural hazard related problems globally, particularly in heavily populated metropolitan areas. However, the underlying causes of maximum wind speed variability in urbanized regions remain largely unknown. Here, we investigated how rapid urbanization in the Yangtze River Delta (YRD), China, impacted daily...

Most studies on wind variability have deepen into the stilling vs. reversal phenomena at global to regional scales, while the long-term changes in local-scale winds such as sea-breezes (SB) represent a gap of knowledge in climate research. The state-of-the-art of the wind variability studies suggests a hypothetical reinforcement of SB at coastal st...

This study analyses quality controlled and homogenized near-surface wind speed series (SWS) at 87 meteorological stations distributed across Spain and Portugal for 1961–2019. Multidecadal variability analysis of both mean and gusts SWS confirms for the first time in the region the cessation of the stilling (decline of SWS) and a possible weak rever...

This study analyses for the first time the break in the stilling detected by previous research around 2010, with focus in Sweden using homogenized near‐surface mean and gust wind speed observations for 1997–2019. During the recent past two decades, both mean and gust wind magnitude and frequency (exceeding the 90th percentile) underwent nonlinear c...

A decline in mean near‐surface (10 m) wind speed has been widely reported for many land regions over recent decades, yet the underlying cause(s) remains uncertain. This study investigates changes in near‐surface wind speed over northern China from 1961 to 2016, and analyzes the associated physical mechanisms using station observations, reanalysis p...

An observed daily peak wind gusts (DPWG) dataset over Scandinavia, consisting of time series from 127 meteorological stations across Finland, Norway and Sweden, has been created. This dataset provides high‐quality and homogenized near‐surface DPWG series for Scandinavia, spanning the longest available time period (1996–2016). The aim of this study...

Reliable secular time series of essential climatic variables are a fundamental element for the assessment of vulnerability, impact and adaptation to climate change. Here, we implement a readily portable procedure for building an upgradable long‐term homogeneous climate dataset using monthly and daily observations of temperature and precipitation ov...

The Mid-Atlantic region of the USA has experienced increasing annual precipitation amounts in recent decades, along with more frequent extreme events of greater magnitude. Unlike many US regions that have suffered increasing drought conditions from higher evapotranspiration demand, positive trends in the Mid-Atlantic accumulated precipitation are g...

Wind gusts represent one of the main natural hazards due to their increasing socioeconomic and environmental impacts on, as examples: human safety; maritime-terrestrial-aviation activities; engineering and insurance applications; and energy production. However, the existing scientific studies focused on observed wind gusts are relatively few compar...

The aim of time series homogenization is to remove non-climatic effects, such as changes in station location, instrumentation, observation practices, etc., from observed data. Statistical homogenization usually reduces the non-climatic effects, but does not remove them completely. In the Spanish MULTITEST project, the efficiencies of automatic homo...

Northern Chile is a region characterised by an extremely dry climate; however, there is a brief rainy season from December to March (austral summer), mainly above 3000 m a.s.l. It is interesting to consider where the humid air masses that generate such rain come from. For this purpose, daily precipitation data from 161 meteorological stations locat...

The present study investigated the uncertainty associated with Climatol's adjustment algorithm applied to daily minimum and maximum air temperature. The uncertainty quantification was performed based on several numerical experiments and the benchmark data that were created in the framework of the INDECIS project. Using a complex approach, the uncer...

Northern Chile is one of the most arid regions in the world, with precipitation mainly occurring during austral summer, between December and April 1966-2015. The aim of this study is to classify the main weather regimes derived from sea level pressure, surface wind speed, 500 or 250 hPa geopotential heights, in order to measure their influence on p...

We assess the performance of different break detection methods on three sets of benchmark datasets, each consisting of 120 daily time series of integrated water vapor differences. These differences are generated from the Global Positioning System (GPS) measurements at 120 sites worldwide, and the numerical weather prediction reanalysis (ERA‐Interim...

Long‐term and high quality observed climate data are required to analyse with reduced uncertainty temporal and spatial climate variability. The aim of this work is the quality control, the reconstruction and homogenization of monthly precipitation observed in semi‐arid basins within Souss‐Massa region in North Africa during the period 1933–2010. Da...

A dense monthly precipitation dataset of Ireland and Northern Ireland was homogenized with several modern homogenization methods. The efficiency of these homogenizations was tested by examining the similarity of homogenization results both in the real data homogenization and in the homogenization of a simulated dataset. The analysis of homogenizati...

Time series homogenization for 299 of the available precipitation records for the island of Ireland (IENet) was performed. Four modern relative homogenization methods, that is, HOMER, ACMANT, CLIMATOL and AHOPS were applied to this network of station series where contiguous intact monthly records range from 30 to 70 years within the base period 194...

Assessing change in daily maximum wind speed and its likely causes is crucial for many applications such as wind power generation and wind disaster risk governance. Multi-decadal variability of observed near-surface daily maximum wind speed (DMWS) from 778 stations over China is analyzed for 1975 – 2016. A robust homogenization protocol using Clima...

Assessing change in daily maximum wind speed and its likely causes is crucial for many applications such as wind power generation and wind disaster risk governance. Multi-decadal variability of observed near-surface daily maximum wind speed (DMWS) from 778 stations over China is analyzed for 1975 – 2016. A robust homogenization protocol using Clima...

There has been growing interest in recent years in the use of homogeneously reprocessed ground-based GNSS, VLBI, and DORIS measurements for climate applications. Existing datasets are reviewed and the sensitivity of tropospheric estimates to the processing details is discussed. The uncertainty in the derived IWV estimates and linear trends is aroun...

Northern Chile is one of the most arid regions in the world, with precipitation mainly occurring during austral summer, between December and April 1966–2015. The aim of this study is to classify the main weather regimes derived from sea level pressure, surface wind speed, 500 or 250 hPa geopotential heights, in order to measure their influence on p...

Daily and sub‐daily homogenization of climate variables have been intensively investigated in the last decades, but to the best of our knowledge, this is the first study on homogenization of hourly temperature in Romania. This paper describes the creation of a homogenized hourly air temperature data set at a country scale by combining data from fou...

A new high‐resolution (5 km) gridded daily precipitation dataset for Tunisia between 1979 and 2015 is introduced. This product combines 960 rain gauges with the SAFRAN analysis to produce the precipitation gridded data. A validation approach on two different datasets reveals that the SAFRAN analysis outperforms other standard interpolation methods...

Northern Chile is one of the most arid regions in the world, as it includes the Atacama Desert. At high elevations, most precipitation is observed only during a short period of the year, from December until March. This renders water availability a major concern for policymakers. Accumulated rainfall varies considerably from one year to another, and...

Studies which evaluate the impact of wind-related hazards need to have access to reliable and homogeneous measurements. Unfortunately, observed wind series can be affected by several non-climatic artifacts, which may introduce inhomogeneities that mislead the study of climate trends and multi-decadal variability. This study compares different homog...

Daily Peak Wind Gust (DPWG) time series are important for the evaluation of wind-related hazard risks to different socioeconomic and environmental sectors. Yet wind time series analyses can be impacted by several artefacts, such as anemometer changes and site location changes, both temporally and spatially, that may introduce inhomogeneities that m...

The Wind erosion in arid and semi-arid areas is an important global environmental issue, and changes in wind speed trends over time play a key role in wind erosion dynamics. In a warming climate, scientists have recently observed a widespread decline in wind speed, termed "stilling". Here, we apply the Revised Wind Erosion Equation Model (RWEQ) to...

Wind erosion in arid and semi-arid areas is an important global environmental issue, and changes in wind speed trends over time play a key role in wind erosion dynamics. In a warming climate, scientists have recently observed a widespread decline in wind speed, termed “stilling”. Here, we apply the Revised Wind Erosion Equation Model (RWEQ) to simu...

Daily Peak Wind Gust (DPWG) time series are important for the evaluation of wind‐related hazard risks to different socioeconomic and environmental sectors. Yet, wind time series analyses can be impacted by several artefacts, both temporally and spatially, which may introduce inhomogeneities that mislead the study of their decadal variability and tr...

According to the Intergovernmental Panel on Climate Change (IPCC), Northern Chile will be one of the most affected territories by changes in the atmospheric dynamics in next years. These climate change effects will be noticed in several ways, and temperatures will be one of the most sensitive variables to these changes, and with high importance bec...

Draft guidance on the homogenisation of climate station data of the World Meteorological Organisation.

This study analyzes the variability of winter haze days and visibility in the Beijing-Tianjin-Hebei (BTH) region in relation to wind speed changes in the lower troposphere and emissions for 1961-2014. Daily surface meteorological data, NCEP/NCAR atmospheric reanalysis data, and fossil fuel emission data are used in this research. The results reveal...

Daily Peak Wind Gusts (DPWG) time-series are valuable data for the evaluation of wind related hazard risks to different socioeconomic and environmental sectors. Yet wind time-series analyses can be impacted by several artefacts, both temporally and spatially, that may introduce inhomogeneities that mislead the studies of their decadal variability a...

Twenty-first century surface air temperatures keep rising globally, driving changes in regional extreme weather and climate events [1]. These hazards are becoming more frequent and severe and are impacting humans and ecosystems [2]. Due to their complex origins, extreme events are challenging to predict. Windstorms and extreme wind events cause mor...

Northern Chile is one of the most arid regions in the world, as includes the Atacama Desert, but in high altitudes, precipitation is recorded in a very constricted season every year. This makes that water availability is one of the main concerns for policymakers. Accumulated rainfall presents very high differences from one year to another, and this...

This study analyzes the variability of winter haze days and visibility in the Beijing-Tianjin-Hebei (BTH) region, in relation to the regional average wind speed changes in the lower troposphere and emissions for 1961–2014. Winter mean surface meteorological data, NCEP/NCAR atmospheric reanalysis data, and fossil fuel emission data are used. The res...

Detecting breaks in tropospheric data is indispensable, since these breaks directly affect the trend estimates from Zenith Total Delay (ZTD) series or Integrated Water Vapor (IWV) records. Various algorithms have been already employed to report the exact epochs of break points during the entire time span of ZTD or IWV series. This procedure is know...

Supplementary material for the journal article "East Africa Rainfall Trends and Variability 1983–2015 Using Three Long-Term Satellite Products" by Cattani et al., 2018

Daily time series from the Climate Prediction Center (CPC) Africa Rainfall Climatology version 2.0 (ARC2), Climate Hazards Group InfraRed Precipitation with Stations (CHIRPS) and Tropical Applications of Meteorology using SATellite (TAMSAT) African Rainfall Climatology And Time series version 2 (TARCAT) high-resolution long-term satellite rainfall...

This manual is a complement to the standard documentation of the R package "climatol", explaining the main procedures to homogenize climate series and to obtain statistical summaries and grids from the adjusted and completed series.

During the last decade scientists have reported a terrestrial slowdown in wind speed across the world. This weakening in wind speed has been recently termed the “stilling” phenomenon, with a worldwide average trend of -0.140 m s-1 decade-1 reported since the 1960s. The precise causes of this “stilling” remain largely uncertain and have been hypothe...

Daily Peak Wind Gusts (DPWG) time-series are valuable data for evaluation of wind related hazard risk to the population and different economic sectors. Yet wind time-series are prone to be affected by inhomogeneities temporally and spatially (e.g. through change of instruments at a site compared to surrounding sites) that may mislead the studies of...

As part of the COST Action HOME a dataset has been generated that will serve as a benchmark for homogenisation algorithms. Members of the Action and third parties have been invited and are still welcome to homogenise this dataset. The results of this exercise was analysed to obtain recommendations for a standard homogenisation procedure and are des...

We analyse recent trends and variability of observed near-surface wind speed from 19 stations across Saudi Arabia (SA) for 1978-2013. The raw wind speed data set was subject to a robust homogenization protocol, and the stations were then classified under three categories: (1) coast, (2) inland and (3) mountain stations. The results reveal a statist...

Using clustering analysis for the SLP field of the ERA Interim reanalysis between 1979 and 2016, five synoptic pressure patterns have been obtained for Drake area and Antarctic Peninsula (AP) region (45°S 75°S 20°W 120°W) and the resulting daily series has been made available to the scientific community. The five patterns have been named according...

AbstractObservations are the foundation for understanding the climate system. Yet, currently available land meteorological data are highly fractured into various global, regional and national holdings for different variables and timescales, from a variety of sources, and in a mixture of formats. Added to this, many data are still inaccessible for a...

Extreme wind hazards have a substantial societal and environmental impact. Due to their complex origins, there are great knowledge gaps about their variations and the associated mechanisms, which makes the prediction challenging. Specifically there is a urgent need to evaluate numerical models’ capability in simulate extreme wind conditions. This s...

A proper homogenization of tropospheric dataset is indispensable, as the parameters of deterministic part, e.g. trend will be influenced by undetected breaks. Different groups have already used different methods and obtained different estimates - the truth is not known. A synthetic benchmark dataset is a proper way to quantify results given by vari...

This work presents a catalog of daily precipitation fields in the Balearic Islands created with data from AEMET (State Meteorological Agency) assistant observations, including records from 1912. The original digital daily data file has been interpolated onto a regular 100 m-resolution grid (namely PREGRIDBAL), defined with the aim of becoming a val...

A synthetic benchmark dataset of Integrated Water Vapour (IWV) was created within the activity of “Data homogenisation” of sub-working group WG3 of COST ES1206 Action. The benchmark dataset was created basing on the analysis of IWV differences retrieved by Global Positioning System (GPS) International GNSS Service (IGS) stations using European Cent...

Within the COST Action ES1206 “Advanced Global Navigation Satellite Systems tropospheric products for monitoring severe weather events and climate” (GNSS4SWEC), there was a clear interest and need to homogenize a worldwide Integrated Water Vapour (IWV) dataset retrieved with Global Positioning System (GPS), by correcting (artificial) break points d...