Top PDF The state of climate in NW Iberia

The state of climate in NW Iberia

The state of climate in NW Iberia

Changes in the circulation of the atmosphere and underlying oceans are also part of climate change. It is worth noting that the present study region (northwest IP) lies within the mid-latitude belt of the westerlies. Important for the climate of this region is the prevailing westerly circulation that brings the oceanic air masses inland. Stronger advection from the west brings milder and wetter weather and stronger winds, especially in autumn and winter. Weaker and blocked westerly circulation patterns lead to generally colder and drier winters and hotter and drier summers. A general picture of the atmospheric circulation of the North Atlantic includes a poleward shift in storm-track loca- tion (Wang et al. 2006), although long-term changes in extratropical storm activity becomes dif ficult to discern because of the noise present in the observations (IPCC 2007). Blocking activity seems to be less intense over the North Atlantic region throughout the most recent decades, with statistically significant decreases in events and duration (Barriopedro et al. 2006), while cut-off lows, as the other main feature of the circula- tion, appear to have an inter-annual variability (Nieto et al. 2005). In this general context, the IP climate is strongly influenced by its position within the northern mid-latitudes, and its location between the Atlantic Ocean and the Mediterranean Sea, as well as the exis- tence of 2 important mechanisms of atmospheric mois- ture and instability — the precipitation regime in the northern and western edges of the IP is strongly affected by the location of the Atlantic storm tracks, whereas the interior and the eastern half of the IP is affected by both large-scale synoptic systems from the Atlantic and convective precipitation originating over the Mediterranean (Trigo et al. 1999, Trigo & Da - Camara 2000, Castro et al. 2005). The orography of the IP has a strong influence on the way that baroclinic perturbations and convective systems affect the local climate. Furthermore, the IP has 2 further character - istics that influence precipitation variability across the region, namely: (1) its location toward the southern margin of the Atlantic westerly belt (Zhu & Newell 1998), the main large scale feature providing moisture at mid-latitudes, and (2) its location in southwestern Europe, which results in the variability of precipitation in some parts of the IP reflecting the connection to the large-scale North Atlantic atmo spheric circulation (von Storch et al. 1993, Serrano et al. 1999, Trigo & Palutikof 2001).
Mostrar mais

36 Ler mais

Köppen, Thornthwaite and Camargo climate classifications for climatic zoning in the State of Paraná, Brazil

Köppen, Thornthwaite and Camargo climate classifications for climatic zoning in the State of Paraná, Brazil

Data from European Center for Medium-Range Weather Forecast (ECMWF) models are widely used worldwide because they have great advantages over data from weather stations in terms of speed in acquiring (in near real time) new data, providing coverage for the entire surface of the earth and having an absence of missing values. The literature contains several works that demonstrate a high correlation between the ECMWF model and surface data. For example, Moraes et al. (2012) calibrated the ECMWF data from surface data in the State of São Paulo and observed a high correlation.
Mostrar mais

13 Ler mais

Climate change and future scenarios for palisade grass production in the state of São Paulo, Brazil

Climate change and future scenarios for palisade grass production in the state of São Paulo, Brazil

measures. Standard error of the mean was calculated as a measure of dispersion. Time series of annual forage accumulation were created using data from 1963 to 2070, excluding 2010, 2011, 2012, 2041, and 2042. Analyses of variance of the annual forage accumulation rate (dependent variable) were performed in accordance with the years (independent variable) and, when significant, the angular coefficient, intercept, and coefficient of determination were tested. These analyses were performed using the R software, version 12.15.0 (R Foundation for Statistical Computing, Vienna, Austria). Maps were obtained by the natural neighbor method, from the spatial interpolation of the average data with the ArcGIS Software version 10.1 (Esri Headquarters, Redlands, CA, USA), using the spatial analyst tools / interpolation / natural neighbor tool.
Mostrar mais

9 Ler mais

Review article of the current state of glaciers in the tropical Andes: a multi-century perspective on glacier evolution and climate change

Review article of the current state of glaciers in the tropical Andes: a multi-century perspective on glacier evolution and climate change

Fig. 1. (a) Glaciers monitored in the tropical Andes. Glaciers with countinous mass balance series (small red hexagons) are labelled. For these glaciers length (yellow cube) and area (blue circle) records also exist. The large red hexagon depicts a sample of 21 glaciers in the Cordillera Real, Bolivia, for which mass balance reconstructions are available from 1963 to 2006 (Soruco et al., 2009a). Other glaciers whose changes in length and/or in area are moni- tored are numbered. “MB initiated” indicates glaciers with mass balance measurements starting in 2008 (Incachiriasca), 2009 (Coropuna) and 2010 (Quisoquipinia). (b) General atmospheric circulation over South America. The dotted frame shows the extent of the precipitation maps in Fig. 1c and d. (c) and (d) Mean hourly precipitation intensity (mm hr −1 ) in January (c) and July
Mostrar mais

60 Ler mais

The Upper Paleolithic Rock Art of Iberia

The Upper Paleolithic Rock Art of Iberia

Finally, recent years have seen the attractive, color photo-laden, trade-market publications of Altamira (Saura and Beltr´an, 1998 ) and of Ekain and Altxerri (Altuna, 1997 ). In response to concern for conservation, coupled with a need to foment tourism and to satisfy the growing public demand to see cave art, replicas of Altamira and Ekain have been built—the former as part of an ultra-modern mu- seum focused on Cantabrian cave art in its paleoanthropological context, located adjacent to the real cave of Altamira. Few Iberian rock art sites are currently open to the public and those that are still open (e.g., Candamo, Bux´u, Tito Bustillo, Pindal, Chuf´ın, Castillo, Monedas, Hornos de la Pe˜na, Pendo, Covalanas, Santimami˜ne, Pileta, Nerja, Ardales, Casares, several Cˆoa loci) have increasingly strict limi- tations on visitor numbers. Excellent interpretive centers have been constructed in association with both open and closed sites (e.g., Fuente del Trucho, Ardales, Cˆoa). One of the ironies of the present situation is that just as the broad public (in both Europe and USA) is becoming aware of, fascinated by, and desirous of seeing Paleolithic rock art, archeologists (sometimes in opposition to local authorities, sometimes in collaboration with them) are coming to realize just how fragile this resource is and how restrictive we must be to protect it, if—having survived for 10–30 millennia so far—it is to survive the present century. The present article is a first attempt to succinctly synthesize the current state of our knowledge of the Paleolithic rock art of Spain and Portugal for a readership of English-speaking archeologists. However, it should be noted that current syntheses on a Peninsular scale are lacking even in Spanish or Portuguese, although an “atlas” is currently in preparation (Fortea, n.d.).
Mostrar mais

71 Ler mais

Solar energy potential in a changing climate : Iberia and Azores assessment combining dynamical and statistical downscaling methods

Solar energy potential in a changing climate : Iberia and Azores assessment combining dynamical and statistical downscaling methods

The systematic biases of the simulated solar radiation characterized above are here corrected with linear regression (LR) and quantile mapping (QM). The comparison between these methods allows us to select the most appropriate to obtain a solar resource map for the Iberian Peninsula in present climate. Figure 4.3 shows the cross-validated relative BIAS, the normalized standard deviation and the skill score for both methods. The BIAS of the WRF solar radiation data is reduced to negligible values (around 0%) by LR (Fig.4.3b-c). The QM however, does not reach such low values but it also reduces significantly the BIAS compared to the uncorrected WRF solar radiation data. The maximum BIAS value obtained after QM correction is approximately 9% but almost 80% of the individual stations datasets attain BIAS values that are below 5%. Regardless the MOS method used, the MAPE was also reduced from 11-41% to 10-32.5 % (Appendix A, Fig. A2a-b) and the relative RMSE from 15- 55% to 15-45% (Appendix A, Fig. A2d-e). The skill score statistic (S) though (Fig.4.3 g-h) gives a lead to the QM method over the LR which is confirmed by the normalized frequencies of the error values (Fig.4.3i). Almost 70% of the locations analysed with QM method attained skill scores over 85%. The LR results vary in its majority between 75 and 82%. Another advantage of the QM correction over LR is that QM achieves closer results to perfect variance ratios (Fig.4.3f), whereas LR shows an underestimation (Fig. 4.3e), which is a basic property of non-randomized LR because it only captures the explained variance. The correlation coefficients (not shown) for the LR method are by construction identical to those of the raw WRF output, and are also not changed by the QM.
Mostrar mais

142 Ler mais

Parasitic profile of traction equids in the semi-arid climate of Paraíba State, Northeastern, Brazil

Parasitic profile of traction equids in the semi-arid climate of Paraíba State, Northeastern, Brazil

The mean (±SD) EPG of the traction equids was 1143(±1853). The donkeys possessed a statistically lower mean EPG (p ≤ 0.05) as compared to the other species at 807 (± 770), whereas the mule EPG average was 1571 (± 2682) and the horses was 1050 (± 800). On classifying by category, 35% (34/96) of the animals were classified as having low-level infection (<500), 28% (27/96) as medium (500-1000), and 37% (35/96) as high (>1000). The donkeys possessed the highest percentage of positive fecal examinations but the lowest level of parasitic disease, confirming the resistance of the species. Chitra et al. (2011) stated that, although donkeys are also known in India for their robustness, they are the species most vulnerable to parasitic infection.
Mostrar mais

5 Ler mais

Does the reproductive season account for more records of birds in a marked seasonal climate landscape in the state of São Paulo, Brazil?

Does the reproductive season account for more records of birds in a marked seasonal climate landscape in the state of São Paulo, Brazil?

over open habitats. I walked slowly at constant speed (5 km/h) and recorded every bird seen or heard within an estimated 100 m of the transect center line. In or- der to avoid counting the same bird twice, one species was never registered after if it was heard again in front of the observer unless it was undoubtedly another individual. Observations were made with binoculars (8 × 42) and vocalizations were tape recorded with a built-in microphone cassette recorder. The same di- rection of travel was followed on both routes, which were sampled twice during the day, once during the mornings and once during the afternoons. Transects comprised the same type of forest (cerradão wood- land), although I spent 80% of transect counting in open habitats. Routes were sampled every 15 days in September and December 2005 and from January- November 2006. I started all transects 10 min before sunrise and continued until midday, except for a few occasions when I interrupted them at 10:00.
Mostrar mais

8 Ler mais

Climate, soil and tree flora relationships in forests in the state of São Paulo, southeastern Brasil

Climate, soil and tree flora relationships in forests in the state of São Paulo, southeastern Brasil

The family similarity pattern shown by figure 3 is not likely to have any relation to the climate or to altitudinal variations or to the average frequency of frost. Moreover, the high values of similarity in figure 3 may be interpreted as an indication of only one family block for all forests compared. This situation implies in that the recognition of family groups is rather artificial, and the attempt to relate them to abiotic feature is quite inappropriate. However, bearing in mind all these limitations, it is possible to recognize some coherences. Anhembi (group a) occurs on a soil with a very sandy (over 90%) texture, detaching from all other samples at the 42% similarity level (figure 3) which do not show a so high sand content. This separation is coherent with the species similarity pattern opposing groups 7 and 8 of figure 2. By consulting the primary binary matrix it is possible to point out Magnoliaceae, Polygonaceae and Violaceae as examples of families occurring preferably on Quartz Sand soil.
Mostrar mais

9 Ler mais

Reference Evapotranspiration Estimation in Climate Change Scenarios for Rio Verde in the State of Goiás, Brazil

Reference Evapotranspiration Estimation in Climate Change Scenarios for Rio Verde in the State of Goiás, Brazil

methods, their performance was evaluated through statistical indices in four future climate scenarios. The projections originated from two emission scenarios based on the HadGEM2-ES global climate model with medium (2040-2069) and long (2070-2099) term scenarios. The results presented that the Radiation and Turc methods are currently—and can be under the predicted conditions of future climate scenarios—the best options for estimation of ET 0 in Rio Verde, when

5 Ler mais

On the state-dependency of the equilibrium climate sensitivity during the last 5 million years

On the state-dependency of the equilibrium climate sensitivity during the last 5 million years

system with respect to previous studies. Third, previously (e.g. van de Wal et al., 2011) polar amplification was assumed to be constant over time. However, climate models (Haywood et al., 2013) indicate that during the Pliocene, when less ice was present on the Northern Hemisphere, the temperature perturbations were more uniformly spread over all latitudes. We incorporate this changing polar amplification in our global tem-

51 Ler mais

Incorporating climate trends in the stochastic modeling of extreme minimum air temperature series of Campinas, state of São Paulo, Brazil

Incorporating climate trends in the stochastic modeling of extreme minimum air temperature series of Campinas, state of São Paulo, Brazil

As indicated by El Adlouni et al. (2007), the most general model is frequently the best to represent the data sample under evaluation. However, El Adlouni et al. (2007) also indicate that according to the parsimony principle when the differences between two models Model i and Model j (in which; Model i ⊂ Model j if j>i) are not significant, it is better to use the simplest one (Model i ). The uncertainty in quantile estimation tends to increase as the number of parameters to be estimated increases. In this view, model 1 can be seen as a particular case of model 2. At the same time, these both models can be seen as particular cases of model 3. These three models are, indeed, particular cases of model 4. According to Coles (2001), the Λ* algorithm can also be applied to compare the validity of a more gen- eral model against a particular case (p-values less than or equal to 0.05 were seen as an evidence that the most gen- eral model is better than the particular one).
Mostrar mais

6 Ler mais

Climate change scenarios and their impact on the water balance of sugarcane production areas in the State of São Paulo, Brazil

Climate change scenarios and their impact on the water balance of sugarcane production areas in the State of São Paulo, Brazil

From the results obtained in this study, we concluded that climate change, independently of the scenario considered, will impose an increase in potential and actual evapotranspirations, resulting in higher water deficits in all regions. This will be of great concern for sugarcane growers since it can reduce the yields of rainfed crops. On the other hand, water surplus will be reduced, which will have impact on groundwater and, consequently, on the water reservoirs levels, making irrigation very restrict and expansive. The changes in rainfall, positive (+10%) or negative (-10%), will have less influence on the water availability of the regions than the changes in temperature and, consequently, in evapotranspiration. In relation to the method of analysis, the use of historical data, year by year, allowed to identify that the impacts of climate change on water availability will be even worse than predicted by the studies which took into account only normal average data.
Mostrar mais

11 Ler mais

Climate change, in the framework of the constructal law

Climate change, in the framework of the constructal law

The work described in Bejan and Reis (2005) and Reis and Bejan (2006) was based on steady-state and quasisteady (periodic, diurnal) models. Its success recommends its application to elucidating what is perhaps the biggest issue in geophysics today: climate change, its time scale, and how to make its treatment and understanding ac- cessible with pencil and paper, or chalk on the blackboard. In this article we unveil the 15

30 Ler mais

AGROCLIMATIC ZONING FOR EUCALYPTUS IN THE STATE OF PARANÁ AND THE NEW SCENARIOS DEFINED BY GLOBAL CLIMATE CHANGE

AGROCLIMATIC ZONING FOR EUCALYPTUS IN THE STATE OF PARANÁ AND THE NEW SCENARIOS DEFINED BY GLOBAL CLIMATE CHANGE

The coastal region of Paraná, which is also in white, is unsuitable for eucalyptus due to high temperature, precipitation and humidity (WREGE et al., 2011). For this reason, the commercial plantation of eucalyptus is not feasible in this region (even when considering the future scenarios) due to the high probability of occurrence of fungal diseases that could benefit from the excess moisture, such as rust, caused by the fungus Puccinia psidii (BORA et al. Al., 2016).
Mostrar mais

13 Ler mais

IN THE STATE OF SÃO PAULO

IN THE STATE OF SÃO PAULO

temperature changes. Nevertheless, significant differences were observed in MB-N and MB-C contents among the sampling periods for all forests except the PETAR NF. This finding could indicate that the PETAR NF soil is less vulnerable to climate changes due to better soil protection by greater vegetation cover, decreasing the exposure to solar radiation and retaining moisture, which favors the stabilization of the microclimate and, consequently, of the ecosystem (Bragagnolo, 1986; Wardle & Parkinson, 1990). A similar finding was obtained for PECJ NF, since no significant differences in MB-N and MB-C were observe in this forest among the sampling periods, although the climate diagram (Figure 2) shows periods of dry weather and sudden temperature drops, reinforcing the important role of the vegetation cover in maintaining biological processes.
Mostrar mais

16 Ler mais

Multi-decadal atmospheric and marine climate variability in southern Iberia during the mid- to late-Holocene

Multi-decadal atmospheric and marine climate variability in southern Iberia during the mid- to late-Holocene

mer rather than a warming of the annual mean SSTs. Such a reaction of the coccolithophores might be also indicated to a lesser extent during Bond event 2 when annual mean SSTs warmed by approximately 1 ◦ C at about 3.2 ka cal BP. Our data does not cover the whole interval though. Also, Bond event 4 is not entirely covered so that this interpreta- tion remains hypothetical. But all in all, the influence of cold water from the North Atlantic during winter along with the influence of warmer subtropical water masses during sum- mer likely resulted in a pronounced seasonality during Bond events 3 and 4 (Fig. 5). Notably, the amplitude of the sea- sonal events and their accordingly high seasonality as well as the overall seasonality in the Gulf of Cádiz were decreas- ing towards the present. It is, moreover, interesting to note that Bond event 2 is not visible in our seasonal SST records at all (Fig. 5). The general decrease in seasonality in the Gulf of Cádiz can be attributed to decreasing summer insolation. We hypothesize that this is also true for the decreasing ampli- tude of the seasonal SST events. During Bond event 4, when summer insolation was high, the more northward position of the ITCZ during summer allowed for a stronger inflow of warmer subtropical water masses into the Gulf of Cádiz. On the other hand, during winter the ITCZ was much further south compared to its present position, allowing enhanced southward flow of the colder water masses from the north. During Bond event 3 the summer and winter positions of the ITCZ were already less extreme, thus weakening the influ- ence of either warm and cold water masses during summer or winter, respectively. Later, during Bond event 2, seasonal movements of the ITCZ were even more limited such that no influence of either cold water masses during winter or warm subtropical water masses during summer is recognizable by a pronounced seasonal temperature difference in the Gulf of Cádiz.
Mostrar mais

18 Ler mais

Toward predicting Dinophysis blooms off NW Iberia: a decade of events

Toward predicting Dinophysis blooms off NW Iberia: a decade of events

high interannual variability of bloom events and summarize the associated meteorological/ oceanographic conditions. D. acuta blooms were observed in 2004–2008 and 2013, and the species highest maxima at AV occurred after the highest maxima of its prey Mesodinium, with a time-lag of 2–3 weeks. D. acuminata blooms were observed every year at both stations. The cell concentration time series shows that the blooms generally present a sequence starting in March with D. acuminata in PO and three weeks later in AV, followed by D. acuta that starts at AV and three months later in PO. Exceptionally, D. acuminata blooms occurred earlier at AV than PO, namely in high spring upwelling (2007) or river runoff (2010) years. A four-year gap (2009–2012) of D. acuta blooms occurred after an anomalous 2008 autumn with intense upwelling which is interpreted as the result of an equatorward displacement of the population core. Numerical model solutions are used to analyze monthly alongshore current anomalies and test transport hypotheses for selected events. The results show a strong interannual variability in the poleward/equatorward currents associated with changes in upwelling forcing winds, the advection of D. acuta blooms from AV to PO and the possibility that D. acuminata blooms at AV might result from inocula advected southward from PO. However, the sensitivity of the results to vertical position of the lagrangian tracers call for more studies on species distribution at the various bloom stages.
Mostrar mais

16 Ler mais

Climate, tectonics and beach erosion : the case of Espinho (nw portuguese coast)

Climate, tectonics and beach erosion : the case of Espinho (nw portuguese coast)

Svensmark and Friis-Christensen (1997) demonstrated a high degree of correlation between total cloud cover and cosmic ray flux between 1984 and 1991. The mechanism is quite complex but can be described in a simple way: when the Sun is more active (more sunspots), the magnetic field that is carried by the solar wind intensifies, creating more auroras (Fig. 2) and providing more shielding from low-energy galactic cosmic rays to the Earth. This effect may lead to a decrease in ion production in the lower atmosphere, resulting in the creation of fewer cloud condensation nuclei and less low-level cloud cover, which will allow more radiation to
Mostrar mais

14 Ler mais

The use of quartz during the Upper Paleolithic and Early Mesolithic in Sabor valley (NW Iberia): The Foz do Medal case

The use of quartz during the Upper Paleolithic and Early Mesolithic in Sabor valley (NW Iberia): The Foz do Medal case

The first major alluvial deposition phase corresponds to channel bottom deposits from the period before the migration of the Sabor course to the opposite margin. The second major deposition phase corresponds to a sequence of massive thick fine-grained deposits. In this phase, some slope contributions are visible, interbedded with the alluvial deposits in the eastern area. The third major sedimentation phase is a thick fine- grained sequence from waning floods. In this phase, the Sabor course was already in its current position which allowed dense and extensive human occupation of the platform. At the base, there is a succession of sand, silt, and mud with horizontal lamination. The first Upper Paleolithic remains (corresponding to Phase II of human occupation) stands on top of this sedimentary unit. A massive silt and sand thick deposit covers this well- preserved occupation. The remains of the Gravettian occupa- tion (Phase III) lay on top of these deposits, and are covered by another massive silt and sand alluvial deposit, on top of which rests the remains of the Magdalenian occupation (Phase IV). Both Gravettian and Magdalenian occupations are not in primary position. The layers with human occupation evidence are separated by alluvial deposits, representative of flood pe- riods, and sometimes indications of slope erosion. The Early Mesolithic occupations are in the upper part of the alluvial sequence. From these phases, we observe different preservation conditions. Several structures and levels were detected. The last prehistoric occupation of the platform was during the Bronze Age ( Gaspar et al., 2014 ) which disturbed some of the previous remains.
Mostrar mais

15 Ler mais

Show all 10000 documents...

temas relacionados