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Potential effects of climate change on the temperate zones of North and South America
LAUENROTH,W.K.; EPSTEIN,H.E.; PARUELO,J.M.; BURKE,I.C.; AGUIAR,M.R.; SALA,O.E.;
Revista chilena de historia natural , 2004, DOI: 10.4067/S0716-078X2004000300004
Abstract: under current conditions, large areas of temperate western north america and temperate southern south america have arid to subhumid climates that make them vulnerable to changes as a result of human-induced climate change. predictions of climate change from global circulation models with a doubling of present atmospheric levels of co2 suggest large changes in mean annual temperature and small to no changes in mean annual precipitation and the proportion of precipitation received during the summer. our objective here was to evaluate how predictions of climate change from global circulation models will influence climatic patterns and by inference the distribution of temperate zone ecosystems in north and south america. calculations of annual water deficits suggest that the area affected by very dry conditions will double as a result of climate change. this expansion will take place in the vicinity of the currently dry areas. monthly water deficit calculations suggest that approximately half of the temperate zone on each continent is affected by at least one month of deficit. under a doubled co2 climate, these areas would expand to cover up to 77 % of the temperate zone of north america and up to 80 % of south america. the resulting changes to the current distribution of ecosystems will likely be an expansion of deserts at the expense of grasslands in north and south america and an expansion of grasslands at the expense of deciduous and boreal forest in north america. our analyses assumed that future climatic changes will be encompassed by the predictions of our three doubled co2 scenarios. the most likely situation is that actual changes, if they occur, will be different from our scenarios. therefore, our analyses should be interpreted as indications of the sensitivity of portions of the north and south american temperate zones to increases in temperature. the key conclusion from our analyses is that any increase in temperature caused by climate change will result in
Potential effects of climate change on the temperate zones of North and South America Potenciales efectos del cambio climático en zonas templadas de América del Norte y del Sur  [cached]
W.K. LAUENROTH,H.E. EPSTEIN,J.M. PARUELO,I.C. BURKE
Revista chilena de historia natural , 2004,
Abstract: Under current conditions, large areas of temperate western North America and temperate southern South America have arid to subhumid climates that make them vulnerable to changes as a result of human-induced climate change. Predictions of climate change from global circulation models with a doubling of present atmospheric levels of CO2 suggest large changes in mean annual temperature and small to no changes in mean annual precipitation and the proportion of precipitation received during the summer. Our objective here was to evaluate how predictions of climate change from global circulation models will influence climatic patterns and by inference the distribution of temperate zone ecosystems in North and South America. Calculations of annual water deficits suggest that the area affected by very dry conditions will double as a result of climate change. This expansion will take place in the vicinity of the currently dry areas. Monthly water deficit calculations suggest that approximately half of the temperate zone on each continent is affected by at least one month of deficit. Under a doubled CO2 climate, these areas would expand to cover up to 77 % of the temperate zone of North America and up to 80 % of South America. The resulting changes to the current distribution of ecosystems will likely be an expansion of deserts at the expense of grasslands in North and South America and an expansion of grasslands at the expense of deciduous and boreal forest in North America. Our analyses assumed that future climatic changes will be encompassed by the predictions of our three doubled CO2 scenarios. The most likely situation is that actual changes, if they occur, will be different from our scenarios. Therefore, our analyses should be interpreted as indications of the sensitivity of portions of the North and South American temperate zones to increases in temperature. The key conclusion from our analyses is that any increase in temperature caused by climate change will result in expansion of the driest portions of both continents Bajo condiciones actuales, extensas áreas de las zonas templadas del oeste de América del Norte y del sur de América del Sur tienen regímenes climáticos áridos a subhúmedos, que son vulnerables a cambios climáticos inducidos por actividades humanas. Predicciones obtenidas a partir de modelos de circulación global bajo una duplicación del CO2 atmosférico sugieren grandes cambios en temperatura media anual, y cambios peque os o nulos en la precipitación media anual y la proporción de precipitación estival. Nuestro objetivo fue evaluar cómo las
Vulnerability of Trees to Climate Events in Temperate Forests of West Germany  [PDF]
Stefanie Fischer,Burkhard Neuwirth
ISRN Forestry , 2013, DOI: 10.1155/2013/201360
Abstract: An improved understanding of the spatiotemporal climate/growth relationship of our forests is of particular importance for assessing the consequences of climate warming. A total of 67 stands of beech (Fagus sylvatica L.), pedunculate oak (Quercus robur L.), sessile oak (Quercus petraea (Matt.) Liebl.), Scots pine (Pinus sylvestris L.), and spruce (Picea abies Karst.) from sites located in the transition zone from the lowlands to the low mountain ranges of West Germany have been analysed. A combination of pointer year and cluster analysis was used to find groups with similar growth anomaly patterns over the 1941–2000 period. Shifted reaction patterns especially characterise differences in the growth behaviour of the clusters. These are controlled by different reactions to the climate conditions in winter and spring and are determined by a complex system of forcing factors. Results of this study reflect the enormous importance of the length of the growing season. Increasing the duration of the vegetation period climate warming can change the climate/growth relationship of trees, thereby confounding climate reconstructions which use tree rings. Since forcing factors have been detected that are more important than the tree species, we recommend the application of growth-specific approaches for the analysis of tree species’ vulnerability to climate. 1. Introduction Whereas tree growth at the timberline is mostly limited by only one specific dominant factor [1], growth of temperate forest regions is influenced by a multitude of biotic and abiotic factors [2–4]. This is caused by predominant temperate climate conditions and the fact that mostly native tree species are growing in the range of their natural distribution areas [5]. Nevertheless, climate control is still a crucial forcing factor for annual tree-ring growth in lower altitudes [3]. The 20th century warming trends are extraordinary [6] and steady since the late 1970s [7] and have lengthened the duration of the growing season [8]. An increase of severe climate extremes such as heat waves is inherent with these [9], whereas changes in precipitation and dryness extremes are less clearly linked [10]. However, a better understanding of the spatiotemporal climate/growth relationships, including the identification of the environmental drivers, is of particular importance [11–13] to understand climate-induced changes in forest productivity with regard to different tree species and site characteristics. Previous studies have shown that analyses of tree-ring width at lower elevation sites are suitable for
Climate-Induced Changes in Grapevine Yield and Must Sugar Content in Franconia (Germany) between 1805 and 2010  [PDF]
Anna Bock, Tim H. Sparks, Nicole Estrella, Annette Menzel
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0069015
Abstract: When attempting to estimate the impacts of future climate change it is important to reflect on information gathered during the past. Understanding historical trends may also aid in the assessment of likely future agricultural and horticultural changes. The timing of agricultural activities, such as grape harvest dates, is known to be influenced by climate and weather. However, fewer studies have been carried out on grapevine yield and quality. In this paper an analysis is undertaken of long-term data from the period 1805–2010 on grapevine yield (hl/ha) and must sugar content (°Oe) and their relation to temperature. Monthly mean temperatures were obtained for the same time period. Multiple regression was used to relate the viticulture variables to temperature, and long-term trends were calculated. Overall, the observed trends over time are compatible with results from other long term studies. The findings confirm a relationship between yield, must sugar content and temperature data; increased temperatures were associated with higher yields and higher must sugar content. However, the potential increase in yield is currently limited by legislation, while must sugar content is likely to further increase with rising temperatures.
Classifying Urban Climate Field Sites by “Thermal Climate Zones” the Case of Onitsha Metropolis  [cached]
I.C. Nduka,A.I. Abdulhamed
Research Journal of Environmental and Earth Sciences , 2011,
Abstract: The study is about testing the first phase of the new urban climate zoning scheme. The idea behind this work is to test this scheme in a city that is in the developing world with all its antecedent environmental and planning problems. This research tried to demonstrate a possible new approach to site classification using a system of “Thermal Climate Zones”, and these zones were tested using the “urban” and “mixed” field sites in Onitsha metropolis. The results show that Onitsha sites correspond well with Thermal Climate zones; the zones observed include TCZ2 (old core), TCZ 3 (compact housing), TCZ 5 (Blocks), TCZ 6 (extensive lowrise), TCZ 7 (Regular housing), TCZ 8 (shanty town), TCZ 9 (open grounds) and TCZ 20 (dispersed settlements). Moreso, the major difference observed by the researcher is the difference in surface cover in some categories or zones. The new system provides a more useful interpretation of the landscape for urban climatologists. With further refinement, Thermal Climate Zones can improve consistency and accuracy in urban climate reporting.
Annual and Daily Changes of Thunderstorms in Temperate Climate in London, Warsaw and Moscow
Katarzyna Grabowska
Miscellanea Geographica - Regional Studies on Development , 2011, DOI: 10.2478/v10288-012-0007-4
Abstract: The aim of the study is to show and compare variation of the annual and daily course of thunderstorms in selected European cities in 2005-2009. Data on thunderstorms originate from dispatches METAR for three airport stations: London Gatwick, Warsaw Ok cie and Moscow Sheremetyevo. These cities represent the various types of climate: warm temperate marine, transitional and continental. Thunderstorms mostly occurred in Warsaw - 207 (Moscow - 174, London - 71). The maximum of thunderstorms frequency, in the yearly course, in all towns occurred in July (Warsaw - 11,8; Moscow - 13,4; London - 5,0). Thunderstorms predominantly started at 13:30 in London, 17:00 in Warsaw, 18:00 in Moscow (13:30 means period 13:01-13:30, 17:00 means period 16:31-17:00 etc.). Thunderstorms most often ended at 13:30 in London, 17:00 in Warsaw, 20:30 in Moscow. There were dominated, at all stations, brief thunderstorms, which lasted for 30 minutes. The longest thunderstorm remained 9 hours (Warsaw), 5,5 (Moscow), 4,5 (London).
Ecophysiological and anatomical characteristics of the subtropical shrub Zanthoxylum acanthopodium (Rutaceae) in conditions of a temperate continental climate (Serbia)  [PDF]
Raki? Tamara,?in?ar-Sekuli? Jasmina,Filipovi? Biljana,Tadi? Vanja
Archives of Biological Sciences , 2009, DOI: 10.2298/abs0902249r
Abstract: The evergreen shrub Zanthoxylum acanthopodium DC. (Rutaceae), originating from warm temperate and subtropical Asia, has existed successfully in the Jevremovac Botanical Garden in Belgrade for more than 80 years. The seasonal pattern of water management in leaves, electrolyte leakage, essential oil composition, and leaf anatomy were examined in order to understand the resistance and viability of this subtropical shrub in the temperate continental climate of Belgrade, Serbia.
Defining climate zones in México City using multivariate analysis
ESTRADA, F.;MARTíNEZ-ARROYO, A.;FERNáNDEZ-EGUIARTE, A.;LUYANDO, E.;GAY, C.;
Atmósfera , 2009,
Abstract: spatial variability in the climate of méxico city was studied using multivariate methods to analyze 30 years of meteorological data from 37 stations (from the servicio meteorológico nacional) located within the city. although it covers relatively small area, méxico city encompasses considerable climatic heterogeneity, due mainly to the contrasts in elevation and land use within its territory. multivariate methods were used in this study to reduce the dimensionality of the variables reported by the weather stations, to define climate indexes for representing the main features of méxico city's climate more compactly, as well as to identify geographic zones with similar climatic characteristics. the results of the study contribute additional evidence of the important influence of orography and urbanization on climates in cities. two large regions and four subregions with similar climatic characteristics were identified in this study: low altitude suburban, low altitude highly urbanized, urbanized mountain base, and higher elevation with forests. three climate indices were also defined. the three indexes are related to temperature and precipitation, to days with fog and with electrical storms, and to days with hail and low temperatures. the results of this study suggest that multivariate analysis can be a useful tool for urban planning and for tracking the impact of anthropogenic factors on microclimate.
Estimating Climate Trends: Application to United States Plant Hardiness Zones  [PDF]
Nir Y. Krakauer
Advances in Meteorology , 2012, DOI: 10.1155/2012/404876
Abstract: The United States Department of Agriculture classifies plant hardiness zones based on mean annual minimum temperatures over some past period (currently 1976–2005). Since temperatures are changing, these values may benefit from updating. I outline a multistep methodology involving imputation of missing station values, geostatistical interpolation, and time series smoothing to update a climate variable’s expected value compared to a climatology period and apply it to estimating annual minimum temperature change over the coterminous United States. I show using hindcast experiments that trend estimation gives more accurate predictions of minimum temperatures 1-2 years in advance compared to the previous 30 years’ mean alone. I find that annual minimum temperature increased roughly 2.5 times faster than mean temperature (~2.0?K?versus?~0.8?K since 1970), and is already an average of 1.2? ?0.5?K (regionally up to ~2?K) above the 1976–2005 mean, so that much of the country belongs to warmer hardiness zones compared to the current map. The methods developed may also be applied to estimate changes in other climate variables and geographic regions. 1. Introduction Expected values of various climate variables at particular locations are used for decision making in many sectors. Traditionally, these have been estimated based on the average over some past period. If the variable is statistically stationary, averaging over a long period should result in an accurate estimate of its expected value; however, in the presence of trends, such as those associated with global warming, such averages will not be optimal estimates for the expected value going forward [1, 2]. In this paper, the climate variable considered is the annual minimum temperature, an important determinant of the range over which particular varieties of perennial plants and overwintering insects may thrive. The United States Department of Agriculture (USDA) first released maps of plant hardiness zones for the coterminous United States (USA) and southern Canada in 1960, where each zone corresponded to a particular range of mean annual minimum temperature; similar maps, with different numbering of hardiness zones, were published as early as 1938 by Harvard University's Arnold Arboretum [3]. The most recent USDA hardiness zone map revision for the United States and Puerto Rico, published in January 2012, is based on mean annual minimum temperatures over 1976–2005 at some 8,000 available weather stations, interpolated to a resolution finer than 1?km taking into account factors such as elevation and proximity
Assessment of Patterns of Climate Variables and Malaria Cases in Two Ecological Zones of Ghana  [PDF]
Nana Ama Browne Klutse, Fred Aboagye-Antwi, Kwadwo Owusu, Yaa Ntiamoa-Baidu
Open Journal of Ecology (OJE) , 2014, DOI: 10.4236/oje.2014.412065
Abstract: Climate change is projected to impact human health, particularly incidence of water related and vector borne diseases, such as malaria. A better understanding of the relationship between rainfall patterns and malaria cases is thus required for effective climate change adaptation strategies involving planning and implementation of appropriate disease control interventions. We analyzed climatic data and reported cases of malaria spanning a period of eight years (2001 to 2008) from two ecological zones in Ghana (Ejura and Winneba in the transition and coastal savannah zones respectively) to determine the association between malaria cases, and temperature and rainfall patterns and the potential effects of climate change on malaria epidemiological trends. Monthly peaks of malaria caseloads lagged behind monthly rainfall peaks. Correlation between malaria caseloads and rainfall intensity, and minimum temperature were generally weak at both sites. Lag correlations of up to four months yielded better agreement between the variables, especially at Ejura where a two-month lag between malaria caseloads and rainfall was significantly high but negatively correlated (r = -0.72; p value < 0.05). Mean monthly maximum temperature and monthly malaria caseloads at Ejura showed a strong negative correlation at zero month lag (r = -0.70, p value < 0.05), with a similar, but weaker relationship at Winneba, (r = -0.51). On the other hand, a positive significant correlation (r = 0.68, p value < 0.05) between malaria caseloads and maximum temperature was observed for Ejura at a four-month lag, while Winneba showed a strong correlation (r = 0.70; p value < 0.05) between the parameters at a two-month lag. The results suggest maximum temperature as a better predictor of malaria trends than minimum temperature or precipitation, particularly in the transition zone. Climate change effects on malaria caseloads seem multi-factorial. For effective malaria control, interventions could be synchronized with the most important climatic predictors of the disease for greater impact.
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