|Abstracts on Global Climate Change|
The human role in changing river channels
GEOMORPHOLOGY 79:3-4 172-191
Direct consequences of the human role, where human activity affects river channels through engineering works including channelization, dam construction, diversion and culverting, have been long recognised [Marsh, G.P., 1864. Man and Nature or Physical Geography as Modified by Human Action. Charles Scribner, New York; Thomas Jr., W.L., (ed.) 1956. Man’s Role in Changing the Face of the Earth. Chicago, University of Chicago Press, Chicago.]. The less obvious indirect effects of point and reach changes occurring downstream and throughout the basin, however, are much more recently appreciated, dating from key contributions by Strahler [Strahler, A.N., 1956. The nature of induced erosion and aggradation. In W. L. Thomas (Ed.), Man’s Role in Changing the Face of the Earth. University of Chicago Press, Chicago, 621-638.], Wohnan [Wolman, M.G., 1967. A cycle of sedimentation and erosion in urban river channels. Geografiska Annaler 49A, 385-95.], Schumm [Schumm, S.A., 1969. River metamorphosis. Proceedings American Society of Civil Engineers, Journal Hydraulics Division 95, 255-73.], and Graf [Graf, W.L., 1977. The rate law in fluvial geomorphology. American Journal of Science, 277, 178-191.]. These are complemented by effects of alterations of land use, such as deforestation, intensive agriculture and incidence of fire, with the most extreme effects produced by building activity and urbanisation. Changing river channels are most evident in the channel cross-section where changes of size, shape and composition are now well-established, with up to tenfold increases or decreases illustrated by results from more than 200 world studies. In addition the overall channel planform, the network and the ecology have changed. Specific terns have become associated with changing river channels including enlargement, shrinkage and metamorphosis. Although the scope of adjustment has been established, it has not always been possible to predict what will happen in a particular location, because of complex response and contingency. The ways in which changes in cross-section relate to reach and network changes are less clear, despite investigations showing the distribution of changes along segmented channels. When considering the human role in relation to changing river channels, at least five challenges persist. First, because prediction of the nature and amount of likely change at a particular location is not certain, and because the contrasting responses of humid and arid systems needs to be considered, modelling is required to reduce uncertainty, as was first emphasised by Burkham [Burkham, D.E., 1981. Uncertainties resulting from changes in river form. American Society Civil Engineers Proceedings, Journal Hydraulics Division 107, 593-610.]. Second, feedback effects incorporated within the relationship between changes at channel, reach and network scales can have considerable implications, especially because changes now evident may have occurred, or have been initiated, under different environmental conditions. Third, consideration of global climate change is imperative when considering channel sensitivity and responses to threshold conditions. Fourth, channel design involving geomorphology should now be an integral part of restoration procedures. This requires, fifthly, greater awareness of different cultures as a basis for understanding constraints imposed by legislative frameworks. Better understanding of the ways in which the perception of the human role in changing river channels varies with culture as well as varying over time should enhance application of design for river channel landscapes. (c) 2006 Elsevier B.V. All rights reserved.
The economic impact of global climate change on Mediterranean rangeland ecosystems: A Space-for-Time approach
Fleischer, A Sternberg, M
ECOLOGICAL ECONOMICS 59:3 287-295
Global Climate Change (GCC) can bring about changes in ecosystems and consequently in their services value. Here we show that the urban population in Israel values the green landscape of rangelands in the mesic Mediterranean climate region and is willing to pay for preserving it in light of the expected increasing aridity conditions in this region. Their valuation of the landscape is higher than that of the grazing services these rangelands provide for livestock growers. These results stem from a Time-for-Space approach with which we were able to measure changes in biomass production and rainfall at four experimental sites along an aridity gradient. (c) 2005 Elsevier B.V. All rights reserved.
A pilot test of a new stated preference valuation method: Continuous attribute-based stated choice
Ready, R Fisher, A Guignet, D Stedman, R Wang, JC
ECOLOGICAL ECONOMICS 59:3 247-255
A new stated preference nonmarket valuation technique is developed. In an interactive computerized survey, respondents move continuous sliders to vary levels of environmental attributes. The total cost of the combination of attributes is calculated according to a preprogrammed cost function, continuously updated and displayed as respondents move the sliders. Each registered choice reveals the respondent’s marginal willingness to pay for each of the attributes. The method is tested in a museum exhibit on global climate change. Two construct validity tests were conducted. Responses are sensitive to the shape of the cost function in ways that are consistent with expectations based on economic theory. implied marginal willingness to pay values were similar to those estimated using a more traditional paired comparisons stated choice format. However, responses showed range effects that indicate potential cognitive biases. (c) 2005 Elsevier B.V. All rights reserved
A phyloclimatic study of Cyclamen
Yesson, C Culham, A
BMC EVOLUTIONARY BIOLOGY 6: -
Background: The impact of global climate change on plant distribution, speciation and extinction is of current concern. Examining species climatic preferences via bioclimatic niche modelling is a key tool to study this impact. There is an established link between bioclimatic niche models and phylogenetic diversification. A next step is to examine future distribution predictions from a phylogenetic perspective. We present such a study using Cyclamen (Myrsinaceae), a group which demonstrates morphological and phenological adaptations to its seasonal Mediterranean-type climate. How will the predicted climate change affect future distribution of this popular genus of garden plants? Results: We demonstrate phylogenetic structure for some climatic characteristics, and show that most Cyclamen have distinct climatic niches, with the exception of several wide-ranging, geographically expansive, species. We reconstruct climate preferences for hypothetical ancestral Cyclamen. The ancestral Cyclamen lineage has a preference for the seasonal Mediterranean climate characteristic of dry summers and wet winters. Future bioclimatic niches, based on BIOCLIM and Maxent models, are examined with reference to a future climate scenario for the 2050s. Over the next 50 years we predict a northward shift in the area of climatic suitability, with many areas of current distribution becoming climatically unsuitable. The area of climatic suitability for every Cyclamen species is predicted to decrease. For many species, there may be no areas with a suitable climate regardless of dispersal ability, these species are considered to be at high risk of extinction. This risk is examined from a phylogenetic perspective. Conclusion: Examining bioclimatic niches from a phylogenetic perspective permits novel interpretations of these models. In particular, reconstruction of ancestral niches can provide testable hypothesis about the historical development of lineages. In the future we can expect a northwards shift in climatic suitability for the genus Cyclamen. If this proves to be the case then dispersal is the best chance of survival, which seems highly unlikely for ant-dispersed Cyclamen. Human-assisted establishment of Cyclamen species well outside their native ranges offers hope and could provide the only means of dispersal to potentially suitable future environments. Even without human intervention the phylogenetic perspective demonstrates that major lineages could survive climate change even if many species are lost.
Increase of alien and C-4 plant species in annual river bank vegetation of the River Rhine
PHYTOCOENOLOGIA 36:3 393-402
Recent and historic releves of the annual river bank vegetation (Polygono brittingeri-Chenopodictum rubri, Chenopodium rubrum subassociation) of the middle and lower River Rhine (Germany) were evaluated with regard to their representation of alien and C, plant species. The releves evaluated covered a period of more than 50 years from the second half of the 20,h to the beginning of the 21(st) century. There was a distinct increase in the proportion of alien and C, plant species: The mean percentage of post-1492 aliens (neophytes) increased from 9.9% in 1964 to 27.5% in 2002. In the same period, the mean percentage of C-4 plants increased from 4.4% to 11.5%. In 1998 - 2002 99 alien plant species were recorded in the annual sand and gravel bank vegetation of the study area. Possible reasons for the increase of alien and C, plants may include increased trade activities and increased temperatures due to global climate change.
Conserving and increasing biodiversity in the large-scale, intensive farming systems of the Western Cape, South Africa
SOUTH AFRICAN JOURNAL OF SCIENCE 102:9-10 375-378
The Convention on Biological Diversity, adopted in 1992 in Nairobi and signed by many states, including South Africa, at the United Nations Conference on Environment and Development in Rio de Janeiro later that year, urges nations to conserve biological diversity. This places a special responsibility on farmers, who own most of the land. Yet agricultural practices usually aim at simplifying ecosystems in favour of the crops (and animals) that are produced. In the Western Cape province of South Africa, this process has resulted in extensive monocultures of wheat, grapevines and fruit trees. The questions arise: should farmers bring more biodiversity back into these systems and, if so, how can they do it? Apart from the moral obligation to do so, perceived benefits include the possibility of greater economic and ecological stability, especially under conditions of global climate change; enhanced aesthetic appeal and greater acceptance of farming practices by the public in general and purchasers of farm produce in particular. Possible disadvantages are short-term losses in productivity and profitability. Measures that will contribute towards increasing biodiversity include: intercropping; the planting and maintenance of shelter belts, buffer strips and natural corridors; retaining riparian and other areas of high value natural vegetation; making dams attractive to wildlife; reducing the impact of pesticides; educating farmers and farm workers about the values of biodiversity conservation; and providing financial incentives to landowners for biodiversity conservation. An overview is provided in this paper of current international and national biodiversity conservation policies and programmes and some of the local initiatives that are active in the Western Cape to protect and re-establish biodiversity.
Extreme precipitation over the Maritime Alps and associated weather regimes simulated by a regional climate model: Present-day and future climate scenarios
Boroneant, C Plaut, G Giorgi, F Bi, X
THEORETICAL AND APPLIED CLIMATOLOGY 86:1-4 81-99
We use the regional climate model RegCM nested within time-slice atmospheric general circulation model experiments to investigate the possible changes of intense and extreme precipitation over the French Maritime Alps in response to global climate change. This is a region with complex orography where heavy and/or extended precipitation episodes induced catastrophic floods during the last decades. Output from a 30-year simulation of present-day climate (1961-1990) is first analysed and compared with NCEP reanalysed 700 CehPa geopotential heights (Z700) and daily precipitation observations from the Alpine Precipitation Climatology (1966-1999). Two simulations under forcing from the A2 and B2 IPCC emission scenarios for the period 2071-2100 are used to investigate projected changes in extreme precipitation for our region of interest. In general, the model overestimates the annual cycle of precipitation. The climate change projections show some increase of precipitation, mostly outside the warm period for the B2 scenario, and some increase in the variability of the annual precipitation totals for the A2 scenario. The model reproduces the main observed patterns of the spatial leading EOFs in the Z700 field over the Atlantic-European domain. The simulated large scale circulation (LSC) variability does not differ significantly from that of the reanalysis data provided the EOFs are computed on the same domain. Two similar clusters of LSC corresponding to heavy precipitation days were identified for both simulated and observed data and their patterns do not change significantly in the climate change scenarios. The analysis of frequency histograms of extreme indices shows that the control simulation systematically underestimates the observed heavy precipitation expressed as the 90(th) percentile of rainday amounts in all seasons except summer and better reproduces the greatest 5-day precipitation accumulation. The main hydrological changes projected for the Maritime Alps consist of an increase of most intense wet spell precipitation during winters for both scenarios and during autumn for the B2 scenario. Case studies of heavy precipitation events show that the RegCM is capable to reproduce the physical mechanisms responsible for heavy precipitation over our region of interest.
A synthesis of bentho-pelagic coupling on the Antarctic shelf: Food banks, ecosystem inertia and global climate change
Smith, CR Mincks, S DeMaster, DJ
DEEP-SEA RESEARCH PART II-TOPICAL STUDIES IN OCEANOGRAPHY 53:8-10 875-894
The Antarctic continental shelf is large, deep (500-1000 m), and characterized by extreme seasonality in sea-ice cover and primary production. Intense seasonality and short pelagic foodwebs on the Antarctic shelf may favor strong benthopelagic coupling, whereas unusual water depth combined with complex topography and circulation could cause such coupling to be weak. Here, we address six questions regarding the nature and strength of coupling between benthic and water-column processes on the continental shelf surrounding Antarctica. We find that water-column production is transmitted to the shelf floor in intense pulses of particulate organic matter, although these pulses are often difficult to correlate with local phytoplankton blooms or sea-ice conditions. On regional scales, benthic habitat variability resulting from substrate type, current regime, and iceberg scour often may obscure the imprint of water-column productivity on the seafloor. However, within a single habitat type, i.e. the muddy sediments that characterize much of the deep Antarctic shelf, macrobenthic biomass appears to be correlated with regional primary production and sea-ice duration. Over annual timescales, many benthic ecological processes were initially expected to vary in phase with the extraordinary boom/bust cycle of production in the water column. However, numerous processes, including sediment respiration, deposit feeding, larval development, and recruitment, often are poorly coupled to the summer bloom season. Several integrative, time-series studies on the Antarctic shelf suggest that this lack of phasing may result in part from the accumulation of a persistent sediment food bank that buffers the benthic ecosystem from the seasonal variability of the water column. As a consequence, a variety of benthic parameters (e.g., sediment respiration, inventories of labile organic matter, macrobenthic biomass) may act as “low-pass” filters, responding to longer-term (e.g., inter-annual) trends in water-column production. Bentho-pelagic coupling clearly will be altered by Antarctic climate change as patterns of sea-ice cover and water-column recycling vary. However, the nature of such climate-driven changes will be very difficult to predict without further studies of Antarctic benthic ecosystem response to (1) inter-annual variability in export flux, and (2) latitudinal gradients in duration of sea-ice cover and benthic ecosystem function. (c) 2006 Elsevier Ltd. All rights reserved.
Catastrophe, recovery and range limitation in NE Pacific kelp forests: a large-scale perspective
Edwards, MS Estes, JA
MARINE ECOLOGY-PROGRESS SERIES 320: 79-87
The 1997-98 El Nino was one of the strongest on record and resulted in widespread losses of the giant kelp Macrocystis pyrifera (Agardh) along the west coast of North America. Drawing on a rich history of studies that have shown abnormally large waves and warm nutrient-poor water associated with El Ninos to negatively impact giant kelp populations at some locations in southern and Baja California, we examined (1) how these impacts scale up when considered across the species’ geographic range in the NE Pacific Ocean and (2) if these impacts are generalizable over broad spatial scales. Working at 56 sites in 14 study locations over a 3 yr period (1997 to 2000), we examined how giant kelp populations were impacted by and recovered following the 1997-98 El Niho over a similar to 1500 km span along the west coast of North America. Our results indicate that while nearly all giant kelp disappeared from the southern one-third of the species’ range along the coast of Baja California, Mexico, and heavy losses occurred throughout the central one-third of the species’ range in southern California, USA, only minor impacts were observed throughout the northern one-third of the species’ range in central California. Further, although highly variable among regions, these impacts were similar and generalizable among locations within each region. Our results also suggest that, as has been observed in local-scale studies, this large-scale variability in giant kelp mortality was driven by large-scale patterns in ocean temperature (nutrient concentration) and wave intensity. Recovery following El Niho, in contrast, was variable at multiple spatial scales and although not directly tested here, presumably influenced by numerous factors such as proximity to upwelling areas, competition with other algae, grazing, and propagule availability. Further, variability in the rates of recovery among locations resulted in a generally slow recovery of giant kelp throughout most of Baja California, and residual large-scale impacts of the El Niho were still evident 2 yr after the El Niho ended. As global climate change may lead to increases in the frequency and intensity of El Ninos, our findings have broad implications for the ways in which ecosystems might be expected to respond to them and provide a measure by which their impacts to giant kelp ecosystems may be compared among events.
Climate change manipulations show Antarctic flora is more strongly affected by elevated nutrients than water
Wasley, J Robinson, SA Lovelock, CE Popp, M
GLOBAL CHANGE BIOLOGY 12:9 1800-1812
Climate change is expected to affect the high latitudes first and most severely, rendering Antarctica one of the most significant baseline environments for the study of global climate change. The indirect effects of climate warming, including changes to the availability of key environmental resources, such as water and nutrients, are likely to have a greater impact upon continental Antarctic terrestrial ecosystems than the effects of fluctuations in temperature alone. To investigate the likely impacts of a wetter climate on Antarctic terrestrial communities a multiseason, manipulative field experiment was conducted in the floristically important Windmill Islands region of East Antarctica. Four cryptogamic communities (pure bryophyte, moribund bryophyte, crustose and fructicose lichen-dominated) received increased water and/or nutrient additions over two consecutive summer seasons. The increased water approximated an 18% increase in snow melt days (0.2 degrees C increase in temperature), while the nutrient addition of 3.5g Nm(-2) yr(-1) was within the range of soil N in the vicinity. A range of physiological and biochemical measurements were conducted in order to quantify the community response. While an overall increase in productivity in response to water and nutrient additions was observed, productivity appeared to respond more strongly to nutrient additions than to water additions. Pure bryophyte communities, and lichen communities dominated by the genus Usnea, showed stronger positive responses to nutrient additions, identifying some communities that may be better able to adapt and prosper under the ameliorating conditions associated with a warmer, wetter future climate. Under such a climate, productivity is overall likely to increase but some cryptogamic communities are likely to thrive more than others. Regeneration of moribund bryophytes appears likely only if a future moisture regime creates consistently moist conditions.
Growth responses of two dominant C4 grass species to altered water availability
Swemmer, AM Knapp, AK Smith, MD
INTERNATIONAL JOURNAL OF PLANT SCIENCES 167:5 1001-1010
Identifying key ecophysiological traits that differ among dominant plant species and can be linked to species-specific responses to drought would improve our ability to forecast community and ecosystem responses to global climate change. The mesic grasslands of the central plains of North America are dominated by two C-4 grass species, Andropogon gerardii and Sorghastrum nutans, which purportedly differ in their tolerance of water stress. Individuals of these two species were grown in the field under rain-out shelters and subjected to wet (watered every 2-3 d) or dry (repeatedly subjected to wilting before watering) soil moisture regimes. A range of ecophysiological traits potentially important for tolerating water stress were concurrently measured. Although few traits differed between the species in the wet treatment, several traits were identified in the dry treatment that may enable A. gerardii to better tolerate drought. These were greater allocation to roots, reduced allocation to flowering, more rapid leaf turnover, and more rapid recovery of photosynthesis after wilting. The latter two traits may be particularly important for coping with increased variability in rainfall regimes in the future and are consistent with recently documented responses of A. gerardii to experimental increases in soil moisture variability.
Middle Pleistocene glacier behaviour in the Mediterranean: sedimentological evidence from the Pindus Mountains, Greece
Hughes, PD Gibbard, PL Woodward, JC
JOURNAL OF THE GEOLOGICAL SOCIETY 163: 857-867
Detailed sedimentological analyses of diamicton sequences in two areas of the Pindus Mountains, Greece, indicate multiple episodes of glacier advance and retreat during cold stages of the Middle-Pleistocene. These glacial sequences represent some of the most southerly in Europe and are important archives of regional and global climate change. The Pindus glaciers were relatively small by world standards and would have been highly responsive to changes in air temperature and precipitation. On Mount Tymphi, at least three phases of glacier advance are recorded within deposits assigned to the Skamnellian Stage (MIS 12). Further north on Mount Smolikas, a thick multiple diamicton sequence records evidence for multiple glacier advances during both the Skamnellian Stage and the Vlasian Stage (MIS 6). These records highlight the dynamic nature of glacier behaviour in the Mediterranean mountains during the Middle Pleistocene and provide new evidence for unstable cold stage climates.
Accumulation and release of methane from clathrates below the Laurentide and Cordilleran ice sheets
Weitemeyer, KA Buffett, BA
GLOBAL AND PLANETARY CHANGE 53:3 176-187
Ice-age cycles are associated with large fluctuations in the concentration of atmospheric methane. These fluctuations are commonly attributed to changes in wetlands, although clathrates have also been proposed as a potential source. We examine the possibility that methane clathrates accumulate below continental ice sheets during an ice age. The source of methane is due to microbial decomposition of organic material below the ice sheet. Methane is stored in clathrate when the pressure and temperature conditions permit thermodynamic stability. Deglaciation releases methane from clathrate into the atmosphere. We use a numerical model for the Laurentide-Cordilleran ice sheet [Marshall, S.J., Tarasov, L., Clarke, G.K.C., Peltier, W.R., 2000. Glaciological reconstruction of the Laurentide ice sheet: physical processes and modeling challenges, Can. J. Earth Sci. 37, 769-793.] to assess the aerial extent, thickness, and the thermal conditions at the base of the ice sheet as a function of time. Both low and high inventories of the organic carbon below the ice sheet are considered, based on soil carbon estimates for tundra and for the present potential vegetation. We model the spatial distribution of clathrate as the ice sheet grows and quantify the amplitude and timing of methane releases as the ice sheet retreats. The predicted fluctuations in atmospheric methane are 80-200 ppbv, which are comparable to fluctuations recorded in ice cores from Greenland and Antarctica. However, clathrates cannot explain the entire atmospheric methane record because there is insufficient methane in clathrate to sustain the elevated atmospheric concentration for more than 1 kyr. (C) 2006 Elsevier B.V. All rights reserved.
Toward synthesis of relationships among leaf longevity, instantaneous photosynthetic rate, lifetime leaf carbon gain, and the gross primary production of forests
Kikuzawa, K Lechowicz, MJ
AMERICAN NATURALIST 168:3 373-383
The assimilation of carbon by plant communities (gross primary production [GPP]) is a central concern in plant ecology as well as for our understanding of global climate change. As an alternative to traditional methods involving destructive harvests or time-consuming measurements, we present a simple, general model for GPP as the product of the lifetime carbon gain by a single leaf, the daily leaf production rate, and the length of the favorable period for photosynthesis. To test the model, we estimated leaf lifetime carbon gain for 26 species using the concept of mean labor time for leaves (the part of each day the leaf functions to full capacity), average potential photosynthetic capacity over the leaf lifetime, and functional leaf longevity (leaf longevity discounted for periods within a year wholly unfavorable for photosynthesis). We found that the lifetime carbon gain of leaves was rather constant across species. Moreover, when foliar biomass was regressed against functional leaf longevity, aseasonal and seasonal forests fell on a single line, suggesting that the leaf production rate during favorable periods is not substantially different among forests in the world. The gross production of forest ecosystems then can be predicted to a first approximation simply by the annual duration of the period favorable for photosynthetic activity in any given region.
An Arctic-breeding bird survey on the northwestern Ungava Peninsula, Quebec, Canada
ARCTIC 59:3 311-318
Knowledge of breeding bird distribution and abundance in the Canadian Arctic remains rudimentary for many species, particularly for shorebirds and songbirds. To help fill this gap, randomly selected plots were surveyed on the northwestern coast of the Ungava Peninsula, Quebec, Canada, during 2002. Thirty-eight species were recorded at 34 sites, where small songbirds were much more frequent than shorebirds. Breeding waterbirds were more abundant at low elevations near the coast, and songbirds tended to be more abundant at higher elevations. A high occurrence of nesting hawks and owls was probably the result of a high lemming population. Information from the survey extended the known breeding ranges of green-winged teal, spotted sandpiper, pectoral sandpiper, dunlin, American golden-plover, Wilson’s snipe, and short-eared owl. Further work on the Ungava Peninsula would likely document additional Arctic-breeding bird species. A more thorough knowledge of Arctic-breeding bird distribution will be needed to determine how species might be affected by global climate change.
The global-scale temperature and moisture dependencies of soil organic carbon decomposition: an analysis using a mechanistic decomposition model
Ise, T Moorcroft, PR
BIOGEOCHEMISTRY 80:3 217-231
Since the decomposition rate of soil organic carbon (SOC) varies as a function of environmental conditions, global climate change is expected to alter SOC decomposition dynamics, and the resulting changes in the amount of CO2 emitted from soils will feedback onto the rate at which climate change occurs. While this soil feedback is expected to be significant because the amount of SOC is substantially more than the amount of carbon in the atmosphere, the environmental dependencies of decomposition at global scales that determine the magnitude of the soil feedback have remained poorly characterized. In this study, we address this issue by fitting a mechanistic decomposition model to a global dataset of SOC, optimizing the model’s temperature and moisture dependencies to best match the observed global distribution of SOC. The results of the analysis indicate that the temperature sensitivity of decomposition at global scales (Q(10)=1.37) is significantly less than is assumed by many terrestrial ecosystem models that directly apply temperature sensitivity from small-scale studies, and that the maximal rate of decomposition occurs at higher moisture values than is assumed by many models. These findings imply that the magnitude of the soil decomposition feedback onto rate of global climate change will be less sensitive to increases in temperature, and modeling of temperature and moisture dependencies of SOC decomposition in global-scale models should consider effects of scale.
General equilibrium effects of a supply side GHG mitigation option under the Clean Development Mechanism
Timilsina, GR Shrestha, RM
JOURNAL OF ENVIRONMENTAL MANAGEMENT 80:4 327-341
The Clean Development Mechanism (CDM) under the Kyoto Protocol to the United Nations Framework Convention on Climate Change is considered a key instrument to encourage developing countries’ participation in the mitigation of global climate change. Reduction of greenhouse gas (GHG) emissions through the energy supply and demand side activities are the main options to be implemented under the CDM. This paper analyses the general equilibrium effects of a supply side GHG mitigation option-the substitution of thermal power with hydropower-in Thailand under the CDM. A static multi-sector general equilibrium model has been developed for the purpose of this study. The key finding of the study is that the substitution of electricity generation from thermal power plants with that from hydropower plants would increase economic welfare in Thailand. The supply side option would, however, adversely affect the gross domestic product (GDP) and the trade balance. The percentage changes in economic welfare, GDP and trade balance increase with the level of substitution and the price of certified emission reduction (CER) units. (c) 2006 Elsevier Ltd. All rights reserved.
Energy prices and turning points: The relationship between income and energy use/carbon emissions
Richmond, AK Kaufmann, RK
ENERGY JOURNAL 27:4 157-180
Models used to test whether an environmental Kuznets curve (EKC) can be used to describe the relationship between GDP and energy use and/or carbon emissions may be biased by the omission of energy prices. Here we include real energy prices and fuel shares in models that describe energy use and carbon emissions. We test if these models show a turning point in OECD countries. Results indicate that including energy prices eliminates statistical support for a turning point and suggest that the relationship between income and both energy use and carbon emissions is represented most accurately by diminishing returns. These results imply that economic growth per se will not reduce energy use or emissions that cause global climate change.
Level physiology, biomass, and reproduction of Phytolacca americana under conditions of elevated carbon dioxide and increased nocturnal temperature
Wolfe-Bellin, KS He, JS Bazzaz, FA
INTERNATIONAL JOURNAL OF PLANT SCIENCES 167:5 1011-1020
Rising atmospheric CO2 and increasing air temperatures are predicted to increase future plant growth, but plant responses to increasing temperatures could be complicated by the fact that nocturnal temperatures may increase more than diurnal temperatures. The C-3 forb Phytolacca americana L. (Phytolaccacea) was grown under either ambient (370 mu mol mol(-1)) or elevated (740 mmol mol(-1)) CO2 in either of two nocturnal temperature treatments (26 degrees/20 degrees C or 26 degrees/24 degrees C day/night). We predicted that elevated CO2 would increase photosynthetic rate and enhance plant biomass, while elevated nocturnal temperature would increase dark respiration rate and decrease biomass. Thus, increased nocturnal temperature was predicted to diminish the generally positive effects of elevated CO2 on plant growth. Plants grown under elevated CO2 responded as expected, with 69% greater photosynthetic rate and 35% larger whole-plant biomass for the first part of the growing season. Contrary to the predictions, however, increased nocturnal temperature had no negative effect on respiration rate or biomass. In fact, plants grown at higher nocturnal temperatures flowered 1.5 d earlier and exhibited a 32% increase in biomass allocation to reproduction. Thus, higher nocturnal temperatures did not diminish the generally positive effects of elevated CO2 on P. americana growth. Instead, these results indicate that elevated CO2 and increasing nocturnal temperatures of the future could have a neutral or even positive effect on P. americana population growth.
CDM potential for rural transition in China case study: Options in Yinzhou district, Zhejiang province
Zhao, XS Michaelowa, A
ENERGY POLICY 34:14 1867-1882
This paper aims to examine the potential of the clean development mechanism (CDM) to address energy-related issues during the rural transition process in China, using a case study of quickly urbanizing and industrializing Yinzhou district in coastal Zhejiang province. Yinzhou’s per capita GDP reached US$ 3 100 in 2002, three times China’s average, and is targeted to achieve $10,000 in 2020. We assess the current energy status of Yinzhou, and provide projections of energy consumption and CO2 emissions up to the year 2020. Energy resource shortages and limited possibilities to obtain coal-fired electricity from national grid illustrate the opening gap between energy supply and demand. We find that Yinzhou’s CDM potential is concentrated in efficiency improvement on the demand side. In that context, we suggest to systematically explore the CDM potential in the industrial sector. Projects will have to involve many stakeholders and the necessary local capacity has to be built. These CDM projects can be considered as killing three birds with one stone, namely maintaining continuous economic growth, alleviating local environmental pollution as well as mitigating global climate change. (c) 2005 Elsevier Ltd. All rights reserved.
Participation of Latin America and the Caribbean in the global climatological records, GHCN
Giddings, L Soto, M
INTERCIENCIA 31:9 632-637
It is impossible to overestimate the importance of historical meteorological records for studies of global climate change. Many of these studies are based on data in GHCN, the Global Historical Climatology Network, a meteorological data compilation available over the Internet that is comprised of voluntary contributions from all over the world. Even though the participation of countries is worthy of note, it should also be recognized that their contributions vary in quality and quantity, and especially in being tip to date. Data of many Latin American countries are incomplete and not up to date, which can cause errors in studies based on these data. Tables and figures show the participation of countries. In the name of researchers of climate change, the authors urge the authorities of all countries to change their policies so that their contributions’ to GHCN will be more complete and up to date.
The connection between the climate change model and a building’s thermal response model: A case of Slovenia
Vidrih, B Dolinar, M Medved, S
STROJNISKI VESTNIK-JOURNAL OF MECHANICAL ENGINEERING 52:9 568-586
The world’s leading climatologists believe that global climate changes are inevitable. The basis for this is the fact that we are already facing climate changes that will become even more significant in the future. The impact of climate changes is and will be noticeable in all fields of human activity; therefore, it will also influence the supply and demand of energy. Since we are observing a longer period of time, comparable to the lifespan of a building, and the amount of energy demanded is an important factor it is necessary to adjust the building and the renovation of buildings to the predicted climate changes. The prediction of a building’s thermal response is the basis for the integral planning of the building and building services installation with which we create suitable living conditions. In order to predict the expected changes in the building’s thermal response in the future it is necessary to correct the available meteorological variable databases today. In this paper we present various climate-change scenaria expected for Slovenia and the methods for correcting the starting points of the local meteorological databases. For the correction we used simplified mathematical models with which we-by forming test reference years (TRYs)-elaborate corrected test reference years (CTRYs). The latter are used for declaring the changes in energy demand in buildings and the effectiveness of a chosen building services installation that uses natural energy sources. As regards the predicted climate scenaria for the continental part of Slovenia, the energy use for heating buildings will be reduced by 1.5% to 31.4%. These climate changes will have a substantial influence on the thermal comfort in buildings during the summer In the heavyweight and naturally ventilated residential buildings that are currently thermally comfortable, suitable summer temperatures will be exceeded during 20% to 33% of the summer The effectiveness of natural and passive cooling techniques will radically change. In cooled buildings we can expect a 2-to-40-fold increase in the use of final (end-use) cooling energy when compared to today. The results presented in this paper confirm the fact that it is necessary to evaluate the consequences of global climate changes also from the point of view of energy use in buildings, their construction and building services installations. (c) 2006 Journal of Mechanical Engineering. All rights reserved.