Mr. Castles and Mr. Henderson have criticized the Special Report on Emissions Scenarios (SRES) and other aspects of IPCC assessments. It is claimed that the methodology is “technically unsound” because market exchange rates (MER) are used instead of purchasing power parities (PPP) and that the scenarios themselves are flawed because the GDP growth in the developing regions is too high. The response is: The IPCC SRES reviews existing literature, most of which is MER based, including that from the World Bank, IEA and USDoE. Scenarios of GDP growth are typically expressed as MER (the preferred measure for GDP growth, as opposed to PPP which is a preferred measure for assessing differences in economic welfare). IPCC scenarios did include PPP-based scenarios, which Mr. Castles and Mr. Henderson have conveniently ignored. Contrary to what Mr. Castles and Mr. Henderson claim, IPCC scenarios are consistent with historical data, including that from 1990 to 2000, and with the most recent near term (up to 2020) projections of other agencies. Long-term emissions are based on multiple, interdependent driving forces, and not just economic growth. Mr. Castles and Mr. Henderson need to look beyond GDP. The IPCC scenarios provided information for only four world regions, and not for specific countries. Mr. Castles' and Mr. Henderson's critique is not of IPCC scenarios but of ongoing unpublished work in progress that is not part of SRES. We therefore show that Mr. Castles and Mr. Henderson have focused on constructing a “problem” that does not exist. SRES scenarios are sound and the IPCC has responded seriously and conscientiously. We detail our response below in nine sections. After an introduction (Section 1), we outline the SRES methodology for measuring economic output (Section 2). Section 3 compares SRES to long-historical economic development and provides five responses to the critics. Section 4 addresses the issue of country-level economic projections even if not part of SRES. Sections 5, 6 and 7 validate the SRES scenarios by comparing them with recent trends for economic and CO2 emission growth, as well as more recent scenarios available in the literature. Section 8 refutes the argument that lower economic growth in developing countries would lower GHG emissions correspondingly. Section 9 concludes.
The atmospheric composition, temperature and sea level implications out to 2300 of new reference and cost-optimized stabilization emissions scenarios produced using three different Integrated Assessment (IA) models are described and assessed. Stabilization is defined in terms of radiative forcing targets for the sum of gases potentially controlled under the Kyoto Protocol. For the most stringent stabilization case ("Level 1" with CO 2 concentration stabilizing at about 450 ppm), peak CO 2 emissions occur close to today, implying (in the absence of a substantial CO 2 concentration overshoot) a need for immediate CO 2 emissions abatement if we wish to stabilize at this level. In the extended reference case, CO 2 stabilizes at about 1,000 ppm in 2200-but even to achieve this target requires large and rapid CO 2 emissions reductions over the twenty-second century. Future temperature changes for the Level 1 stabilization case differ noticeably between the IA models even when a common set of climate model parameters is used (largely a result of different assumptions for non-Kyoto gases). For the Level 1 stabilization case, there is a probability of approximately 50% that warming from pre-industrial times will be Electronic supplementary material The online version of this article (86 Climatic Change (2009) 97:85-121less than (or more than) 2 • C. For one of the IA models, warming in the Level 1 case is actually greater out to 2040 than in the reference case due to the effect of decreasing SO 2 emissions that occur as a side effect of the policy-driven reduction in CO 2 emissions. This effect is less noticeable for the other stabilization cases, but still leads to policies having virtually no effect on global-mean temperatures out to around 2060. Sea level rise uncertainties are very large. For example, for the Level 1 stabilization case, increases range from 8 to 120 cm for changes over 2000 to 2300.
The MiniCAM is a long-term, partial-equilibrium model designed to examine long-term, largescale changes in global and regional energy system where the characteristics of existing capital stocks are not the dominant factor in determining the dynamics of the energy system. Markets are defined for oil (conventional and unconventional), gas, coal, biomass, carbon, and agricultural products. The MiniCAM has no markets for labor and capital. It is specifically designed to address issues associated with global change, including (1) projecting baseline carbon dioxide emissions over time for a country or group of countries; (2) projecting various other radiatively important gases (e.g., methane, nitrous oxide, sulfur dioxide, reactive gases); (3) evaluating the energy-system, emissions, and other consequences of various technological options; (4) evaluating some aspects of potential climate change, e.g., temperature change, sea-level rise; (5) providing a measure of the carbon price, in dollars per metric ton for an emissions target; and (6) providing a measure of the overall cost of meeting an emissions target.The MiniCAM model can be conceptualized as consisting of four modules (see Figure below). • atmospheric composition and global-mean climate changes using the Model for the Assessment of Greenhouse-gas Induced Climate Change (MAGICC) (Hulme and Raper 1993; Wigley 1994a,b;Wigley and Raper 1987, 1993 The MiniCAM has a strong focus on energy supply technologies. A wide range of technologies, fuels, and energy carriers can be used to supply end-use energy demands. Transformation losses are accounted for throughout the supply system. Technologies include electricity generation (from coal, oil, gas, biomass, hydro power, fuel cells, nuclear energy, wind energy, solar PV, solar-wind storage, and space solar PV), hydrogen production (from coal, oil, gas, biomass, and electrolysis), synthetic fuel production (synthetic liquids from coal, gas, and biomass; synthetic gas from coal, and biomass), geologic carbon sequestration from fossil fuels (during electricity generation, hydrogen production, and synthetic fuel production). Biomass supply includes "waste" biomass streams and commercial biomass produced regionally by the AgLU module. End-use fuels include those currently in widespread use (coal, oil, gas, biomass, electricity), and future options such as synthetic liquids, synthetic gases and hydrogen. Carbon sequestration is an option for all conversion technologies, particularly electric generation and hydrogen production. Human activities ERBThe MiniCAM contains a large set of parameters to simulate technical change over time. These parameters include the rate of change in efficiency of inputs to any particular production sector in the model (e.g., primary energy transformation to secondary energy; secondary energy transformation to tertiary energy). These rates of change in input efficiency can be varied at each 15-year time step. The conceptual framework of the ERB and AgLU modules is shown in the figure above. Each pr...
The authors modeled the possible consequences for US cataract incidence of increases in ultraviolet B radiation due to ozone depletion. Data on the dose-response relation between ocular exposure to ultraviolet B radiation and cortical cataract were derived from a population-based study (the Salisbury Eye Evaluation Project, Salisbury, Maryland) in which extensive data on cataract and ultraviolet radiation were collected in persons aged 65-84 years. Exposure estimates for the US population were derived using estimated ultraviolet radiation fluxes as a function of wavelength. US Census data were used to obtain the age, ethnicity, and sex distribution of the population. Predicted probabilities of cataract were derived from the age-, sex-, and ethnicity-specific ocular ultraviolet exposure data and were modeled under conditions of 5-20% ozone depletion. The analysis indicated that by 2050, the prevalence of cortical cataract will increase above expected levels by 1.3-6.9%. The authors estimate that with 5-20% ozone depletion, there will be 167,000-830,000 additional cases of cortical cataract by 2050. Because of the high prevalence of cataract in older persons, at a 2003 cost of 3,370 dollars per cataract operation, this increase could represent an excess cost of 563 million dollars to 2.8 billion dollars.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.