The Difference between Stated and Measured Travel Data and Their Impact on Environmental Valuation by Travel Cost Method

The main purpose of this study is to assess the reliability of the respondent’s own estimation of the travel distance as a base for calculating travel costs. In order to attain this objective, we have compared the respondent’s stated distances with that of the measured ones, by using environmental valuation survey data conducted on Huis Ten Bosch (HTB). As evaluation tools, scattered diagram plotting, correlation analysis and t-tests of the differences between two means have been used. The findings of the study suggests that, measured distance data might be used for travel costs calculation, as the stated distances are prone to be distorted as the distance from respondent’s residence to the recreational site increases. On the other hand, the significance of the stated distance data should not be disregarded in TCM studies, as it reflects the length of distance felt by the respondents and would provide an important base for estimating recreational benefits

Land Cover Change of Nagasaki City Associated with Natural Disasters by Using Remote Sensing Techniques

Natural disasters are inevitable and it is almost impossible to fully recover the damage caused by the disasters. However, it is possible to reduce the potential risk by developing disaster early warning strategies and to help in rehabilitation and post disaster reduction. Remote sensing technology has efficiently proven its usefulness, not only monitoring the disastrous events, but also to provide accurate and timely information well before the occurrence of disaster. This paper describes an analysis of land cover changes between 1986 and 2000, that have occurred in Nagasaki City over the past few decades. For this purpose, Nagasaki City was studied using Thematic Mapper (TM) data acquired by Landsat-5. Common and reputable unsupervised classification method, Iterative Self-Organizing Data Analysis Technique (ISODATA) is used. From the over all result of study area, it is visible that regelated area is decreasing and urban land is increasing. This trend is especially clear in detailed analysis of typically developed areas as Tagonoura, Koebaru and Kaminoshima

Anthropogenic contributions to slow warming over 1998-2012

The observed global mean surface temperature increase from 1998 to 2012 was slower than that since 1951. The relative contributions of all relevant factors including climate forcers, however, have not been comprehensively analyzed. Using a reduced-complexity climate model and an observationally constrained statistical model, we find that La Nina cooling and a descending solar cycle contributed approximately 50% and 26% of the total warming slowdown during 1998-2012 compared to 1951-2012. Furthermore, reduced ozone-depleting substances and methane accounted for roughly a quarter of the total warming slowdown, which can be explained by changes in atmospheric concentrations. We identify that human factors played an important role in slowing global warming during 1998-2012, shedding light on the evidence for controlling global warming by reducing greenhouse gas emissions.Comment: 55 pages, 26 figures, 4 table

Carbon-concentration and carbon-climate feedbacks in CMIP6 models, and their comparison to CMIP5 models

Abstract. Results from the fully-, biogeochemically-, and radiatively-coupled simulations in which CO2 increases at a rate of 1 % per year (1pctCO2) from its pre-industrial value are analyzed to quantify the magnitude of two feedback parameters which characterize the coupled carbon-climate system. These feedback parameters quantify the response of ocean and terrestrial carbon pools to changes in atmospheric CO2 concentration and the resulting change in global climate. The results are based on eight comprehensive Earth system models from the fifth Coupled Model Intercomparison Project (CMIP5) and eleven models from the sixth CMIP (CMIP6). The comparison of model results from two CMIP phases shows that, for both land and ocean, the model mean values of the feedback parameters and their multi-model spread has not changed significantly across the two CMIP phases. The absolute values of feedback parameters are lower for land with models that include a representation of nitrogen cycle. The sensitivity of feedback parameters to the three different ways in which they may be calculated is shown and, consistent with existing studies, the most relevant definition is that calculated using results from the fully- and biogeochemically-coupled configurations. Based on these two simulations simplified expressions for the feedback parameters are obtained when the small temperature change in the biogeochemically-coupled simulation is ignored. Decomposition of the terms of these simplified expressions for the feedback parameters allows identification of the reasons for differing responses among ocean and land carbon cycle models. </jats:p

Long-term climate change commitment and reversibility: an EMIC intercomparison

This paper summarizes the results of an intercomparison project with Earth System Models of Intermediate Complexity (EMICs) undertaken in support of the Intergovernmental Panel on Climate Change (IPCC) Fifth Assessment Report (AR5). The focus is on long-term climate projections designed to: (i) quantify the climate change commitment of different radiative forcing trajectories, and (ii) explore the extent to which climate change is reversible on human timescales. All commitment simulations follow the four Representative Concentration Pathways (RCPs) and their extensions to 2300. Most EMICs simulate substantial surface air temperature and thermosteric sea level rise commitment following stabilization of the atmospheric composition at year-2300 levels. The meridional overturning circulation (MOC) is weakened temporarily and recovers to near pre-industrial values in most models for RCPs 2.6–6.0. The MOC weakening is more persistent for RCP 8.5. Elimination of anthropogenic CO2 emissions after 2300 results in slowly decreasing atmospheric CO2 concentrations. At year 3000 atmospheric CO2 is still at more than half its year-2300 level in all EMICs for RCPs 4.5–8.5. Surface air temperature remains constant or decreases slightly and thermosteric sea level rise continues for centuries after elimination of CO2 emissions in all EMICs. Restoration of atmospheric CO2 from RCP to pre-industrial levels over 100–1000 years requires large artificial removal of CO2 from the atmosphere and does not result in the simultaneous return to pre-industrial climate conditions, as surface air temperature and sea level response exhibit a substantial time lag relative to atmospheric CO2

Carbon-concentration and carbon-climate feedbacks in CMIP6 models, and their comparison to CMIP5 models

Abstract. Results from the fully-, biogeochemically-, and radiatively-coupled simulations in which CO2 increases at a rate of 1 % per year (1pctCO2) from its pre-industrial value are analyzed to quantify the magnitude of two feedback parameters which characterize the coupled carbon-climate system. These feedback parameters quantify the response of ocean and terrestrial carbon pools to changes in atmospheric CO2 concentration and the resulting change in global climate. The results are based on eight comprehensive Earth system models from the fifth Coupled Model Intercomparison Project (CMIP5) and eleven models from the sixth CMIP (CMIP6). The comparison of model results from two CMIP phases shows that, for both land and ocean, the model mean values of the feedback parameters and their multi-model spread has not changed significantly across the two CMIP phases. The absolute values of feedback parameters are lower for land with models that include a representation of nitrogen cycle. The sensitivity of feedback parameters to the three different ways in which they may be calculated is shown and, consistent with existing studies, the most relevant definition is that calculated using results from the fully- and biogeochemically-coupled configurations. Based on these two simulations simplified expressions for the feedback parameters are obtained when the small temperature change in the biogeochemically-coupled simulation is ignored. Decomposition of the terms of these simplified expressions for the feedback parameters allows identification of the reasons for differing responses among ocean and land carbon cycle models. </jats:p