Climate — Open Access Journal of Climate Science
Climate (ISSN 2225-1154; CODEN: CLIMC9) is a scientific peer-reviewed open access journal of climate science published online quarterly by MDPI.
- Open Access - free for readers, with article processing charges (APC) paid by authors or their institutions.
- High visibility: Indexed in the Emerging Sources Citation Index (ESCI - Web of Science) and other databases. Covered in Scopus from Vol. 5 (2017).
- Rapid publication: manuscripts are peer-reviewed and a first decision provided to authors approximately 17 days after submission; acceptance to publication is undertaken in 4.95 days (median values for papers published in the first six months of 2018).
- Recognition of Reviewers: reviewers who provide timely, thorough peer-review reports receive vouchers entitling them to a discount on the APC of their next publication in any MDPI journal, in appreciation of the work done.
Leftover Spaces for the Mitigation of Urban Overheating in Municipal Beirut►▼ Figures
Climate 2018, 6(3), 68; https://doi.org/10.3390/cli6030068 (registering DOI) - 21 August 2018
The Urban Heat Island phenomenon and urban overheating are serious consequences of urbanization resulting in impacts on thermal comfort levels, heat stress and even mortality. This paper builds on previous findings on the topic of non-constructible parcels, small vacant or built spaces in[...] Read more.
The Urban Heat Island phenomenon and urban overheating are serious consequences of urbanization resulting in impacts on thermal comfort levels, heat stress and even mortality. This paper builds on previous findings on the topic of non-constructible parcels, small vacant or built spaces in Municipal Beirut, some of which belong to the municipality while others are privately owned and which might be used for different functional purposes. This paper further examines the possibility of implementing cool surface or paving materials and urban vegetation to reduce air urban temperature, especially during the summer period and with the view to project the positive findings of this case study to the entire Municipal Beirut area. A numerical analysis using ENVI-met 4.0 investigates the thermal performance of these non-constructibles further to implementation of high reflective surfaces and urban vegetation on a broad neighborhood scale, taking the Bachoura District as a reference case for a typical summer day. The best air temperature reductions correspond to the use of cool material in areas that are far from buildings where there are no shadow effects. In some cases, the introduction of trees leads to an increase of the air temperature near the ground because they became an obstacle of the natural ventilation. Results show a maximum mitigation effect with the use of cool materials that lead to reductions in air temperatures up to 0.42 °C if used alone and up to 0.77 °C if used in combination with trees. Within the framework of an integrated approach to planning, this form of urban intervention aims for substantial overheating reduction. Full article
Multihazard Risk Assessment for Planning with Climate in the Dosso Region, Niger►▼ Figures
Climate 2018, 6(3), 67; https://doi.org/10.3390/cli6030067 - 8 August 2018
International aid for climate change adaptation in West Africa is increasing exponentially, but our understanding of hydroclimatic risks is not keeping pace with that increase. The aim of this article is to develop a multihazard risk assessment on a regional scale based on[...] Read more.
International aid for climate change adaptation in West Africa is increasing exponentially, but our understanding of hydroclimatic risks is not keeping pace with that increase. The aim of this article is to develop a multihazard risk assessment on a regional scale based on existing information that can be repeated over time and space and that will be useful during decision-making processes. This assessment was conducted in Dosso (Niger), the region most hit by flooding in the country, with the highest hydroclimatic risk in West Africa. The assessment characterizes the climate, identifies hazards, and analyzes multihazard risk over the 2011–2017 period for each of the region’s 43 municipalities. Hazards and risk level are compared to the intervention areas and actions of 6 municipal development plans and 12 adaptation and resilience projects. Over the past seven years, heavy precipitation and dry spells in the Dosso region have been more frequent than during the previous 30-year period. As many as 606 settlements have been repeatedly hit and 15 municipalities are classified as being at elevated-to-severe multihazard risk. The geographical distribution of the adaptation and resilience projects does not reflect the risk level. A third of the local development plans examined propose actions that are inconsistent with the main hydroclimatic threats. Full article
Changes in the Intensity and Variability of Precipitation in the Central Region of Argentina between 1960 and 2012►▼ Figures
Climate 2018, 6(3), 66; https://doi.org/10.3390/cli6030066 - 25 July 2018
This study analyzes the temporal variation of different rainfall features in the central region of Argentina between 1960 and 2012, and evaluates the dynamics of temporal trends by using the Mann–Kendall–Sneyers (MKS) and Tomé–Miranda (TM) procedures. Under different criteria and levels of significance,[...] Read more.
This study analyzes the temporal variation of different rainfall features in the central region of Argentina between 1960 and 2012, and evaluates the dynamics of temporal trends by using the Mann–Kendall–Sneyers (MKS) and Tomé–Miranda (TM) procedures. Under different criteria and levels of significance, rainfall time series show homogeneous behavior in more than 80% of cases. Only 18 of the 42 annual cases analyzed reached a significant long-term trend (p < 0.10). Total annual rainfall (AR) showed a significant increase only in Laboulaye Aero (LB) and Villa Dolores Aero (VD), but this does not currently persist. A decrease in the annual frequency of rainy days (DPF) is more widespread in the region. Thus, the increase in mean annual rainfall intensity (INT) seems to be particularly associated with the decrease in annual frequency of events (DPF) in the central region of Argentina. However, the increase in INT currently persists only at the Córdoba Observatorio (BO), as INT stopped growing for LB, Río Cuarto Aero (RC), and VD in the mid-1990s. The variation coefficients of total annual rainfall (ARCV) and DPF (DPFCV) have increased in the region, but with the former restricted locally to the Pilar Observatorio (PI), RC, and VM, and the latter to BO and RC. Long-term changes of the pluvial regime in the central region of Argentina appear to be not only local and restricted to some properties of rainfall during the period, but also reveal a particular dynamic where the long-term trends of the evaluated properties have now changed sign or maintain a certain constancy at present. Full article
Farmers’ Net Income Distribution and Regional Vulnerability to Climate Change: An Empirical Study of Bangladesh►▼ Figures
Climate 2018, 6(3), 65; https://doi.org/10.3390/cli6030065 - 23 July 2018
Widespread poverty is the most serious threat and social problem that Bangladesh faces. Regional vulnerability to climate change threatens to escalate the magnitude of poverty. It is essential that poverty projections be estimated while bearing in mind the effects of climate change. The[...] Read more.
Widespread poverty is the most serious threat and social problem that Bangladesh faces. Regional vulnerability to climate change threatens to escalate the magnitude of poverty. It is essential that poverty projections be estimated while bearing in mind the effects of climate change. The main purpose of this paper is to perform an agrarian sub-national regional analysis of climate change vulnerability in Bangladesh under various climate change scenarios and evaluate its potential impact on poverty. This study is relevant to socio-economic research on climate change vulnerability and agriculture risk management and has the potential to contribute new insights to the complex interactions between household income and climate change risks to agricultural communities in Bangladesh and South Asia. This study uses analysis of variance, cluster analysis, decomposition of variance and log-normal distribution to estimate the parameters of income variability that can be used to ascertain vulnerability levels and help us to understand the poverty levels that climate change could potentially generate. It is found that the levels and sources of income vary greatly among regions of Bangladesh. The variance decomposition of income showed that agricultural income in Mymensingh and Rangpur is the main cause of the total income difference among all sources of income. Moreover, a large variance in agricultural income among regions is induced by the gross income from rice production. Additionally, even in the long run the gradual, constant reduction of rice yield due to climate change in Bangladesh is not a severe problem for farmers. However, extreme events such as floods, flash floods, droughts, sea level rise and greenhouse gas emissions, based on Representative concentration pathways (RCPs), could increase the poverty rates in Mymensingh, Rajshahi, Barisal and Khulna—regions that would be greatly affected by unexpected yield losses due to extreme climatic events. Therefore, research into and development of adaptation measures to climate change in regions where farmers are largely dependent on agricultural income are important. Full article
The Life and Death of the Recent Global Surface Warming Hiatus Parsimoniously Explained►▼ Figures
Climate 2018, 6(3), 64; https://doi.org/10.3390/cli6030064 - 21 July 2018
The main features of the instrumental global mean surface temperature (GMST) are reasonably well described by a simple linear response model driven by anthropogenic, volcanic and solar forcing. This model acts as a linear long-memory filter of the forcing signal. The physical interpretation[...] Read more.
The main features of the instrumental global mean surface temperature (GMST) are reasonably well described by a simple linear response model driven by anthropogenic, volcanic and solar forcing. This model acts as a linear long-memory filter of the forcing signal. The physical interpretation of this filtering is the delayed response due to the thermal inertia of the ocean. This description is considerably more accurate if El Niño Southern Oscillation (ENSO) and the Atlantic Multidecadal Oscillation (AMO) are regarded as additional forcings of the global temperature and hence subject to the same filtering as the other forcing components. By considering these as predictors in a linear regression scheme, more than 92% of the variance in the instrumental GMST over the period 1870–2017 is explained by this model, in particular, all features of the 1998–2015 hiatus, including its death. While the more prominent pauses during 1870–1915 and 1940–1970 can be attributed to clustering in time of strong volcanic eruptions, the recent hiatus is an unremarkable phenomenon that is attributed to ENSO with a small contribution from solar activity. Full article
Mapping Precipitation, Temperature, and Evapotranspiration in the Mkomazi River Basin, Tanzania►▼ Figures
Climate 2018, 6(3), 63; https://doi.org/10.3390/cli6030063 - 17 July 2018
It is still a challenge to provide spatially explicit predictions of climate parameters in African regions of complex relief, where meteorological information is scarce. Here we predict rainfall, temperature, and reference evapotranspiration (ETo) for the southern Mkomazi River Basin in Northeastern[...] Read more.
It is still a challenge to provide spatially explicit predictions of climate parameters in African regions of complex relief, where meteorological information is scarce. Here we predict rainfall, temperature, and reference evapotranspiration (ETo) for the southern Mkomazi River Basin in Northeastern Tanzania, East Africa, by means of regression-based, digital elevation models (DEM) at 90 m spatial-resolution and geographic information systems (GIS) techniques. We mapped rainfall for the period 1964–2010. The models accounted for orographic factors which strongly influenced the spatial variability of rainfall in the region. According to orography, the area was divided into three zones for modelling rainfall: windward, leeward, and transition zone. Rainfall indicates high spatial and temporal variability dominated by equatorial East-African climate circulation systems. Maximum and minimum temperatures were modelled for the period 1989–1994, the models accounted only for the altitude gradient. Mean temperature was calculated by arithmetic mean of maximum and minimum temperatures maps in ArcGIS. ETo was estimated in ArcGIS following the method described by Hargreaves and Samani. The maps were made on a monthly basis for rainfall, ETo, and mean, maximum, and minimum temperatures. The obtained maps are useful for the purpose of agriculture, ecological, and water resources management. Full article
Changes in Earth’s Energy Budget during and after the “Pause” in Global Warming: An Observational Perspective►▼ Figures
Climate 2018, 6(3), 62; https://doi.org/10.3390/cli6030062 - 11 July 2018
This study examines changes in Earth’s energy budget during and after the global warming “pause” (or “hiatus”) using observations from the Clouds and the Earth’s Radiant Energy System. We find a marked 0.83 ± 0.41 Wm−2 reduction in global mean reflected shortwave[...] Read more.
This study examines changes in Earth’s energy budget during and after the global warming “pause” (or “hiatus”) using observations from the Clouds and the Earth’s Radiant Energy System. We find a marked 0.83 ± 0.41 Wm−2 reduction in global mean reflected shortwave (SW) top-of-atmosphere (TOA) flux during the three years following the hiatus that results in an increase in net energy into the climate system. A partial radiative perturbation analysis reveals that decreases in low cloud cover are the primary driver of the decrease in SW TOA flux. The regional distribution of the SW TOA flux changes associated with the decreases in low cloud cover closely matches that of sea-surface temperature warming, which shows a pattern typical of the positive phase of the Pacific Decadal Oscillation. Large reductions in clear-sky SW TOA flux are also found over much of the Pacific and Atlantic Oceans in the northern hemisphere. These are associated with a reduction in aerosol optical depth consistent with stricter pollution controls in China and North America. A simple energy budget framework is used to show that TOA radiation (particularly in the SW) likely played a dominant role in driving the marked increase in temperature tendency during the post-hiatus period. Full article
Ocean Impacts on Australian Interannual to Decadal Precipitation Variability►▼ Figures
Climate 2018, 6(3), 61; https://doi.org/10.3390/cli6030061 - 11 July 2018
In Australia, successful seasonal predictions of wet and dry conditions are achieved by utilizing the remote impact of sea surface temperature (SST) variability in tropical oceans, particularly the Pacific Ocean, on the seasonal timescale. Beyond seasonal timescales, however, it is still unclear which[...] Read more.
In Australia, successful seasonal predictions of wet and dry conditions are achieved by utilizing the remote impact of sea surface temperature (SST) variability in tropical oceans, particularly the Pacific Ocean, on the seasonal timescale. Beyond seasonal timescales, however, it is still unclear which processes and oceans contribute to interannual-to-decadal wet/dry conditions in Australia. This research examines the interannual-to-decadal relationship between global SST anomalies (SSTAs) and Australian wet/dry variability by analyzing observational data and global climate model experiments conducted with the NCAR Community Earth System Model (CESM) and the Model for Interdisciplinary Research on Climate (MIROC). A 10-member ensemble simulation suite for 1960–2015 (CESM) and 1950–2010 (MIROC) is conducted by assimilating the observed three-dimensional ocean temperature and salinity anomalies into fully coupled global climate models. In both observational analyses and ocean assimilation experiments, the most dominant annual mean precipitation variability shows a clear relationship with SSTAs in the tropical Pacific and the Atlantic. Our partial ocean assimilation experiment, in which the ocean component of the CESM and MIROC are assimilated by the observed ocean temperature and salinity anomalies in the equatorial Pacific only, shows that the tropical Pacific SST variability is the main driver of Australian precipitation variability on the interannual-to-decadal timescales. However, our additional partial ocean assimilation experiment, in which the climate models incorporate the observed anomalies solely in the Atlantic ocean, demonstrates that the Atlantic Ocean can also affect Australian precipitation variability on the interannual-to-decadal timescale through changes in tropical Pacific SSTAs and the modulation of the global Walker circulation. Our results suggest that about a half of Australian interannual-to-decadal precipitation variability originates from the Atlantic Ocean. Full article
Sky View Factor Calculation in Urban Context: Computational Performance and Accuracy Analysis of Two Open and Free GIS Tools►▼ Figures
Climate 2018, 6(3), 60; https://doi.org/10.3390/cli6030060 - 4 July 2018
The sky view factor (SVF) has an important role in the analysis of the urban micro-climate. A new vector-based SVF calculation tool was implemented in a free and open source Geographic Information System named OrbisGIS. Its accuracy and computational performance are compared to[...] Read more.
The sky view factor (SVF) has an important role in the analysis of the urban micro-climate. A new vector-based SVF calculation tool was implemented in a free and open source Geographic Information System named OrbisGIS. Its accuracy and computational performance are compared to the ones of an existing raster based algorithm used in SAGA-GIS. The study is performed on 72 urban blocks selected within the Paris commune territory. This sample has been chosen to represent the heterogeneity of nine of the ten Local Climate Zone built types. The effect of the algorithms’ input parameters (ray length, number of directions and grid resolution) is investigated. The combination minimizing the computation time and the SVF error is identified for SAGA-GIS and OrbisGIS algorithms. In both cases, the standard deviation of the block mean SVF estimate is about 0.03. A simple linear relationship having a high determination coefficient is also established between block mean SVF and the facade density fraction, confirming the results of previous research. This formula and the optimized combinations for the OrbisGIS and the SAGA-GIS algorithms are finally used to calculate the SVF of every urban block of the Paris commune. Full article
Recent Changes of Floods and Related Impacts in Niger Based on the ANADIA Niger Flood Database►▼ Figures
Climate 2018, 6(3), 59; https://doi.org/10.3390/cli6030059 - 3 July 2018
During the last two decades, the sub-Saharan region has experienced unusual floods that have differentially impacted the region. No official and precise data regarding flood damage and impacts on the population are available, and the magnitude of events are not easily evaluated. Most[...] Read more.
During the last two decades, the sub-Saharan region has experienced unusual floods that have differentially impacted the region. No official and precise data regarding flood damage and impacts on the population are available, and the magnitude of events are not easily evaluated. Most previous studies have investigated this new threat using data derived from local media sources or world disaster databases. The aim of this study was to provide the scientific community and policy makers with an updated and reliable referenced data source concerning floods in Niger between 1998 and 2015, at national, regional and sub-regional scales. Reliable information regarding floods was derived from the national official flood damage database (ANADIA DB) showing their impact on the country. During the investigated period, considerable numbers regarding flood impacts were found (about 4000 settlements and 1.7 million people were affected by floods). The analysis also indicates a sudden increase in flood impacts since 2010. Regions in the south-west (Tillabery, Dosso and Niamey district) are the most affected; however, this kind of risk involves the whole country, and some particularly vulnerable areas have been identified. A data modeling comprehensive framework based on remotely sensed rainfall (climate hazards group infrared precipitation with stations (CHIRPS)) and vegetation index (moderate resolution imagery spectroradiometer normalized difference vegetation index (MODIS NDVI)) datasets data along with census data were used to investigate which variables are most able to explain the recent and sudden Niger flood vulnerability detected at the departmental scale. Only a few statistically significant flood damage models were found (61 out of 297), due essentially to the non-linearity of the increase in damage time series compared to environmental and climatic trends. The population increase is the most significant variable at national level; however, at regional and sub-regional scales, different patterns provided evidence to identify local triggers for vulnerability. Full article
Downscaling of Future Temperature and Precipitation Extremes in Addis Ababa under Climate Change►▼ Figures
Climate 2018, 6(3), 58; https://doi.org/10.3390/cli6030058 - 28 June 2018
One of the recent advances in climate science research is the development of global general circulation models (GCMs) to simulate changes in climatic elements of the present and future, which helps us to determine consequences earlier and prepare for necessary adaptation measures. However,[...] Read more.
One of the recent advances in climate science research is the development of global general circulation models (GCMs) to simulate changes in climatic elements of the present and future, which helps us to determine consequences earlier and prepare for necessary adaptation measures. However, it is difficult to apply the raw data of GCMs at a local scale, such as the urban scale, without downscaling due to coarse resolution. This study, therefore, statistically downscaled daily maximum temperature, minimum temperature, and precipitation in 30-year intervals from the second generation of the Earth System Model (CanESM2) and Coupled Global Climate Model (CGCM3) under two Representative Concentration Pathways (RCP) Scenarios (RCP4.5 and RCP8.5) and two Special Report Emission Scenarios (SRES), A1B and A2, to examine future changes and their extremes. Two representative meteorological stations (Entoto at high elevation and Addis Ababa at downtown and medium elevation) were selected for model calibration and validation in the Statistical Downscaling Model (SDSM). Twelve core temperature and precipitation indices were selected to assess temperature changes and precipitation extremes. For the largest changes the results showed that the maximum temperature increases were in the range of 0.9 °C (RCP4.5) in 2020 to 2.1 °C (CGCM3A2) in 2080 at Addis Ababa Observatory. The minimum temperature is projected to increase by 0.3 °C (RCP4.5) in 2020 and 1.0 °C in 2080 (CGCM3A1B). While the changes in maximum temperature are lower at Entoto station compared to Addis Ababa Observatory, the highest minimum temperature change is projected at Addis Ababa Observatory, which ranges from 0.25 °C in the 2020s to 1.04 °C in 2080 according to the CGCM3 model. Except for the coldest nights (TNn), the mean temperature and other temperature indices will continue to increase to the end of this century. The highest precipitation change is projected by CGCM3A2 and CanESM2 RCP8.5 at an increase of about 11.8% and 16.62% by 2080. The highest total precipitation increase is 29% (RCP4.5) in winter and 20.9% (RCP8.5) in summer by 2080. There is high interseasonal variability in changes of extreme events. The topographic role will diminish in influence on the air temperature distribution due to the high rate of urbanization. The rise in temperature will exacerbate the urban heat highland effects in warm seasons and an increase in precipitation is expected along with a possible risk of flooding due to a low level of infrastructure development and a high rate of urbanization. Full article
Modelling Hydrological Components of the Rio Maipo of Chile, and Their Prospective Evolution under Climate Change►▼ Figures
Climate 2018, 6(3), 57; https://doi.org/10.3390/cli6030057 - 25 June 2018
We used the Poly-Hydro model to assess the main hydrological components of the snow-ice melt driven Maipo River in Chile, and glaciers’ retreat under climate change therein until 2100. We used field data of ice ablation, ice thickness, weather and hydrological data, and[...] Read more.
We used the Poly-Hydro model to assess the main hydrological components of the snow-ice melt driven Maipo River in Chile, and glaciers’ retreat under climate change therein until 2100. We used field data of ice ablation, ice thickness, weather and hydrological data, and precipitation from TRMM. Snow cover and temperature were taken from MODIS. We forced the model using weather projections until 2100 from three GCMs from the IPCC AR5, under three different radiative concentration pathways (RCPs 2.6, 4.5, 8.5). We investigated trends of precipitation, temperature, and hydrology until 2100 in the projection period (PR, 2014–2100) and the whole period (CM 1980–2100, composite), against historical trends in control period (CP, 1980–2013). We found potentially increasing temperature until 2100, except for Spring (OND). In the PR period, yearly flow decreases significantly under RCP85, on average −0.25 m3·s−1·year−1, and down to −0.48 m3·s−1·year−1, i.e., −0.4% year−1 against CP yearly average (120 m3 s−1). In the long run (CM) significant flow decrease would, occur under almost all scenarios, confirming persistence of a historical decrease, down to −0.39 m3·s−1·year−1 during CM. Large flow decreases are expected under all scenarios in Summer (JFM) during PR, down to −1.6 m3·s−1·year−1, or −1% year−1 against CP for RCP8.5, due to increase of evapotranspiration in response to higher temperatures. Fall (AMJ) flows would be mostly unchanged, while Winter (JAS) flows would be projected to increase significantly, up to 0.7 m3·s−1·year−1 during 2014–2100, i.e., +0.9% year−1 vs. CP under RCP8.5, due to large melting therein. Spring (OND) flows would decrease largely under RCP8.5, down to −0.67 m3 s−1·year−1, or −0.4% year−1 vs. CP, again due to evapotranspiration. Glacier down wasting is projected to speed up, and increasingly so with RCPs. Until 2100 ice loss would range from −13% to −49% (−9%, and −39% at 2050) of the estimated volume at 2012, which changed by −24% to −56% (−21%, and −39% at 2050) vs. ice volume in 1982, thus with rapider depletion in the first half of the century. Policy makers will have to cope with modified hydrological cycle in the Maipo River, and greatly decreasing ice cover in the area. Full article
The Effect of Building Facades on Outdoor Microclimate—Reflectance Recovery from Terrestrial Multispectral Images Using a Robust Empirical Line Method►▼ Figures
Climate 2018, 6(3), 56; https://doi.org/10.3390/cli6030056 - 25 June 2018
Climate change and the urban heat island effect pose significant health, energy and economic risks. Urban heat mitigation research promotes the use of reflective surfaces to counteract the negative effects of extreme heat. Surface reflectance is a key parameter for understanding, modeling and[...] Read more.
Climate change and the urban heat island effect pose significant health, energy and economic risks. Urban heat mitigation research promotes the use of reflective surfaces to counteract the negative effects of extreme heat. Surface reflectance is a key parameter for understanding, modeling and modifying the urban surface energy balance to cool cities and improve outdoor thermal comfort. The majority of urban surface studies address the impacts of horizontal surface properties at the material and precinct scales. However, there is a gap in research focusing on individual building facades. This paper analyses the results of a novel application of the empirical line method to calibrate a terrestrial low-cost multispectral sensor to recover spectral reflectance from urban vertical surfaces. The high correlation between measured and predicted mean reflectance values per waveband (0.940 (Red) < rs > 0.967 (NIR)) confirmed a near-perfect positive agreement between pairs of samples of ranked scores. The measured and predicted distributions exhibited no statistically significant difference at the 95% confidence level. Accuracy measures indicate absolute errors within previously reported limits and support the utility of a single-target spectral reflectance recovery method for urban heat mitigation studies focusing on individual building facades. Full article
Evaluation and Modeling of Urban Heat Island Intensity in Basel, Switzerland►▼ Figures
Climate 2018, 6(3), 55; https://doi.org/10.3390/cli6030055 - 21 June 2018
An increasing number of people living in urban environments and the expected increase in long lasting heat waves makes the study of temperature distribution one of the major tasks in urban climatology, especially considering human health and heat stress. This excess heat is[...] Read more.
An increasing number of people living in urban environments and the expected increase in long lasting heat waves makes the study of temperature distribution one of the major tasks in urban climatology, especially considering human health and heat stress. This excess heat is often underestimated because stations from national meteorological services are limited in numbers and are not representing the entire urban area with typically higher nocturnal temperatures, especially in densely built-up environments. For a majority of the population, heat stress is consequently monitored insufficiently. In this study, the factors influencing the nocturnal urban heat island have been evaluated in detail and have been tested using different spatial resolutions. A multiple linear regression model has been developed with predictors resulting from different data sources to model the urban air temperature distribution continuously. Results show that various datasets can be used for the prediction of the heat island distribution with comparable results, ideally run on a 200 m grid. Validation using random sampling indicated a RMSE clearly below the standard deviation of the measurements with an average around ~0.15 °C. The regression coefficients are varying within the nocturnal runs with best results around 22:00 CET (R2 > 0.9). Full article
Livestock Under Climate Change: A Systematic Review of Impacts and Adaptation►▼ Figures
Climate 2018, 6(3), 54; https://doi.org/10.3390/cli6030054 - 21 June 2018
We conducted a systematic literature review to document the scientific knowledge about climate change impacts and adaptation in livestock systems, and to identify research gaps. The analysis was built from the premise that livestock offers substantial opportunities for food security and sustainable development[...] Read more.
We conducted a systematic literature review to document the scientific knowledge about climate change impacts and adaptation in livestock systems, and to identify research gaps. The analysis was built from the premise that livestock offers substantial opportunities for food security and sustainable development if adaptation to climate change is appropriated. In examining 126 suitable peer-reviewed publications we discovered five research gaps: (1) a lack of research in Asia and South America; (2) a lack of mutual investigation and linkages between impacts and adaptation; (3) a lack of emphasis on mixed crop-livestock systems; (4) a lack of emphasis on monogastric livestock; and (5) an underrepresentation of quantitative methods including yield impact models. The findings suggest that the research on climate change impacts and adaptation in livestock systems needs to move beyond certain geographical contexts and consider key vulnerability priorities, particularly from developing countries. It is pivotal that research begins to jointly look at climate change impacts and the livestock keepers’ adaptation to draw out policy implications and to effectively target support for impact-specific adaptation options. Only if such evidence is established, adaptation will be appropriated accordingly to the needs of the livestock sector, and provision for the growing demand of animal-based products will be secured. Full article
Air-Temperature Response to Neighborhood-Scale Variations in Albedo and Canopy Cover in the Real World: Fine-Resolution Meteorological Modeling and Mobile Temperature Observations in the Los Angeles Climate Archipelago►▼ Figures
Climate 2018, 6(2), 53; https://doi.org/10.3390/cli6020053 - 17 June 2018
To identify and characterize localized urban heat- and cool-island signals embedded within the temperature field of a large urban-climate archipelago, fine-resolution simulations with a modified urbanized version of the WRF meteorological model were carried out as basis for siting fixed weather monitors and[...] Read more.
To identify and characterize localized urban heat- and cool-island signals embedded within the temperature field of a large urban-climate archipelago, fine-resolution simulations with a modified urbanized version of the WRF meteorological model were carried out as basis for siting fixed weather monitors and designing mobile-observation transects. The goal was to characterize variations in urban heat during summer in Los Angeles, California. Air temperatures measured with a shielded sensor mounted atop an automobile in the summers of 2016 and 2017 were compared to model output and also correlated to surface physical properties focusing on neighborhood-scale albedo and vegetation canopy cover. The study modeled and measured the temperature response to variations in surface properties that already exist in the real world, i.e., realistic variations in albedo and canopy cover that are attainable through current building and urban design practices. The simulated along-transect temperature from a modified urbanized WRF model was compared to the along-transect observed temperature from 15 mobile traverses in one area near downtown Los Angeles and another in an inland basin (San Fernando Valley). The observed transect temperature was also correlated to surface physical properties characterizations that were developed for input to the model. Both comparisons were favorable, suggesting that (1) the model can reliably be used in siting fixed weather stations and designing mobile-transect routes to characterize urban heat and (2) that except for a few cases with opposite co-varying influences, the correlations between observed temperature and albedo and between observed temperature and canopy cover were each negative, ranging from −1.0 to −9.0 °C per 0.1 increase in albedo and from −0.1 to −2.2 °C per 0.1 increase in canopy cover. Observational data from the analysis domains pointed to a wind speed threshold of 3 m/s. Below this threshold the variations in air temperature could be explained by land use and surface properties within a 500-m radius of each observation point. Above the threshold, air temperature was influenced by the properties of the surface within a 1-km upwind fetch. Of relevance to policy recommendations, the study demonstrates the significant real-world cooling effects of increasing urban albedo and vegetation canopy cover. Based on correlations between the observed temperature (from mobile transects) and surface physical properties in the study domains, the analysis shows that neighborhood-scale (500-m) cooling of up to 2.8 °C during the daytime can be achieved by increasing albedo. A neighborhood can also be cooled by up to 2.3 °C during the day and up to 3.3 °C at night by increasing canopy cover. The analysis also demonstrates the suitability of using fine-resolution meteorological models to design mobile-transect routes or site-fixed weather monitors in order to quantify urban heat and the efficacy of albedo and canopy cover countermeasures. The results also show that the model is capable of accurately predicting the geographical locations and the magnitudes of localized urban heat and cool islands. Thus the model results can also be used to devise urban-heat mitigation measures. Full article
A New Radiative Model Derived from Solar Insolation, Albedo, and Bulk Atmospheric Emissivity: Application to Earth and Other Planets►▼ Figures
Climate 2018, 6(2), 52; https://doi.org/10.3390/cli6020052 - 14 June 2018
This study develops an equilibrium radiative model based on a quasi-adiabatic atmosphere that quantifies the average surface flux of a planetary body as a function of absorbed solar radiation P and the bulk emissivity of the atmosphere with respect to surface radiation[...] Read more.
This study develops an equilibrium radiative model based on a quasi-adiabatic atmosphere that quantifies the average surface flux of a planetary body as a function of absorbed solar radiation P and the bulk emissivity of the atmosphere with respect to surface radiation
. The surface flux is then given by , and I define the scaling term as the greenhouse factor. The model is applied to all of the rocky planets in the solar system to determine their greenhouse factors, and accounts for the diversity of planetary surface fluxes. The model is modified to allow for a top of atmosphere non-equilibrium state, which when compared with a recent observation-based model of the Earth energy budget, predicts the Earth’s radiative fluxes to within the uncertainty ranges of that model. The model developed in this study is able to quantify the changes in Earth’s surface flux caused by changes in bond albedo and atmospheric bulk emissivity by using the surface temperature, ocean heat content, incoming solar radiation and outgoing longwave radiation records. The model indicates an increase in absorbed solar radiation over the time period from 1979–2015 of the order of 3 W/m2, which was caused by a decrease in planetary bond albedo. The time-series albedo generated by the model is in agreement with Clouds and Earth’s Radiant Energy System (CERES) derived albedo over the period from 2000–2015. The model also indicates a slight decrease in atmospheric bulk emissivity over the same period. Since atmospheric bulk emissivity is a function of the sum of all of the greenhouse gas species, a simultaneous decrease in atmospheric water vapor may offset the effect of the well-documented increase in the non-condensing greenhouse gases over the period, and result in an overall net decrease in bulk emissivity. Atmospheric water vapor datasets partially support the conclusion, with the International Satellite Cloud Climatology Project (ISCCP) data supporting a decrease. The NASA Water Vapor Project (NVAP-M) data supports a decrease in atmospheric water content over the period 1998–2008, but not over the longer period of 1988–2008. The model indicates that the decrease in planetary albedo was the driver for the increased surface flux over the stated period.
Multi-Decadal Trend and Decadal Variability of the Regional Sea Level over the Indian Ocean since the 1960s: Roles of Climate Modes and External Forcing►▼ Figures
Climate 2018, 6(2), 51; https://doi.org/10.3390/cli6020051 - 8 June 2018
Previous studies suggest that anthropogenic warming has affected the multi-decadal trend patterns of sea level over the Indian Ocean (IO). This effect, however, has not been quantified. Using observational datasets combined with large ensemble experiments from two climate models, this paper assesses the[...] Read more.
Previous studies suggest that anthropogenic warming has affected the multi-decadal trend patterns of sea level over the Indian Ocean (IO). This effect, however, has not been quantified. Using observational datasets combined with large ensemble experiments from two climate models, this paper assesses the effects of natural internal variability versus external forcing on the observed, multi-decadal trend pattern and the decadal sea level anomaly (SLA) of the IO since the 1960s. Because the global mean sea level rise (SLR), which results largely from external forcing, has been removed before the examination, the paper focuses on the regionally uneven distribution of trend and SLA. The impacts of climate modes are quantified using a Bayesian Dynamic Linear Model. For the regional trend pattern of 1958–2005, the effects of internal variability dominate external forcing. Over the Seychelles area where sea-level variations obtain the maximum, internal variability (external forcing) contributes 81% (19 ± 2.4%) of the observed trend. For decadal SLA, internal variability is the predominant cause, with a standard deviation (STD) ratio of externally forced/observed SLA being 18 ± 17% over Seychelles and 17 ± 11% near the Indonesian Throughflow (ITF) area. Climate modes account for most observed SLA during boreal winter, with the total effects of decadal ENSO, Indian Ocean Dipole (IOD), and monsoon accounting for 78–86% of the observed STD near the Seychelles region, ITF area, and coasts of Sumatra and the Bay of Bengal. During summer, climate modes explain 95% of observed STD near the ITF but only 58–67% in other regions. Decadal ENSO dominates the SLA in the south tropical IO for both seasons and near the coasts of Sumatra and the Bay during winter. Decadal IOD and monsoon, however, control the coastal SLA during summer. Remote and local winds over the IO are the main drivers for decadal SLA, while the Pacific influence via the ITF is strong mainly in the southeast basin. Full article
Multifractal Analysis of High-Frequency Temperature Time Series in the Urban Environment►▼ Figures
Climate 2018, 6(2), 50; https://doi.org/10.3390/cli6020050 - 8 June 2018
Continuous monitoring systems have been regarded as a very useful tool to provide continuous high-frequency measurements of many parameters. Here, we analyze high-frequency time series of air temperature measurements, recorded every 10 min during 2003 in Athens (Greece) by an online monitoring system[...] Read more.
Continuous monitoring systems have been regarded as a very useful tool to provide continuous high-frequency measurements of many parameters. Here, we analyze high-frequency time series of air temperature measurements, recorded every 10 min during 2003 in Athens (Greece) by an online monitoring system for the urban environment. We propose a set of time series analysis techniques, where missing data are well respected and information concerning the system’s dynamics is preserved. A power spectral density analysis is performed over time scales spanning from 10 min to several days. A scale-invariant behavior of the form is revealed for scales below 9 h. Over this scaling range, we have performed structure functions analysis, and shown that air temperature data exhibit turbulent-like intermittent properties with multi-fractal statistics. The multifractal exponents obtained possess some similarities with passive scalar turbulence results. Although we illustrate the proposed approach using air temperature data, the method can be used as an efficient tool to analyse other environmental parameters monitored in urban environment. Full article
An Empirical Comparison of Carbon Credit Projects under the Clean Development Mechanism and Verified Carbon Standard►▼ Figures
Climate 2018, 6(2), 49; https://doi.org/10.3390/cli6020049 - 4 June 2018
Carbon credit projects generate carbon credits by abating greenhouse gas emissions. Carbon credits can then be traded on carbon markets or immobilized in order to compensate for caused emissions. The Clean Development Mechanism (CDM) and Verified Carbon Standard (VCS), as the two most[...] Read more.
Carbon credit projects generate carbon credits by abating greenhouse gas emissions. Carbon credits can then be traded on carbon markets or immobilized in order to compensate for caused emissions. The Clean Development Mechanism (CDM) and Verified Carbon Standard (VCS), as the two most important carbon credit mechanisms, are investigated and compared regarding the success of projects. We define success as the fulfilling of the ex-ante emission abatement estimation and apply regression analyses to explain its variation on a project level by technology, location, scale, duration and participation. The results are discussed in detail on technology level for wind power, energy efficiency, hydro power as well as biomass projects and are compared with regard to CDM and VCS. Our main results indicate that large scale projects often compensate for their under-performance due to economies of time. Furthermore, the duration of projects, their location and structure of participants have significant influence on the success of the projects. The sign of the coefficients of explanatory variables are broadly in line with intuition and related literature, although, due to data availability, they are not always highly significant statistically. Full article
Special Issue in ClimateClimate Variability and Change in the 21th Century Guest Editors: Stefanos Stefanidis, Konstantia Tolika
Deadline: 30 September 2018
Special Issue in ClimateUrban Ventilation and Climate Change Guest Editor: Dong Chen
Deadline: 31 October 2018
Special Issue in ClimateClimate and Climate Niche Models Guest Editor: Tongli Wang
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Special Issue in ClimateClimate Services for Local Disaster Risk Reduction in Africa Guest Editors: Alessandro Pezzoli, Maurizio Tiepolo, Vieri Tarchiani
Deadline: 31 December 2018