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Article

Álvaro José Back and Luana Pasini Miguel

The purpose of this paper is to evaluate the seasonal and spatial variations in the statistical descriptors of the Markov chain model as well as the expected values of the…

Abstract

Purpose

The purpose of this paper is to evaluate the seasonal and spatial variations in the statistical descriptors of the Markov chain model as well as the expected values of the length of dry and wet days and to estimate the probability of dry and rainy sequences in the state of Santa Catarina.

Design/methodology/approach

Daily rainfall data from 1970 to 2013 of five rainfall stations in the state of Santa Catarina were used. To model the sequence of dry and wet days, the first order of the Markov chain was used. The statistical descriptors of the Markov model were evaluated, as well as the expected values of the length of dry and wet days and the number of dry and rainy days for each month. Along with geometric distribution, the probability of occurrence of sequences of dry and rainy days was determined. The adherence of the data to geometric distribution was evaluated using the Kolmogorov-Smirnov test.

Findings

The results showed that there is a seasonal and spatial variation in Markov model descriptors and also in the duration of the dry and rainy periods. These variations may be related to the mechanisms responsible for the formation and distribution of rainfall in the state, such as the air masses and relief. The Lages station, located in the Plateau of Santa Catarina, had the highest P00 values, reflecting more stable conditions of the atmosphere. In autumn and winter, no marked differences were found between the coastal stations and west of the state. The geometric distribution was adequate for estimating the probability of dry and rainy days.

Originality/value

Although some work has already been carried out on the modeling of the Markov chain in the state of Santa Catarina, this study was found to be more complete with the use of various statistical descriptors of the model and its application in estimating the duration of the cycles of dry and wet periods and the number of rainy days in the period.

Details

Management of Environmental Quality: An International Journal, vol. 28 no. 1
Type: Research Article
ISSN: 1477-7835

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Article

Mazen J. Al-Kheetan, Mujib M. Rahman and Denis A. Chamberlain

The purpose of this paper is to investigate the performance of new and innovative crystallising materials, so-called moisture blockers, in protecting masonry structures…

Abstract

Purpose

The purpose of this paper is to investigate the performance of new and innovative crystallising materials, so-called moisture blockers, in protecting masonry structures from water ingress.

Design/methodology/approach

Two masonry wells were constructed: one with lime mortar and the other with cement-based mortar in order to hold water inside, and then a moisture blocking product was applied at dry and wet conditions to the negative hydrostatic pressure side. The moisture levels of both, the surfaces and the substrate, were then observed for 14 days.

Findings

Results demonstrated that moisture blocking materials are effective methods in reducing the levels of surface moisture for bricks, mortar-brick interface and mortar.

Originality/value

Moisture blockers use the available water in the masonry to block the passage of water to the surface of the masonry, filling pores, cracks and spaces at the interface between mortar and bricks. This approach will deliver a wider understanding of how water-based moisture blockers work and the scenarios in which they are best applied. The pursuit of possible environmentally friendly and sustainable materials for use in the construction industry is the key driver of this research.

Details

International Journal of Building Pathology and Adaptation, vol. 36 no. 1
Type: Research Article
ISSN: 2398-4708

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Article

BaoZhuang Sun, Wenju Liao, Zhong Li, Zhiyong Liu and Cuiwei Du

To study the corrosion behavior of pipeline steel in coastal areas, a tidal seawater macro-cell corrosion device was built using a cycle soaking tank and a macro-cell…

Abstract

Purpose

To study the corrosion behavior of pipeline steel in coastal areas, a tidal seawater macro-cell corrosion device was built using a cycle soaking tank and a macro-cell corrosion facility to simulate the corrosion behavior of pipeline steel in a simulated coastal environment (dry and wet alternations during seawater-soil corrosion macro-cell processes).

Design/methodology/approach

The corrosion behaviors were studied via the weight loss method, electrochemical methods and morphological observations on corrosion.

Findings

The results show that during the initial stage of tidal seawater/soil macro-cell corrosion process of the X65 steel, the working electrode on the seawater side is the anode of the macro-battery. As corrosion progresses, the anode and the cathode of the macro-battery become inverted. As the area ratio and the dry – wet ratio increase, the time of anode and cathode inversion shortens. Galvanic current density decreases as the dry – wet ratio increases and increases as the area ratio increases. The corrosion process of macro-cell is affected by the reversal of anode and cathode. After the reversal of anode and cathode, the corrosion rate is mainly controlled by dry – wet alternating corrosion.

Originality/value

The corrosion behavior of a pipeline steel in a coastal environment was studied using a tidal seawater macro-cell corrosion device. The synergism effect between the tidal seawater and seawater-soil macro-cell on corrosion behavior was clarified.

Details

Anti-Corrosion Methods and Materials, vol. 66 no. 3
Type: Research Article
ISSN: 0003-5599

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Article

Justin Sexton, Yvette Everingham and Bertrand Timbal

This study aims to investigate the effects of climate change on harvestability for sugarcane-growing regions situated between mountain ranges and the narrow east…

Abstract

Purpose

This study aims to investigate the effects of climate change on harvestability for sugarcane-growing regions situated between mountain ranges and the narrow east Australian coastline.

Design/methodology/approach

Daily rainfall simulations from 11 general circulation models (GCMs) were downscaled for seven Australian sugarcane regions (1961:2000). Unharvestable days were calculated from these 11 GCMs and compared to interpolated observed data. The historical downscaled GCM simulations were then compared to simulations under low (B1) and high (A2) emissions scenarios for the period of 2046-2065. The 25th, 50th and 75th percentiles of paired model differences were assessed using 95 per cent bootstrapped confidence intervals.

Findings

A decrease in the number of unharvestable days for the Burdekin (winter/spring) and Bundaberg (winter) regions and an increase for the Herbert region (spring) were plausible under the A2 scenario. Spatial plots identified variability within regions. Northern and southern regions were more variable than central regions.

Practical implications

Changes to the frequency of unharvestable days may require a range of management adaptations such as modifying the harvest period and upgrading harvesting technologies.

Originality/value

The application of a targeted industry rainfall parameter (unharvestable days) obtained from downscaled climate models provided a novel approach to investigate the impacts of climate change. This research forms a baseline for industry discussion and adaptation planning towards an environmentally and economically sustainable future. The methodology outlined can easily be extended to other primary industries impacted by wet weather.

Details

International Journal of Climate Change Strategies and Management, vol. 7 no. 1
Type: Research Article
ISSN: 1756-8692

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Article

S. Matthews, K. Nguyen and J.L. McGregor

Fuel moisture is an important determinant of fire behaviour. Changes in climate will result in changes in fuel moisture and this will impact fire management by modifying…

Abstract

Purpose

Fuel moisture is an important determinant of fire behaviour. Changes in climate will result in changes in fuel moisture and this will impact fire management by modifying the length and severity of the fire season and by changing opportunities for prescribed burning. This paper aims to examine the effect of climate on fuel moisture in Eucalypt forests.

Design/methodology/approach

A climate model is used to predict weather for five Australian cities from 1961 to 2100 under a high‐emissions scenario. Time series are extracted from the model and used as boundary conditions for a process‐based fuel moisture model. Fuel moisture predictions are used to examine two management variables: the number of days suitable for prescribed burning in spring, and the number of days when fire could burn in summer.

Findings

There were significantly more fire days in warmer‐drier years. The number of days with extremely low fuel moisture was also higher in warmer‐drier years. Variation in the number of burning days was narrower than for fire days but the number of burning days was lower in warmer‐drier years. The lower number of burning days in warm years was due to a higher rate of fuel drying in these years.

Research limitations/implications

Analysis was limited to Australian locations. In future, the work should be expanded to include Eucalypt plantations on other continents.

Practical implications

The changes predicted will require changes to fire management practices, particularly the timing of prescribed burning.

Originality/value

This paper uses a new, physically based method to examine the effect of climate change on fuel moisture. It will be useful to fire managers seeking to adapt to a changing climate.

Details

International Journal of Climate Change Strategies and Management, vol. 3 no. 1
Type: Research Article
ISSN: 1756-8692

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Article

Sergio Cabrales, Jesus Solano, Carlos Valencia and Rafael Bautista

In the equatorial Pacific, rainfall is affected by global climate phenomena, such as El Niño Southern Oscillation (ENSO). However, current publicly available methodologies…

Abstract

Purpose

In the equatorial Pacific, rainfall is affected by global climate phenomena, such as El Niño Southern Oscillation (ENSO). However, current publicly available methodologies for valuing weather derivatives do not account for the influence of ENSO. The purpose of this paper is to develop a complete framework suitable for valuing rainfall derivatives in the equatorial Pacific.

Design/methodology/approach

In this paper, we implement a Markov chain for the occurrence of rain and a gamma model for the conditional quantities using vector generalized linear models (VGLM). The ENSO forecast probabilities reported by the International Research Institute for Climate and Society (IRI) are included as independent variables using different alternatives. We then employ the Esscher transform to price rainfall derivatives.

Findings

The methodology is applied and calibrated using the historical rainfall data collected at the El Dorado airport weather station in Bogotá. All the estimated coefficients turn out to be significant. The results prove more accurate than those of Markovian gamma models based on purely statistical descriptions of the daily rainfall probabilities.

Originality/value

This procedure introduces the novelty of incorporating variables related to the climatic phenomena, which are the forecast probabilities regularly published for the occurrence of El Niño and La Niña.

Details

Agricultural Finance Review, vol. 80 no. 4
Type: Research Article
ISSN: 0002-1466

Keywords

Content available
Article

Yuanzhuo Zhu, Zhihua Zhang and M. James C. Crabbe

Climatic extreme events are predicted to occur more frequently and intensely and will significantly threat the living of residents in arid and semi-arid regions…

Abstract

Purpose

Climatic extreme events are predicted to occur more frequently and intensely and will significantly threat the living of residents in arid and semi-arid regions. Therefore, this study aims to assess climatic extremes’ response to the emerging climate change mitigation strategy using a marine cloud brightening (MCB) scheme.

Design/methodology/approach

Based on Hadley Centre Global Environmental Model version 2-Earth System model simulations of a MCB scheme, this study used six climatic extreme indices [i.e. the hottest days (TXx), the coolest nights (TNn), the warm spell duration (WSDI), the cold spell duration (CSDI), the consecutive dry days (CDD) and wettest consecutive five days (RX5day)] to analyze spatiotemporal evolution of climate extreme events in the arid Sahara-Sahel-Arabian Peninsula Zone with and without MCB implementation.

Findings

Compared with a Representative Concentration Pathways 4.5 scenario, from 2030 to 2059, implementation of MCB is predicted to decrease the mean annual TXx and TNn indices by 0.4–1.7 and 0.3–2.1°C, respectively, for most of the Sahara-Sahel-Arabian Peninsula zone. It would also shorten the mean annual WSDI index by 118–183 days and the mean annual CSDI index by only 1–3 days, especially in the southern Sahara-Sahel-Arabian Peninsula zone. In terms of extreme precipitation, MCB could also decrease the mean annual CDD index by 5–25 days in the whole Sahara and Sahel belt and increase the mean annual RX5day index by approximately 10 mm in the east part of the Sahel belt during 2030–2059.

Originality/value

The results provide the first insights into the impacts of MCB on extreme climate in the arid Sahara-Sahel-Arabian Peninsula zone.

Details

International Journal of Climate Change Strategies and Management, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1756-8692

Keywords

Content available
Article

Seung Kyu LEE and Truong An Dang

This study aims to investigate aspects related to the changing trends of the rainfall extremes in the entire Mekong Delta in the period of 32 years (1984-2015) applying…

Abstract

Purpose

This study aims to investigate aspects related to the changing trends of the rainfall extremes in the entire Mekong Delta in the period of 32 years (1984-2015) applying rainfall extreme indices. First, the homogeneity tests were applied to assess the quality of observed rainfall data series. The authors, then, investigated three rainfall indices including the number of very heavy rainfall days 20 mm (R20), number of days above 50 mm (R50) and number of days above 100 mm (R100) applying the Mann-Kendall test and Sen’s slope estimate.

Design/methodology/approach

First, the homogeneity tests were applied to assess the quality of observed rainfall data series. The authors, then, investigated three rainfall indices including the number of very heavy rainfall days 20 mm (R20), number of days above 50 mm (R50) and number of days above 100 mm (R100) applying the Mann-Kendall test and Sen’s slope estimate.

Findings

The results of R20 pointed out that an insignificant upward tendency was found in the coastal provinces, whereas an insignificant downward tendency was also recorded in the inland provinces. Regarding the number of R50, a similar trend to R20 was recorded with five stations slightly increased and five stations slightly decreased. For the number of R100, the results recorded an absence of significant trends over the entire study area. Approximately 58.5% of stations show a slightly decreasing trend, while 41.5% of the remaining stations recorded a slightly increasing trend.

Originality/value

For the number of R100, the results recorded an absence of the significant trends over the entire study area. Approximately 58.5% of stations show a slightly decreasing trend, while 41.5% of the remaining stations recorded a slightly increasing trend. Of note is the fact that the number of R100 occurred more frequently in the northern provinces, which means the northern region is facing a high risk of flooding.

Details

International Journal of Climate Change Strategies and Management, vol. 12 no. 5
Type: Research Article
ISSN: 1756-8692

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Article

IT is evident from the numerous press cuttings which are reaching us, that we are once more afflicted with one of those periodical visitations of antagonism to Public…

Abstract

IT is evident from the numerous press cuttings which are reaching us, that we are once more afflicted with one of those periodical visitations of antagonism to Public Libraries, which occasionally assume epidemic form as the result of a succession of library opening ceremonies, or a rush of Carnegie gifts. Let a new library building be opened, or an old one celebrate its jubilee, or let Lord Avebury regale us with his statistics of crime‐diminution and Public Libraries, and immediately we have the same old, never‐ending flood of articles, papers and speeches to prove that Public Libraries are not what their original promoters intended, and that they simply exist for the purpose of circulating American “Penny Bloods.” We have had this same chorus, with variations, at regular intervals during the past twenty years, and it is amazing to find old‐established newspapers, and gentlemen of wide reading and knowledge, treating the theme as a novelty. One of the latest gladiators to enter the arena against Public Libraries, is Mr. J. Churton Collins, who contributes a forcible and able article, on “Free Libraries, their Functions and Opportunities,” to the Nineteenth Century for June, 1903. Were we not assured by its benevolent tone that Mr. Collins seeks only the betterment of Public Libraries, we should be very much disposed to resent some of the conclusions at which he has arrived, by accepting erroneous and misleading information. As a matter of fact, we heartily endorse most of Mr. Collins' ideas, though on very different grounds, and feel delighted to find in him an able exponent of what we have striven for five years to establish, namely, that Public Libraries will never be improved till they are better financed and better staffed.

Details

New Library World, vol. 6 no. 1
Type: Research Article
ISSN: 0307-4803

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Article

Martin Odening and Zhiwei Shen

– The purpose of this paper is to review some challenges of insuring weather risk in agriculture and to discuss potential remedies for these problems.

Abstract

Purpose

The purpose of this paper is to review some challenges of insuring weather risk in agriculture and to discuss potential remedies for these problems.

Design/methodology/approach

The paper is developed as a narrative on weather insurance based largely on existing literature.

Findings

Weather risks show characteristics that often violate classical requirements for insurability. First, some weather risks, particularly slowly emerging weather perils like drought, are spatially correlated and cause systemic risks. Second, climatic change may increase the volatility of weather variables and lead to non-stationary loss distributions, which causes difficulties in actuarial ratemaking. Third, limited availability of yield and weather data hinders the estimation of reliable loss distributions.

Practical implications

Some of the approaches discussed in this review, such as time diversification, local test procedures and the augmentation of observational data by expert knowledge, can be useful for crop insurance companies to improve their risk management and product design.

Originality/value

This study provides background and development information regarding weather insurance and also presents statistical tools and actuarial methods that support the assessment of weather risks as well as the design of weather and yield insurance products.

Details

Agricultural Finance Review, vol. 74 no. 2
Type: Research Article
ISSN: 0002-1466

Keywords

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