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Climate change is expected to alter the major components of hydrological regime such as streamflow and water availability. The magnitude and their impacts are still uncertain. Therefore, it is highly required to study streamflow and flood vulnerability in tropical river basins particularly urbanised basin such as Langat River Basin. This study aims to model the future streamflow of Langat River Basin due to climate change using Rainfall-Runoff Inundation (RRI) model. Daily rainfall data obtained from Department of Irrigation and Drainage Malaysia and topographic data from HydroSHEDS at 15-second resolution were used. The projected future rainfall (2075–2099) is extracted from MRI-AGCM3.2s under the worst carbon emission scenario, RCP8.5. The annual maximum series of 1-day rainfall is selected for statistical bias correction using Quantile Mapping. The General Circulation Model data were found to be greatly corrected with reasonable Nash–Sutcliffe efficiency, Percent bias and Root Mean Square Error values. The mean of maximum 1-day future rainfall in Langat River Basin is found to be inconsistent where parts of the upstream will experience an increment at about 7% while other parts decrease at 8%. Meanwhile, the rainfall at downstream area are expected to decrease at 40%. Based on RRI simulation, the future streamflow can achieve up to 92% increment.

Taiwan is located between the world's largest landmass, the continent of Asia, and its largest ocean, the Pacific Ocean. The Tropic of Cancer passes through the island of Taiwan, giving it a subtropical and tropical oceanic climate. High temperatures and rainfall and strong winds characterize the climate. Because of Taiwan's position in the Asian monsoon region, its climate is greatly influenced by monsoons as well as by its own complicated topography. The annual mean temperatures in the lowlands are 22–25°C, and the monthly mean temperature exceeds 20°C for eight months starting with April each year. The period from June to August is the hottest season with mean temperatures of 27–29°C. Temperatures are cooler between November and March; in most places, the coldest monthly mean temperature is above 15°C. The climate is mild rather than cold and temperatures only fall dramatically when a cold front affects the region. Average annual rainfall in the lowlands of Taiwan is in the range of 1,600–2,500mm. Due to the influences of topography and the monsoon climate, the rainfall differs greatly with different areas and seasons. In mountainous areas, average rainfall may exceed 4,000mm/yr. Rainfall is generally higher in mountainous areas than in lowland areas, higher in the east than in the west, and higher on windward slopes than on the leeward side. The northeast monsoon prevails during the winter; this is the rainy season in the north though rainfall is not intense. But the same winter period is the dry season in the south. During the summer, the southwest monsoon prevails, often giving rise to convective thunderstorms and bringing intense and copious rainfall. With added downpours brought by typhoons, this season often accounts for over 50% of annual rainfall in the south so that central and southern regions often suffer greatly. Relative humidity on the island of Taiwan, surrounded by ocean, is high, usually measuring in the range of 78–85%. In the north, relative humidity is higher during winter than during summer. The situation in the south is the opposite. Over the past 100 years, the rainfall in the north has increased, while the rainfall in the south has decreased. The trend is not as consistent as that of the temperature change (Environmental Protection Administration, Executive Yuan, R.O.C. (Taiwan), 2002).

This paper examines localized conditions and responses to what people see as ordinary variations in the weather, drawing on their own archive of knowledge and practice for “coping” with it, as distinct from year-to-year climate patterns that may entail “adaptation.”

This paper draws on ethnographic field research and rainfall statistics collected in 1968–1969 and 1987–1988, in a rural area of Western Nigeria where guinea-savannah small-scale farmers now grow increasingly for the market. Research in the 1980s was designed to track all changes since the 1960s. It is revisited here to draw out the rainfall variable.

In the 1980s, farmers noted a decline in the first rains of the early growing season, and a change in the short dry season, over a period of three years, in a way that differed from the expected patterns of twenty years previously. The shift is confirmed by rainfall statistics. Their crop repertoire choices are noted.

The paper’s themes are culled from a broader range of observations over the 20 years. The interweaving of the variables in complex change over several decades is noted as a research challenge.

Local time series, interpreted through the local archive of social and technical practice, offers a rich entry point into what the recent AAA climate change review refers to as coping and adaptation, with respect to what I call “weather” and “climate.”

This chapter presents a case study on smallholder vulnerability and adaptation to long-term desiccation in the West African Sahel. Climatologists recognize Sahelian desiccation as a long-term multi-decadal dry period that persisted from roughly 1968 to 1995. This study draws on fine-scale ethnographic and daily rainfall data to elucidate local perspectives on this broad regional process. As such, this provides a window on the local lived experience of regional climate variability.

This study draws on multiple periods of ethnographic fieldwork in two different Mossi areas in north-central Burkina Faso (West Africa). Fieldwork consisted of key informant interviews, household surveys, and participant observation. The authors incorporate daily precipitation data from two meteorological stations provided by the General Directorate of Meteorology of Burkina Faso. Researchers assembled this data and graphed daily rainfall totals for individual rainfall seasons in the years preceding each period of fieldwork. The qualitative and quantitative data are analyzed by using a Sustainable Livelihoods (SL) framework.

The study finds that local perceptions of increased rainfall variability correspond to patterns evident in daily rainfall records for individual stations. Additionally, the authors document how rural producers are negatively affected by both intra-seasonal and multi-decadal rainfall variability. Mossi smallholders have adapted through new cropping patterns, livelihood diversification, and investments in agricultural intensification. These adaptations have been largely successful and could be adopted by other Sahelian groups in their efforts to adapt to climate change.

Fieldwork took place over several years in two different departments and five localities. The two anthropologists used a common livelihoods analytical framework but different research protocols over this time span. Thus, the data collection was not systematic across all locations and time periods. This limits the degree to which results are representative beyond surveyed localities at their respective points in time.

This study presents local views and perceptions of regional climate variability and ecological change. It is a rare bottom-up perspective supplemented with precipitation data.

This paper attempts to understand how the interaction of natural disasters and human behaviour during wartime led to famines in three regions under imperial control around the Indian Ocean. The socio-economic structure of these regions had been increasingly differentiated over the period of imperial rule, with large proportions of their populations relying on agricultural labour for their subsistence.

Before the war, food crises in each of the regions had been met by the private importation of grain from national or overseas surplus regions: the grain had been made available through a range of systems, the most complex of which was the Bengal Famine Code in which the able-bodied had to work before receiving money to buy food in the market.

During the Second World War, the loss of control of normal sources of imported grain, the destruction of shipping in the Indian Ocean (by both sides) and the military demands on internal transport systems prevented the use of traditional famine responses when natural events affected grain supply in each of the regions. These circumstances drew the governments into attempts to control their own grain markets.

The food crises raised complex ethical and practical issues for the governments charged with their solution. The most significant of these was that the British Government could have attempted to ship wheat to Bengal but, having lost naval control of the Indian Ocean in 1942 and needing warships in the Atlantic and Mediterranean in 1943 chose to ignore the needs of the people of Bengal, focussing instead on winning the war.

In each of the regions governments allowed/encouraged the balkanisation of the grain supply – at times down to the sub-district level – which at times served to produce waste and corruption, and opened the way for black markets as various groups (inside and outside government ranks) manipulated the local supply.

People were affected in different ways by the changes brought about by the war: some benefitted if their role was important to the war-effort; others suffered. The effect of this was multiplied by the way each government ‘solved’ its financial problems by – in essence – printing money.

Because of the natural events of the period, there would have been food crises in these regions without World War II, but decisions made in the light of wartime exigencies and opportunities turned crises into famines, causing the loss of millions of lives.

Chronicles and literary records show that Sri Lanka has been affected by various natural disasters from time to time in the past, as it is now. The sea surge/coastal flooding during King Kelani Tissa's reign, around 190 BC could have been a tsunami. A severe drought and famine known as Beminitiya Seya occurred during the intermittent reign of the Brahmin King Thiya (Tissa) and King Valagamba (89–77 BC). There are also references to droughts prior to this, namely, Akkakayika Seya (it is said that about 24,000 monks died and others left the country, and some of those who remained survived by eating kara leaves). Subsequently, this led King Valagamba to undertake to record the sayings of the Buddha (Tripitaka) for posterity. Duttagamini (161–137 BC), Ekanalika Seya during the reign of King Kunchanaga (187–189 AD) and others, none of which had been as severe as Beminitiya Seya. Apart from these extreme hazard events other incidents have been reported, including the flooding incidents during the British rule (National Disaster Management Plan, 2007).

The Monsoon Asian region has a much wider rainfall distribution than other regions of the world. The countries in this region are characterized mostly by floods and typhoons, which result from the interplay among the ocean, the atmosphere, and the land. Thus, many factors affect the strength of the rainfall, including sea surface temperatures in the Indian and Pacific Oceans, variations in solar output, land snow cover and soil moisture over the Asian continent, and the position and strength of prevailing winds. The links between these factors and monsoons appear to wax and wane over time, and the observational record is too short to explain this longer-term variability. Precipitation and surface wind maps of Asia during the summer months of June to August show the average spatial patterns of monsoon circulation and moisture.

Japan is an island arc that sits in the monsoon region, and is under the influence of warm and moist air masses in summer and cool air masses in winter. The moisture that is taken in the lower leaves of the air masses over the sea is poured on the country by typhoons in summer, by snowfall in winter, by the “Bai-u Front” (in Japanese) in June and July, and by depressions and fronts in all seasons. Owing to Japan's slender shape and complicated landform, aerial differences in climate are great. Japan is located on the eastern edge of the monsoonal region of Asia, and its climate varies according to seasonal and regional conditions. Typically, heavy rains occur in various parts of the country, both during the rainy season in June and July and during the typhoon season from August to October. This precipitation is predominantly in the form of locally specific temporary downpours. In winter, the northern part of the country usually receives heavy snowfall that causes prolonged floods in spring from the melting of snow. The average amount of precipitation is 1,800mm (70 inches) a year. This is two or three times the amount received in other areas of the same latitude. In the southern Pacific coast areas, rainfall amounts to 4,000mm (160 inches). Precipitation in Tokyo is twice as much as other large cities in western countries. Some 50–60% of the annual precipitation in the Pacific coast of Japan is concentrated from June to October. Artificial changes in natural environments are rapid and large, accompanying the great increase in economic activity and exploitation (Nakano, Kadomura, Mizutani, Okuda, & Sekiguchi, 1974). Although the country's 10% of land area is flood prone, about 50% of the population lives in floodplains and almost 75% of the property is concentrated in the floodplains (JWF, 2006).

Case studies from many countries indicate that even when rainfall is high drought can still occur. Droughts have been recorded in Bangladesh, where the rainfall is 2,300mm per year, and in Luang Prabang, Laos, where the annual rainfall is 3,200mm. Similarly, the highest Standardized Precipitation Index (SPI) value of 2.78 indicates a possibility of floods in Cambodia. Identification of a threshold SPI value is necessary to pinpoint impending drought. Since SPI values reflect only the rainfall situation and not the existing water availability in reservoirs and canal systems, such a detailed impact-assessment study should also compare the duration of a negative SPI value with that of reduction in the available water from various sources, including groundwater, reservoirs, and canal irrigation systems. So drought occurs not only because of lack of rainfall but also because of bad practices of water usage and water management.

The US Department of Agriculture (USDA), Soil Conservation Services (SCS) rainfall-runoff model has been applied worldwide since 1954 and adopted by Malaysian government agencies. Malaysia does not have regional specific curve numbers (CN) available for the use in rainfall-runoff modelling, and therefore a SCS-CN practitioner has no option but to adopt its guideline and handbook values which are specific to the US region. The selection of CN to represent a watershed becomes subjective and even inconsistent to represent similar land cover area. In recent decades, hydrologists argue about the accuracy of the predicted runoff results from the model and challenge the validity of the key parameter, initial abstraction ratio coefficient (λ) and the use of CN. Unlike the conventional SCS-CN technique, the proposed calibration methodology in this chapter discarded the use of CN as input to the SCS model and derived statistically significant CN value of a specific region through rainfall-runoff events directly under the guide of inferential statistics. Between July and October of 2004, the derived λ was 0.015, while λ = 0.20 was rejected at alpha = 0.01 level at Melana watershed in Johor, Malaysia. Optimum CN of 88.9 was derived from the 99% confidence interval range from 87.4 to 96.6 at Melana watershed. Residual sum of square (RSS) was reduced by 79% while the runoff model of Nash–Sutcliffe was improved by 233%. The SCS rainfall-runoff model can be calibrated quickly to address urban runoff prediction challenge under rapid land use and land cover changes.