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Microinsurance: The Next Revolution?

Jonathan Morduch

in Understanding Poverty

This essay focuses on the design of insurance products for poor customers. Several promising innovations are described: credit life insurance, health insurance partnerships, and weather insurance. ... More

This essay focuses on the design of insurance products for poor customers. Several promising innovations are described: credit life insurance, health insurance partnerships, and weather insurance. Each was created to serve populations that were previously unserved, and workable institutional solutions are emerging. The next step must be to shift from the question of what creates workable institutions to the question of how to refine designs to best serve low-income populations. In doing so, current approaches must be reassessed in order to most improve clients’ lives and to avoid doing unintended harm.Less

Ecology and Environment

R.S. Sharma

in India’s Ancient Past

In ancient times, humans lived on wild produce and hunting birds and animals. However, in the industrial age, the relation of humans with plants and animals has undergone a fundamental change, and ... More

In ancient times, humans lived on wild produce and hunting birds and animals. However, in the industrial age, the relation of humans with plants and animals has undergone a fundamental change, and now many living organisms are preserved through human efforts. The environment has a direct bearing on human efforts. One cannot think of human advance in ancient times without the exploitation of natural resources. The location and size of settlements were conditioned by environmental factors, with soil and climatic conditions which determine the selection of sites. Although rivers were preferred sites for settlement, people settled near lakes and tanks. Rainfall helped human society in pursuing agriculture and founding settlements, but heavy rains during the tropical monsoon deterred people from regular work. A background of ecology and environment may help the study of ancient India, and may be especially useful in the study of the prehistory.Less

Stochastic soil moisture dynamics and vegetation response

Amilcare Porporato and Ignacio Rodríguez-Iturbe

in Celebrating Statistics: Papers in honour of Sir David Cox on his 80th birthday

This chapter describes work on a stochastic soil moisture model that has been used to investigate the relationship between the hydrologic and vegetation dynamics ecohydrology in water-controlled ... More

This chapter describes work on a stochastic soil moisture model that has been used to investigate the relationship between the hydrologic and vegetation dynamics ecohydrology in water-controlled ecosystems. Such systems are complex evolving structures whose characteristics and dynamic properties depend on many links between climate, soil, and vegetation. After a discussion of the soil water balance and a brief account of rainfall modeling, infiltration, and runoff, evapotranspiration and drainage are sketched. The probabilistic modeling of the soil moisture process and of long-term water balance are discussed, followed by minimalist modeling of soil moisture dynamics. The chapter concludes with a brief account of plant water stress, with an application to the Kalahari precipitation gradient.Less

Twenty-first century atmospheric change and deforestation: potential impacts on tropical forests

Wolfgang Cramer, Alberte Bondeau, Sibyll Schaphoff, Wolfgang Lucht, Ben Smith, and Stephen Sitch

in Tropical Forests and Global Atmospheric Change

This chapter quantifies the relative roles of carbon dioxide (CO2), temperature, rainfall, and deforestation on the future extent and condition of tropical rainforests, and examines the magnitude of ... More

This chapter quantifies the relative roles of carbon dioxide (CO2), temperature, rainfall, and deforestation on the future extent and condition of tropical rainforests, and examines the magnitude of their feedbacks on atmospheric CO2 concentrations. A dynamic global vegetation model is applied using multiple scenarios of tropical deforestation (extrapolated from two estimates of current rates) and multiple scenarios of changing climate (derived from four independent off-line general circulation model simulations). Results show that deforestation is likely to produce large losses of carbon, despite the uncertainty concerning exact deforestation rates. Estimates of additional carbon emissions during the 21st century, for all climate and deforestation scenarios, range from 101 to 367 Gt C, resulting in CO2 concentration increases above background values by between 29 and 129 ppm. Notwithstanding this range of uncertainty, continued tropical deforestation will most certainly play a very large role in the build-up of future greenhouse gas concentrations.Less

Irrigation

A. S. Morrison

in Russian Rule in Samarkand 1868-1910: A Comparison with British India

This chapter covers the technical but essential subject of artificial irrigation and the control of water. In a land where rainfall is scarce, controlling canals and water distribution is one of the ... More

This chapter covers the technical but essential subject of artificial irrigation and the control of water. In a land where rainfall is scarce, controlling canals and water distribution is one of the keys to State power, and by and large the Russians were ineffective at doing so. On the face of it, with their vast expansion of irrigation in Punjab, the British were much more successful, but they too had difficulty controlling pre-existing networks.Less

Savannahs

Bryan Shorrocks

in The Biology of African Savannahs

This chapter introduces savannahs and looks at their distribution worldwide. It examines the general climatic and physical conditions that produce them. It briefly looks at the Llanos of the Orinoco ... More

This chapter introduces savannahs and looks at their distribution worldwide. It examines the general climatic and physical conditions that produce them. It briefly looks at the Llanos of the Orinoco basin of Venezuela and Columbia, and the cerrado of Brazil. It also looks briefly at the savannahs of northern Australia where eucalyptus and kangaroos replace the acacias, and ungulates of Africa. The chapter concludes with a geographical survey of the major savannahs of sub-Saharan Africa, from the arid savannahs that border the desert regions in the north and south, through the dry savannah and woodland savannahs that run from northern Kenya to northern Botswana, to the forest savannahs that surround the central lowland rainforest of the Congo basin. The influence of temperature and rainfall on the savannahs of Africa are briefly considered, and the action of the Inter Tropical Convergence Zone described.Less

The vegetation

Bryan Shorrocks

in The Biology of African Savannahs

The various forms of African savannah vegetation are an expression of the interactions of climate, soils, herbivores, fire, and human activities. This chapter examines each of these causes. A brief ... More

The various forms of African savannah vegetation are an expression of the interactions of climate, soils, herbivores, fire, and human activities. This chapter examines each of these causes. A brief description of the common grasses and trees is given, along with a consideration of aspects of their phenology. One geographical area is examined in more detail — the Serengeti grassland/woodland savannah of northern Tanzania. The effects of soil and particularly rainfall upon green biomass, and grass and tree species composition are examined.Less

Climate and Topography

Grady L. Webster and Robert M. Rhode

in Plant Diversity of an Andean Cloud Forest: Inventory of the Vascular Flora of Maquipucuna, Ecuador

This chapter discusses the climate and topography of the Maquipucuna region. The climate of the region is equatorial and wet, with an annual rainfall of 3,230mm at an elevation of 1,630m. Because of ... More

This chapter discusses the climate and topography of the Maquipucuna region. The climate of the region is equatorial and wet, with an annual rainfall of 3,230mm at an elevation of 1,630m. Because of the considerable elevational range in the reserve, the mean annual temperature varies from about 18° C near 1,200m to c. 10°C near the top of Cerro Montecristi. The topography of the Cerro Sosa, which occupies most of the reserve, is steep and dissected, although the main ridge slopes more gradually from the northwestern end at c. 1,700m elevation to the southeastern end in the vicinity of Cerro Montecristi (nearly 2,800 m).Less

Climate Change and Oceanography

Tim R. McClanahan and Joshua E. Cinner

in Adapting to a Changing Environment: Confronting the Consequences of Climate Change

This chapter briefly describes the current understanding of the recent geological history of climate and oceanography in the Indian Ocean and its implications for human-induced climate change. A ... More

This chapter briefly describes the current understanding of the recent geological history of climate and oceanography in the Indian Ocean and its implications for human-induced climate change. A series of dry and wet rainfall oscillations over the past few millenniums are associated with periods of prosperity and hardship for the people of the region. There is an emerging warming trajectory in the region reflected in a number of proxies and confirmed by various sources of environmental data. This is leading to more drought conditions in most of the region, extreme weather, and stressful temperature conditions for marine and other organisms. This trend and heterogeneity is expected to increase and the net effects will challenge the region’s ecology and human wellbeing.Less

Teleology and Elements

Monte Ransome Johnson

in Aristotle on Teleology

Did Aristotle consider the properties of the elements to be teleologically explicable? According to some commentators, he did not, but considered these to operate according to material, moving, or ... More

Did Aristotle consider the properties of the elements to be teleologically explicable? According to some commentators, he did not, but considered these to operate according to material, moving, or mechanical causes. According to others, he did, and this is evidence of his commitment to an “overall” or “global” teleology. Both of the positions are wrong. Aristotle did consider each of the elements teleologically explicable, but he considered the beneficiaries of their properties and motions to be the elements themselves. This is relatively clear in the case of ether, the element that composes the heavenly bodies: it has a simple motion in a circle, which is a manifestation of the intelligence of the extra-terrestrial bodies. But the other elements are included in a cycle of transmutation that guarantees their perpetual existence. This is a benefit to them according to the axiom: it is better to exist than not exist. Thus, rainfall is a necessary and cyclical process (happening completely independently of the needs of living things), but it is also somehow benefits the elements that are transformed in the process, for in so doing they complete cycles that resemble or imitate the eternal cycles of the heavenly bodies.Less

Burning the Bush: The Development of Australia’s Southwest Botanical Province

Fiona Kost

in Humans and the Environment: New Archaeological Perspectives for the Twenty-First Century

Though early historical records frequently mention Aboriginal, or Noongar, firing in south-western Australia, little is known about how the Noongar people ... More

Though early historical records frequently mention Aboriginal, or Noongar, firing in south-western Australia, little is known about how the Noongar people managed the vegetation with fire, or the impact this has had on the environment. This study uses interdisciplinary archaeology, with information from ethnographic data, historical records, and pollen records from the last 6,000 years to determine the actions of the Noongar people and demonstrate how the Southwest Botanical Province can be viewed as an artefact of Noongar land management. It is widely accepted that Aboriginal people have had an effect on some of Australia’s vegetation types through fire (Bowman 1998; Hallam 1975; Kershaw et al. 2002) although the extent of the influence of Aboriginal firing is debated (Mooney et al. 2007). However, pollen data and the study of fire indicators in Xanthorrhoea and Eucalyptus trunks have been used to demonstrate that the frequency of fire events in the south-west has decreased since European colonization (Atahan et al. 2004; Ward et al. 2001), resulting in the loss of fire-dependent vegetation species and changes in vegetation distribution patterns. This disruption of the vegetation communities has been compounded by the extensive clearing of land for farming and the displacement of the Noongar people (Dodson 2001). The impact that European colonization had on vegetation becomes more apparent as an understanding of the Noongar fire management practices is gained. There is increasing acknowledgement by researchers of the need to understand the influence of the past fire regime on vegetation patterns and to acknowledge traditional land management practices (Hopper and Gioia 2004), as well as the changes caused by European attempts to create a ‘natural’ regime, so that land management groups can take them into account when determining modern-day prescribed burning timetables. Archaeological studies such as this one can provide a unique insight into the past actions of people such as the Noongar, allowing us to determine how they shaped the landscape prior to European colonization (see Balée, Chapter 3 this volume for a more direct discussion of the ‘indigenous’ nature of pre-colonial landscapes; see Stump, Chapter 10 this volume for similar discussions of colonial and postcolonial environmental narratives). Less

Impact of Water Harvesting and Recharge in Naturally Water-Scarce Regions *

M. Dinesh Kumar

in Managing Water in River Basins: Hydrology, Economics, and Institutions

This chapter evaluates the potentials of, and pitfalls in, rainwater harvesting and groundwater recharging in water-scarce regions of India. It analyses macro and micro level hydrological and ... More

This chapter evaluates the potentials of, and pitfalls in, rainwater harvesting and groundwater recharging in water-scarce regions of India. It analyses macro and micro level hydrological and geo-hydrological data including rainfall magnitudes and variability, and runoff. The findings suggest that rainwater harvesting and groundwater recharging projects have an extremely limited potential in water-scarce regions of India from the point of view of basin level hydrological impacts and economic viability. This chapter describes the case study of the Narmada River Basin to illustrate the relative importance of blue and green water in managing basin water economies.Less

Changing Surface Water–Groundwater Interactions in Narmada River Basin

M. Dinesh Kumar

in Managing Water in River Basins: Hydrology, Economics, and Institutions

This chapter examines the changes in the interaction between surface water and groundwater in Narmada River Basin. It analyses the historical flows, long-term trends in rainfall in the basin, and ... More

This chapter examines the changes in the interaction between surface water and groundwater in Narmada River Basin. It analyses the historical flows, long-term trends in rainfall in the basin, and changes in rainfall–runoff relationships between different time periods. It investigates whether change in groundwater draft had caused changes in groundwater–surface water interactions, particularly when groundwater outflows into the surface streams contributing to river flows.Less

Spatial Scale and Species Diversity: Building Species–Area Curves from Species Incidence

Jack J. Lennon and William Edward Kunin

in Biodiversity in Drylands: Toward a Unified Framework

This chapter is largely focused on the species–area relationship (SAR), although it may not seem so for much of the time. Bear with us; we will get there ... More

This chapter is largely focused on the species–area relationship (SAR), although it may not seem so for much of the time. Bear with us; we will get there in the end. Our aim is to provide insights into how the relationship works, and how it is built. This leads us to take a rather reductionist approach, and to break down the SAR into its component parts. We will spend a substantial section of this chapter examining these pieces and their properties. We will then explore the logic by which the parts are reassembled, and will explore how biological and biogeographical properties of a system may affect the SAR. Before attempting this feat, however, we should begin with a brief discussion of the SAR itself, to explain why it is worth making such a fuss over. The SAR is, after all, only a simple graph: a plot of the number of species found in a sample as a function of the area sampled. Ecologists being an argumentative lot, we cannot even all agree on what this plot should look like; Gleason (1922, see also Williams 1964) argued that the absolute number of species should be plotted as a function of the logarithm of area, whereas Arrhenius (1921, see also Preston 1960) suggested that both species and area should be plotted logarithmically. Connor and McCoy (1979) found cases that fit both models, and two others besides (log species by untransformed area, and neither variable transformed). However it’s plotted, the SAR is not even a particularly attractive or elegant graph—at its best (!) it is simply a straight diagonal line within a tight scatter of datapoints on a rectangular plot. Hardly something to set the pulse racing. Yet the SAR is exciting stuff; that simple line encapsulates a great deal of information about the diversity of biological systems across a wide range of scales. Less

Smoothing—median values

Steve Selvin

in The Joy of Statistics: A Treasury of Elementary Statistical Tools and their Applications

As the term smoothing suggests, data are made more similar to represent a clearer and more accessible picture of the relationships within the collected data.

The Zen of the Beach: Musings on a River Of Sand

Wolf H. Berger

in Ocean: Reflections on a Century of Exploration

This chapter focuses on the processes shaping coastal landscapes and the factors that contribute to the formation of beaches. It begins by discussing waves, where they come from, how they change ... More

This chapter focuses on the processes shaping coastal landscapes and the factors that contribute to the formation of beaches. It begins by discussing waves, where they come from, how they change through the seasons, and how they move sand or beach materials. The chapter then talks about the nature of cliffs and the process of cliff erosion. It also describes the geological and climatic factors for beach formation, such as river flows, rainfall, and floods.Less

Shading and Cooling in City Climates

William G. Wilson

in Constructed Climates: A Primer on Urban Environments

The heating of impervious surfaces generally matches and confirms the scale of urban heat island warming, and also matches the amount of heat that evaporates a light rain. The chapter examines the ... More

The heating of impervious surfaces generally matches and confirms the scale of urban heat island warming, and also matches the amount of heat that evaporates a light rain. The chapter examines the role urban vegetation plays in cooling cities and treating storm water, and discusses whether any significant energy reduction and carbon sequestration benefits can be expected. Comparing the cooling potential of a tree shows that a tree just can't transpire enough water to cool these high thermal mass surfaces. Further, trees experiencing realistic urban scenarios have an even bigger challenge as their transpiration systems shut down due to high heat. Simply painting the cement and asphalt surfaces white, on the other hand, could greatly change how much heat they absorb. Surprisingly, lawns have a higher potential than trees for cooling via transpiration, and interesting approaches combine parking lots with grass.Less