Kitui is a semi-arid and sparsely populated rural county, where low and unreliable rains create water insecurities for fragile cropping and livestock systems. Searching for and fetching water continue to dominate the daily lives of women and children, with households using around four different sources in a year. Rains drive a sharp shift in source choice from groundwater-based handpumps and piped schemes to free surface water sources, risking ill health. This, in turn, decrease revenues for water service providers, jeopardising operation and maintenance services in wet seasons. The Water Diaries reveal different expenditure groups, from those that incur no expenses throughout the year to those that pay more than 10 per cent of their annual expenditures for water. Yet daily consumption remains at only 20 litres per person. Donor investments in water security are fragile and fleeting with devolution transferring a legacy of past failures to newly elected county governments. The results of a professional service delivery model have illustrated how the government and donors can guarantee reliable drinking water services at lower costs, though action and uptake are slow. While hydroclimatic conditions are harsh, weak governance and opaque accountability compound challenges and waste investments.

Despite the contrasts in history and hydroclimatic contexts, the water diaries of Bangladeshis and Kenyans reveal similar daily practices. Rains stand out as the most defining driver of water source choice. Rural populations in Khulna and Kitui shift to rainwater when available, whether harvested in containers from their own roof catchments or in rocks and dams. Whether in sarees or sarongs, in kolshis stacked on the waist or jerrycans balanced on the head, women are the primary drawers of water. When water needs to be transported via motorcycles or boats, a well is dug or a community tube well is installed, men come onto the scene. Individual practices are shaped by institutional behaviours and the quality of water governance. Regulation is missing or ineffective for rural drinking water services in Kitui and Khulna, while non-compliance is normalised in case of urban water pollution in Dhaka and unreliable piped supply in Lodwar. Our findings propose that policy and practice focus more attention on the interactions between rainfall and water use behaviours in a changing climate, and the need for better information on water risks for institutional accountability and sustainable finance. We finally chart where change is happening to improve water security in Bangladesh and the opportunities that exist in Kenya.

Instrument calibrations are both one of the most important, and yet sometimes one of the most neglected, areas of weather measurement. This chapter describes straightforward methods to check and adjust calibrations for the most common meteorological instruments – precipitation (rainfall), temperature, humidity and air pressure sensors. To reduce uncertainty in the measurements themselves, meteorological instruments need to be accurately calibrated, or at least regularly compared against instruments of known calibration to quantify and adjust for any differences, or error. Calibrations can and do drift over time, and therefore instrumental calibrations should be checked regularly, and adjusted if necessary.

There are enormous differences in functionality and capability between basic and advanced weather stations. This chapter outlines typical system specifications within broad capability and budget boundaries. When used with the prioritized assessments of functionality from the previous chapter, it will provide clearer guidance regarding the main brands, products and suppliers within the automatic weather station sectors.

In order to provide representative measurements of precipitation (rainfall, snow and hail, drizzle, sleet and so on), measuring devices must be deployed in suitable locations or sites and the instruments themselves exposed to the weather conditions they are intended to measure in a standardised manner. This chapter sets out what those standardised conditions of site and exposure are for measurements of precipitation, following the guidelines laid down by the World Meteorological Organization in the so-called CIMO guide (Commission for Instruments and Methods of Observation). Both manual and automated (recording) raingauge measurements are covered in detail, including tipping bucket, ground flush or pit gauges and weighing gauges, together with methods to decrease losses due to wind. Snowfall measurement methods are also covered.

There are many different varieties of automatic weather stations (AWSs) available, and a huge range of different applications for them. This chapter suggests a structured approach to specifying AWS features to meet any particular requirement, provides a short guide to AWS products and services available (from consumer brands to sophisticated professional systems capable of unattended operation in remote areas) and offers guidance in selecting one or more options from the multiplicity of product offerings on the market.

As the hydrologic cycle is driven by it, precipitation must be considered its main component: without precipitation, there is also not much of a hydrologic cycle. Precipitation naturally follows supersaturation of the air, usually as a result of cooling. One of the most effective ways of cooling occurs through lifting of the air mass, often involving a cyclonic motion. Most precipitation weather systems can be classified according to their type of cyclonic motion. For many hydrologic applications it is necessary to consider not only the spatial but also the temporal distribution of the precipitation, and many procedures are available for this purpose. The part of precipitation that moistens the surface elements, and is temporarily stored on them, is referred to as interception; often also called interception loss, it can amount to as much as 30 to 40% of the precipitation in dense forests. Detailed energy-budget considerations show that snow melt is mainly driven by the air temperature above freezing. Most past records of precipitation suffer from substantial systematic error. The main factor is wind. Different measurement techniques have been proposed to solve this problem.

Planting trees to increase rain was the grand climate controversy of the nineteenth century. Some European scientists with diverse backgrounds in physics, meteorology, forests, and soils developed a new science of forest meteorology that blended meteorology, forest ecology, and forest hydrology. They sought answers in direct measurement of forest influences on climate and installed meteorological observatories in forested and open lands to obtain the necessary data. They explained forest influences in the laws of physics, fused with interdisciplinary knowledge of meteorology, forest hydrology, and forest ecology, and gathered the data to further their theories. It was an understanding based on observations of microclimates, but upon which was layered a dynamical framework applicable to macroclimates. Many of the findings have withstood the test of time, and the questions posed are still relevant to today’s scientists.

The period from the mid-nineteenth century to the end of the century saw heightened interest in the harmful effects of deforestation on rain. There was growing fear that deforestation was turning prosperous lands into deserts, accompanied by efforts to conserve remaining forests or replant denuded lands. In India, Australia, New Zealand, South Africa, Russia, and the United States, the cry was raised: forests must be protected and managed for rain. These efforts followed prior concern in France and British island possessions. In this, forest conservationists advanced a need for government control of forests and used forest influences on rainfall as justification. Opponents, in turn, attacked the premise of forest influences on rainfall and decried the lack of evidence for climate deterioration. The ensuing debate was a narrative of misunderstanding, misuse of data, and hyperbole. It is this aspect of the forest–climate question, the so-called desiccation theory and its misuse to achieve policy goals, that has formed the historiography of the controversy, but beneath the rhetoric is found a fledgling knowledge of forest influences on climate that can be seen in today’s science.

Counter to the science of forest meteorology, prominent meteorologists in the United States held that climate was unchanged despite more than two centuries of forest clearing. In examining patterns of temperature and precipitation, they could not find a signal of forest influences, and their theories of large-scale atmospheric dynamics, likewise, did not accommodate forests. It was this idea that American meteorologists embraced as the forest-rainfall controversy exploded onto the public consciousness. Finding no evidence of climate change where there had been deforestation, they dismissed the idea that forests influence climate. Their voices prevailed, but the dismissal of forest influences proved to be too rigid. The science rose again in the latter half of the twentieth century as atmospheric scientists considered anthropogenic climate change. In developing their theories and mathematical models of climate, these scientists discovered that they needed to account for forests and other vegetation. The science of forest-climate influences, so resoundingly rejected at the turn of the twentieth century, has now been reinvented as forests are again seen as a means to improve climate.

Another long-standing convention links forests with rainfall. The plentiful rainfall in the Americas was associated with the thick forests, and deforestation was thought to reduce rain. A similar belief unfolded elsewhere in the world, and conservationists reframed the forest-climate question from one of deforesting the land to make a more temperate climate to one of preserving forests and planting trees to protect the supply of water. In rainfall, conservationists found a way to convey the environmental destruction wrought by deforestation. The scientific basis for forest influences on rain was found in new knowledge of stomata, transpiration, and photosynthesis. Eighteenth- and nineteenth-century naturalists sought further evidence for changes in rainfall in the flow of water in streams and rivers. Interception of rainwater by the leaves in forest canopies, infiltration into the soil, runoff over the ground, and evaporation from the soil were identified as key determinants of streamflow. A backlash arose, however, as the nineteenth century lengthened and the advocacy of forests galvanized into a worldwide campaign for forest conservation and tree planting to enhance rainfall.