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Towns and cities generally exhibit higher temperatures than rural areas for a number of reasons, including the effect that urban materials have on the natural balance of incoming and outgoing energy at the surface level, the shape and geometry of buildings, and the impact of anthropogenic heating. This localized heating means that towns and cities are often described as urban heat islands (UHIs). Urbanized areas modify local temperatures, but also other meteorological variables such as wind speed and direction and rainfall patterns. The magnitude of the UHI for a given town or city tends to scale with the size of population, although smaller towns of just thousands of inhabitants can have an appreciable UHI effect. The UHI “intensity” (the difference in temperature between a city center and a rural reference point outside the city) is on the order of a few degrees Celsius on average, but can peak at as much as 10°C in larger cities, given the right conditions. UHIs tend to be enhanced during heatwaves, when there is lots of sunshine and a lack of wind to provide ventilation and disperse the warm air. The UHI is most pronounced at night, when rural areas tend to be cooler than cities and urban materials radiate the energy they have stored during the day into the local atmosphere. As well as affecting local weather patterns and interacting with local air pollution, the UHI can directly affect health through heat exposure, which can exacerbate minor illnesses, affect occupational performance, or increase the risk of hospitalization and even death. Urban populations can face serious risks to health during heatwaves whereby the heat associated with the UHI contributes additional warming. Heat-related health risks are likely to increase in future against a background of climate change and increasing urbanization throughout much of the world. However, there are ways to reduce urban temperatures and avoid some of the health impacts of the UHI through behavioral changes, modification of buildings, or by urban scale interventions. It is important to understand the physical properties of the UHI and its impact on health to evaluate the potential for interventions to reduce heat-related impacts.

The European Alps have experienced remarkable climate changes since the beginning of the Industrial Age. In particular, mean air temperature in the region increased at a greater rate than global temperature, leading to the loss of nearly half of the glaciated area and to important changes in the ecosystems. Spanning 1,200 km in length, with peaks reaching over 4,000 meters above sea level (m asl), the Alps have a critical influence over the weather in most of Europe and separate the colder oceanic/continental climate in the north from the milder Mediterranean climate in the south. The climatic differences between the main slopes are reflected into different climate changes—whereas the northern slope got wetter, the southern slope got drier. The consequences of these climate changes are not confined to the Alpine region. Being located in the center of Europe, the Alps provide water and electricity for over 100 million people. Alpine run-off is a major contributor to the total discharge of several major European rivers such as the Rhine, the Rhône, the Po, and the Danube. Therefore, climate change in the Alps can have significant economic impacts on a continental scale. Their convenient geographical position allowed scientists to study the Alpine climate since the very beginning of the instrumental era. The first instrumental meteorological observations in an Alpine valley were taken as early as the mid-17th century, soon followed by measurements at higher elevations. Continuous records are available since the late 18th century, providing invaluable information on climate variability to modern-day researchers. Although there is overwhelming evidence of a dominant anthropogenic influence on the observed temperature increase, the causes of the changes that affected other variables have, in many cases, not been sufficiently investigated by the scientific community.

Climate change has resulted in rising global average temperatures and an increase in the frequency and intensity of extreme weather events, which already has and will yield serious public health consequences, including the risk of diarrheal diseases. Sufficient evidence in the literature has highlighted the association between different meteorological variables and diarrhea incidence. Both low and high temperatures can increase the incidence of diarrheal disease, and heavy rainfall has also been associated with increased diarrhea cases. Extreme precipitation events and floods are often followed by diarrhea outbreaks. Research has also concluded that drought can concentrate pathogens in water sources, which makes it possible for diarrhea pathogens to distribute broadly when the first heavy rain happens. Substantial evidence underscores the important role social, behavioral, and environmental factors may have for the climate-diarrhea relationship. Meteorological factors may further influence the social vulnerability of populations to diarrhea through a variety of social and behavioral factors. Future research should focus on social factors, population vulnerability, and further understanding of how climate change affects diarrhea to contribute to the development of targeted adaptation strategies.

Given the dire nature of many researchers’ predictions about the effects of global climate change (e.g., rising sea levels, droughts, more extreme weather), it comes as little surprise that less attention has been paid to the subtler, less direct outcomes of rapid climate change: psychological, sociological, political, and economic effects. In this chapter we explore one such outcome in particular: the effects of rapid climate change on aggression. We begin by exploring the potential for climate change to directly affect aggression in individuals, focusing on research showing the relationship between uncomfortably hot ambient temperature and aggression. Next, we review several lines of research illustrating ways that climate change can indirectly increase aggression in individuals. We then shift our focus from individuals to the effects of climate change on group-level aggression. We finish by addressing points of contention, including the challenge that the effects of climate change on aggression are too remote and too small to be considered relevant.

Beginning in the very earliest years of the space age, a flotilla of robotic explorers have been sent to study Mars—first simply to fly by, then to orbit, and, later, to attempt landing on the surface. For these landers, separating the rapidly approaching spacecraft from the surface is little but a tenuous carbon dioxide atmosphere, too thin to be useful but too thick to ignore. The purpose of the entry, descent, and landing (EDL) process is to take these hypersonic spacecraft through the approximately 6 mb atmosphere and place them safely on the Martian surface. The sequence of steps required to progressively slow and control this descending spacecraft has been honed throughout the decades but follows the same basic approach. A period of frictional deceleration during the entry phase of EDL first slows the spacecraft to a point where a supersonic parachute can be deployed to further slow the spacecraft during its descent phase. Whether a spacecraft is following a ballistic or a guided entry determines the need to control the downrange motion of the spacecraft during the entry phase, providing more or less targeting accuracy, at the expense of EDL complexity. The third and terminal EDL phase, consisting of a powered or semi-powered landing, brings the spacecraft to the surface. Over the years, a range of different powered landing approaches have been employed, from basic retropropulsion, to airbags to the SkyCrane, as spacecraft size has grown and landing sites have become more challenging. Despite this seemingly straightforward description, EDL at Mars is an exceptionally intricate process, with numerous failures over the decades; as of 2023, four space agencies have attempted, with varying degrees of success, to land on Mars. Environmental uncertainties during the EDL process typically remain a large mission concern. The process of characterizing the Martian atmosphere at the time, season, and location of touchdown has advanced incrementally from the earliest landings that relied on coarse orbital or flyby measurements of surface temperature and pressure to more modern efforts that incorporate sophisticated numerical models with high spatial and temporal resolution, pinpointing the most likely conditions that a spacecraft will experience during its traverse through the atmosphere and providing comprehensive uncertainty measurements to statistically bound the range of possible conditions. As spacecraft become more complex, it has become possible to add in situ sensors to the descending spacecraft to directly measure the local environment. Combined with numerical modeling and information provided by other spacecraft, these data have helped increase knowledge of the local environment to a substantial degree, reducing environmental uncertainty from being a major risk to a manageable concern.