Search Results

Unraveling the connections between meteorology, climate, and health—all broadly defined—is an endeavor that cuts across an astonishing array of times, places, and peoples. How societies pursue and interpret these connections is deeply tied to sociocultural, environmental, and political context. In the United States, meteorological beliefs rested on shared assumptions rooted in ancient traditions that linked prevailing environmental and climatic conditions with human health. By the 17th century, the steadfast collection of meteorological phenomena in weather journals was tethered to medical knowledge as well as the pursuit of agricultural, business, and shipping ventures. Environmental conditions were routinely theorized as causes for epidemics and individual sickness (or cure). As meteorology changed from a practice of data collection to a science over the 18th and 19th centuries, its medical arm branched into the interlocking fields of medical meteorology, medical climatology, and medical topography. However, even with the rise of new meteorological technologies and methods, older ways of knowing the weather persisted alongside formal medical theories of health and place, and tacit, embodied knowledge was never fully supplanted by instrumental data collection. The science of meteorology also grew into being as a tool of empire. Imperial states established networks of meteorological stations to collect weather data to further colonial ambitions and foster politically charged geographic imaginaries of colonized places and peoples. But theorizing the relationship between climate and health was not restricted to white men of science. Black intellectuals and subaltern peoples held radically different cosmologies of climate and challenged prevailing essentialist theories of climate and health throughout the 19th and 20th centuries. In the 20th century, scientists situated changing climates as a key dimension for disease patterns and demographic transition more broadly. As historians make use of the increasingly sophisticated methods of historical climatology, past climate reconstruction has sparked new questions on how environmental conditions have both enabled and constrained human action during climate—and political, infrastructural—disasters. New interdisciplinary approaches to the climate crisis have further offered ways to bridge the disconnect between climate science and medical practice that emerged during the 20th century.

West Africa is among the most populated regions of the world, and it is predicted to continue to have one of the fastest growing populations in the first half of the 21st century. More than 35% of its GDP comes from agricultural production, and a large fraction of the population faces chronic hunger and malnutrition. Its dependence on rainfed agriculture is compounded by extreme variations in rainfall, including both droughts and floods, which appear to have become more frequent. As a result, it is considered a region highly vulnerable to future climate changes. At the same time, CMIP5 model projections for the next century show a large spread in precipitation estimates for West Africa, making it impossible to predict even the direction of future precipitation changes for this region. To improve predictions of future changes in the climate of West Africa, a better understanding of past changes, and their causes, is needed. Long climate and vegetation reconstructions, extending back to 5−8 Ma, demonstrate that changes in the climate of West Africa are paced by variations in the Earth’s orbit, and point to a direct influence of changes in low-latitude seasonal insolation on monsoon strength. However, the controls on West African precipitation reflect the influence of a complex set of forcing mechanisms, which can differ regionally in their importance, especially when insolation forcing is weak. During glacial intervals, when insolation changes are muted, millennial-scale dry events occur across North Africa in response to reorganizations of the Atlantic circulation associated with high-latitude climate changes. On centennial timescales, a similar response is evident, with cold conditions during the Little Ice Age associated with a weaker monsoon, and warm conditions during the Medieval Climate Anomaly associated with wetter conditions. Land surface properties play an important role in enhancing changes in the monsoon through positive feedback. In some cases, such as the mid-Holocene, the feedback led to abrupt changes in the monsoon, but the response is complex and spatially heterogeneous. Despite advances made in recent years, our understanding of West African monsoon variability remains limited by the dearth of continuous, high- resolution, and quantitative proxy reconstructions, particularly from terrestrial sites.

In the years following the Second World War, the U.S. government played a prominent role in the support of basic scientific research. The National Science Foundation (NSF) was created in 1950 with the primary mission of supporting fundamental science and engineering, excluding medical sciences. Over the years, the NSF has operated from the “bottom up,” keeping close track of research around the United States and the world while maintaining constant contact with the research community to identify ever-moving horizons of inquiry. In the 1950s the field of meteorology was something of a poor cousin to the other branches of science; forecasting was considered more of trade than a discipline founded on sound theoretical foundations. Realizing the importance of the field to both the economy and national security, the NSF leadership made a concerted effort to enhance understanding of the global atmospheric circulation. The National Center for Atmospheric Research (NCAR) was established to complement ongoing research efforts in academic institutions; it has played a pivotal role in providing observational and modeling tools to the emerging cadre of researchers in the disciplines of meteorology and atmospheric sciences. As understanding of the predictability of the coupled atmosphere-ocean system grew, the field of climate science emerged as a natural outgrowth of meteorology, oceanography, and atmospheric sciences. The NSF played a leading role in the implementation of major international programs such as the International Geophysical Year (IGY), the Global Weather Experiment, the World Ocean Circulation Experiment (WOCE) and Tropical Ocean Global Atmosphere (TOGA). Through these programs, understanding of the coupled climate system comprising atmosphere, ocean, land, ice-sheet, and sea ice greatly improved. Consistent with its mission, the NSF supported projects that advanced fundamental knowledge of forcing and feedbacks in the coupled atmosphere-ocean-land system. Research projects have included theoretical, observational, and modeling studies of the following: the general circulation of the stratosphere and troposphere; the processes that govern climate; the causes of climate variability and change; methods of predicting climate variations; climate predictability; development and testing of parameterization of physical processes; numerical methods for use in large-scale climate models; the assembly and analysis of instrumental and/or modeled climate data; data assimilation studies; and the development and use of climate models to diagnose and simulate climate variability and change. Climate scientists work together on an array of topics spanning time scales from the seasonal to the centennial. The NSF also supports research on the natural evolution of the earth’s climate on geological time scales with the goal of providing a baseline for present variability and future trends. The development of paleoclimate data sets has resulted in longer term data for evaluation of model simulations, analogous to the evaluation using instrumental observations. This has enabled scientists to create transformative syntheses of paleoclimate data and modeling outcomes in order to understand the response of the longer-term and higher magnitude variability of the climate system that is observed in the geological records. The NSF will continue to address emerging issues in climate and earth-system science through balanced investments in transformative ideas, enabling infrastructure and major facilities to be developed.

Zhu Kezhen (1890–1974), also known as Chu Coching, was a Harvard-educated meteorologist who worked in the field of climate sciences in China from 1918 to 1974. He was highly regarded under vastly different political regimes. His concerns regarding the development of observatory networks, educational practices, and the establishment of research topics reflect the development of the field in China, which only began at the very end of the 19th century. Zhu Kezhen was influenced by the meteorological and climate knowledge imparted to him by his academic teachers in the United States and appropriated Ellsworth Huntington’s ideas on climate determinism, which shaped some of his fundamental concerns. One of his main achievements was to make use of a wide array of observational and other data in order to contribute to the “localization” of climate science. In fact, employing data culled from traditional sources and making use of and expanding the phenological knowledge of traditional Chinese rural society allowed him to approach climate science in a way that was not easily possible in the West. Zhu’s research into historical climate change in China embodied many aspects of his approach to the localization of science in China, but changes in the international scientific network (from an American-European to a Soviet-dominated network) and the political turmoil in the People’s Republic of China greatly impaired his work. Zhu’s research remains highly influential and has exerted considerable influence on environmental and climate history.