El Niño Southern Oscillation (ENSO) and Health: An Overview for Climate and Health Researchers <s> Introduction <s> The Southern Oscillation (Variability of the Tropical Atmosphere). Oceanic Variability in the Tropics. Oceanic Adjustment. I. Oceanic Adjustment. II. Models of Tropical Atmosphere. Interactions between the Ocean and Atmosphere. Bibliograpy. <s> BIB001 </s> El Niño Southern Oscillation (ENSO) and Health: An Overview for Climate and Health Researchers <s> Introduction <s> El Niño Southern Oscillation (ENSO) is a climate event that originates in the Pacific Ocean but has wide-ranging consequences for weather around the world, and is especially associated with droughts and floods. The irregular occurrence of El Niño and La Niña events has implications for public health. On a global scale, the human effect of natural disasters increases during El Niño. The effect of ENSO on cholera risk in Bangladesh, and malaria epidemics in parts of South Asia and South America has been well established. The strongest evidence for an association between ENSO and disease is provided by time-series analysis with data series that include more than one event. Evidence for ENSO's effect on other mosquito-borne and rodent-borne diseases is weaker than that for malaria and cholera. Health planners are used to dealing with spatial risk concepts but have little experience with temporal risk management. ENSO and seasonal climate forecasts might offer the opportunity to target scarce resources for epidemic control and disaster preparedness. <s> BIB002 </s> El Niño Southern Oscillation (ENSO) and Health: An Overview for Climate and Health Researchers <s> Introduction <s> AFFILIATIONS: KucharsKi—international centre for Theoretical physics, earth system physics section, Trieste, italy; Kang—seoul national University, seoul, Korea; straus—center for oceanland-Atmosphere studies, George mason University, Fairfax, Virginia; King—monash University, Jalan lagoon selatan, Bandar sunway, malaysia CORRESPONDING AuThOR: Fred Kucharski, The Abdus salam international centre for Theoretical physics, earth system physics section, Trieste, italy e-mail: kucharsk@ictp.it <s> BIB003 </s> El Niño Southern Oscillation (ENSO) and Health: An Overview for Climate and Health Researchers <s> Introduction <s> [1] The atmosphere, hydrosphere, and cryosphere form a fully coupled climate system. This system exhibits a number of large‒scale phenomena, such as the El Nino–Southern Oscillation, the Asian Monsoon, the North Atlantic Oscillation, and the Madden‒Julian Oscillation. While these modes of variability are not exactly periodic, they are oscillatory in character, and their state is monitored using so‒called climate indices. Each of these scalar indices is a combination of several climate variables. Here we use a comprehensive set of 25 climate indices for time intervals that range between 1948 and 2011 and estimate an optimal set of lags between these indices to maximize their correlation. We show that most of the index pairs drawn from this set present a significant correlation on interannual time scales. It is also shown that on average, about two thirds of the total variability in each index can be described by using only the four leading principal components of the entire set of lagged indices. Our index set's leading orthogonal modes exhibit several interannual frequencies and capture separately variability associated with the North Atlantic and the North Pacific. These modes are associated, in turn, with large‒scale variations of sea surface temperatures. <s> BIB004 </s> El Niño Southern Oscillation (ENSO) and Health: An Overview for Climate and Health Researchers <s> Introduction <s> Climate risk management has emerged over the last decade as a distinct area of activity within the wider field of climatology. Its focus is on integrating climate and non-climate information in order to enhance the decision-making process in a wide range of climate-sensitive sectors of society, the economy and the environment. Given the burgeoning pure and applied climate science literature that addresses a range of climate risks, the purpose of this progress report is to provide an overview of recent developments in the field of climatology that may contribute to the risk assessment component of climate risk management. Data rescue and climate database construction, hurricanes and droughts as examples of extreme climate events and seasonal climate forecasting are focused on in this report and are privileged over other topics because of either their fundamental importance for establishing event probability or scale of societal impact. The review of the literature finds that historical data rescue, climate... <s> BIB005
Through a cascade of processes that link variability in the ocean-atmosphere system and the surface environment, weather and climate can have a discernible impact on health. Such impacts may be direct, indirect or diffuse  and occur over a range of temporal and spatial scales BIB005 . There is a burgeoning literature on the assessment of the impacts of climate on health, generally focusing on the health risks of climate variability and climate change. The climate variability and health literature is generally concerned with establishing the impact on health of variations in weather conditions at intra-seasonal, inter-annual, and interdecadal time periods. In general, climatic variability is connected with variations in the state of the atmospheric and ocean circulation and land surface properties (e.g. soil moisture) at the intra-seasonal to inter-decadal timescales. Therefore, climate variability and health studies explore relationships between historical climate and health data at a variety of temporal and spatial scales. Climate change-related health studies generally focus on the risks of a systematic change in the statistical properties of climate (e.g. mean and variance) over a prolonged period (e.g. several decades and beyond). Projections of the health risks of climate change use established associations, often derived from quantifications of associations between health outcomes and climate variability, and 'force' these with projected changes in climate variables to make projections about the possible outcomes arising from anthropogenic climate change. Assessments of the health risks of climate change rely on both known associations between health and climate variability, and on projections of how the magnitude and pattern of risks could change with additional climate change. Therefore, it is important to understand the range of modes of climate variability, generally defined as quasi-periodic variations in ocean and atmospheric circulation patterns that possess an oscillatory behaviour, that might influence health. A large number of modes of climate variability have been identified {3, BIB004 BIB003 , all of which could be considered as potential drivers of intra-seasonal to inter-annual to interdecadal variability in health outcomes (Table 1) . Table 1 A major driver of inter-annual climate variability associated with adverse health outcomes is the El Niño Southern Oscillation (ENSO) phenomenon BIB002 . ENSO can account for a considerable proportion of climate variance across a range of geographical scales [Wang, 2012] and thus impact health sensitive environmental conditions, including land-and oceanbased temperature and precipitation extremes, ecosystem health, drought and riverine and coastal flooding. Because strong ENSO-related climate anomalies have discernible impact on health in some regions and because ENSO generally accounts for the largest proportion of the inter-annual variation in climate BIB001 , especially in regions where health systems are less resilient to 'climate shocks', the purpose of this paper is to present an overview of the basic characteristics of the ENSO phenomenon and its climate impacts, discuss the use of ENSO indices in climate and health research and outline our present understanding of ENSO health associations. ENSO-based seasonal health forecasting and the possible impacts of climate change on ENSO and the implications this holds for future assessments of ENSO health associations will also be briefly discussed.