Stroke burden in China has increased over the past 30 years, and remains particularly high in rural areas. There is a north-to-south gradient in stroke in China, with the greatest stroke burden observed in the northern and central regions.

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Heshang Cave is situated in central China (30º27'N, 110º25'E; 294 m) in the middle reaches of the Yangtze Valley, a region strongly impacted by the East Asian Monsoon. It contains large annually-laminated Holocene and late Pleistocene stalagmites which capture past monsoon behaviour with seasonal resolution, and could enhance understanding of the amplitude and frequency of monsoon behaviour in different climate states. In this paper, we present results of a 3-year monitoring programme at Heshang. T loggers outside the cave agree closely with T data from nearby meteorological stations. T at the site of growth of the largest recovered stalagmite averages 18ºC (identical to mean annual T outside the cave) with a seasonal amplitude of 5ºC (about one fifth of the external cycle). Rainfall measurements from a station 3 km from the cave indicate strong summer monsoon rain in 2004 and 2005, but rather weaker summer rain (by ≈30%) in 2006. Drip rate at the monitoring site has a base flow of 14 drips/minute and shows a sharp increase to ≈40 drips/minute early in the summer rains of 2004 and 2005, followed by a gradual return to base-flow as the monsoon weakens. This abrupt change presumably represents threshold behaviour in the hydrological system. This threshold is not passed in 2006 and there is no abrupt increase in drip rate, indicating the sensitivity of this site (and presumably of speleothem chemistry in this cave) to monsoon rainfall. Results are also reported from a 10-month deployment of a Stalagmate drip counter, and for CO 2 levels in Heshang Cave. Overall, this monitoring work represents an essential dataset for interpretation of the chemistry of drip waters, of carbonates grown on glass slides and, ultimately, of long speleothem records of past climate from Heshang Cave. February 2008 influences. High rainfall during strong monsoon years can lead to severe flooding, so prediction of the onset and strength of the monsoon is an important goal to aid in planning for agriculture and water resources. These scientific and societal goals amply justify the study of speleothem records from Central China and have motivated extensive work on a variety of Chinese caves in recent years (e.g. Wang et al., 2001 Wang et al., 2005 Hu et al., 2008). KeywordsHeshang (meaning "monk" in Mandarin Chinese) was first visited for scientific purposes in the late 1990s, and speleothem samples first recovered in 1998. Early work on these samples demonstrated the potential of the cave for reconstruction of the past East Asian monsoon at very high resolution for at least the last 20 kyr. Publications on the cave have, to date, established the chronology of two speleothems (Hu et al., 2005; 2008), investigated the use of dissolved Si as a paleo-proxy in speleothems (Hu et al., 2005), established a quantitative Holocene record of rainfall in Central China (Hu et al., 2008), and investigated the reconstruction of past climate at seasonal resolution using Heshang speleothems (Johnson et al., 2006).