Continental flood basalt weathering as a trigger for Neoproterozoic Snowball Earth

Atmospheric CO2 levels and global climate are regulated on geological timescales by the silicate weathering feedback. However, this thermostat has failed multiple times in Earth's history, most spectacularly during the Cryogenian (c. 720–635 Ma) Snowball Earth episodes. The unique middle Neoproterozoic paleogeography of a rifting, low-latitude, supercontinent likely favored a globally cool climate due to the influence of the silicate weathering feedback and planetary albedo. Under these primed conditions, the emplacement and weathering of extensive continental flood basalt provinces may have provided the final trigger for runaway global glaciation. Weathering of continental flood basalts may have also contributed to the characteristically high carbon isotope ratios (δ13C) of Neoproterozoic seawater due to their elevated P contents. In order to test these hypotheses, we have compiled new and previously published Neoproterozoic Nd isotope data from mudstones in northern Rodinia (North America, Australia, Svalbard, and South China) and Sr isotope data from carbonate rocks.The Nd isotope data are used to model the mafic detrital input into sedimentary basins in northern Rodinia. The results reveal a dominant contribution from continental flood basalt weathering during the ca. 130 m.y. preceding the onset of Cryogenian glaciation, followed by a precipitous decline afterwards. These data are mirrored by the Sr isotope record, which reflects the importance of chemical weathering of continental flood basalts on solute fluxes to the early–middle Neoproterozoic ocean, including a pulse of unradiogenic Sr input into the oceans just prior to the onset of Cyrogenian glaciation. Hence, our new data support the hypotheses that elevated rates of flood basalt weathering contributed to both the high average δ13C of seawater in the Neoproterozoic and to the initiation of the first (Sturtian) Snowball Earth

Towards a regional approach for animal health services provision and disaster risk reduction: the economics of the Caribvet network

31st West Indies Agricultural Economics Conference, August 10-14, 2015, Saint Croix, U.S. Virgin IslandsClimate change is expected to increase the frequency and intensity of natural disasters (Mechler et al. 2010) that impact the socio-economic development of nations worldwide, including those in the Caribbean, a region particularly vulnerable to natural perils (Macpherson and Akpinar-Elci, 2013). Global changes and climate change are also expected to have a significant impact on animal and human health, especially distribution and impact of vector-borne and zoonotic diseases which are considered particularly sensitive to climatic variables (Harvell et al. 2002). An integrated approach of disaster risk reduction (DDR) and climate change adaptation (CCA) has been suggested to avoid unnecessary duplication of efforts and to improve program effectiveness (Dwirahmadi et al. 2013). Consistent with the call of the World Organization of Animal Health (OIE), for reinforcing the role of veterinary authorities at national levels for disaster risk reduction (OIE and World Bank, 2007), a similar strategy is needed at the regional level in the Caribbean. In the Caribbean, veterinary services, agricultural and veterinary universities, research institutes, and regional and international institutions in agriculture and health have garnered efforts to create a regional animal health network (CaribVET) in 2006 to assist in decision making and to advise on best management practices to mitigate the impact of animal diseases on livestock production and health, human health and welfare. Since 2012, the Epidemiology working group of CaribVET works on DRR in close collaboration with CENSA, which is the OIE collaborating center on DRR in animal health in Cuba (Gongora et al. 2012). According to CENSA’s expertise, prevention and preparedness are the key components of the DRR cycle towards which CaribVET’s efforts should be oriented. In this paper, we propose a model that explains the economic rationale behind an animal health regional network as CaribVET. Then, the role of CaribVET in the improvement of knowledge on animal diseases, the development of tools that facilitates the provision of animal health, and the capacity development in the region is explained and associated to the well-known concepts of comparative advantages and economies of scale. We explain the role of CaribVET in DRR and the challenges to a regional approach on the deliverance of animal health services and DRR are discussed