Projected Changes to Growth and Mortality of Hawaiian Corals over the Next 100 Years

BACKGROUND: Recent reviews suggest that the warming and acidification of ocean surface waters predicated by most accepted climate projections will lead to mass mortality and declining calcification rates of reef-building corals. This study investigates the use of modeling techniques to quantitatively examine rates of coral cover change due to these effects. METHODOLOGY/PRINCIPAL FINDINGS: Broad-scale probabilities of change in shallow-water scleractinian coral cover in the Hawaiian Archipelago for years 2000-2099 A.D. were calculated assuming a single middle-of-the-road greenhouse gas emissions scenario. These projections were based on ensemble calculations of a growth and mortality model that used sea surface temperature (SST), atmospheric carbon dioxide (CO(2)), observed coral growth (calcification) rates, and observed mortality linked to mass coral bleaching episodes as inputs. SST and CO(2) predictions were derived from the World Climate Research Programme (WCRP) multi-model dataset, statistically downscaled with historical data. CONCLUSIONS/SIGNIFICANCE: The model calculations illustrate a practical approach to systematic evaluation of climate change effects on corals, and also show the effect of uncertainties in current climate predictions and in coral adaptation capabilities on estimated changes in coral cover. Despite these large uncertainties, this analysis quantitatively illustrates that a large decline in coral cover is highly likely in the 21(st) Century, but that there are significant spatial and temporal variances in outcomes, even under a single climate change scenario

Displacement and Resettlement: Understanding the Role of Climate Change in Contemporary Migration

How do we understand displacement and resettlement in the context of climate change? This chapter outlines challenges and debates in the literature connecting climate change to the growing global flow of people. We begin with an outline of the literature on environmental migration, specifically the definitions, measurements, and forms of environmental migration. The discussion then moves to challenges in the reception of migrants, treating the current scholarship on migrant resettlement. We detail a selection of cases in which the environment plays a role in the displacement of a population, including sea level rise in Pacific Island States, cyclonic storms in Bangladesh, and desertification in West Africa, as well as the role of deforestation in South America’s Southern Cone as a driver of both climate change and migration. We outline examples of each, highlighting the complex set of losses and damages incurred by populations in each case

Sootshell formation in microgravity droplet combustion

The formation of the sootshell in microgravity droplet combustion can influence many aspects of droplet burning. Soot formation is believed to influence the burning rate through (1) changes in thermophysical properties since sootshell serves asa heat sink, (2) physical barrier effects as sootshell can reduce fuel mass flux, and (3) through reduction in the effective heat of combustion. In an effort to better understand the mechanism leading to sootshell formation, experiments were performed in the NASA 2.2 See droptower and JAMIC 10 See dropshaft. In these experiments, rapid insertion of a blunt plunger was used to blowoff the symmetric sootshell formed after the quasi- steady period. This allowed for the disruption of the original sootshell allowing for the observation of the re-formation of a new sootshell, from initiation near the flame followed by transport towards the equilibrium location. The measured sootshell velocity ( with nearly constant magnitude at the various radial position), which can be used to infer thermophoretic velocity, are similar in magnitude to the velocities of carbon particles measured in environments of imposed linear temperature profiles under microgravity conditions. These observations are in contrast to the recent modeling results that suggest photophoretic transport as an important mechanism in the transport of soot agglomerates