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Causes of the regional variability in observed sea level, sea surface temperature and ocean colour over the period 1993-2011
We analyse the regional variability in observed sea surface height (SSH), sea surface temperature (SST) and ocean colour (OC) from the ESA Climate Change Initiative (CCI) datasets over the period 1993-2011. The analysis focuses on the signature of the ocean large-scale climate fluctuations driven by the atmospheric forcing and do not address the mesoscale variability. We use the ECCO version 4 ocean reanalysis to unravel the role of ocean transport and surface buoyancy fluxes in the observed SSH, SST and OC variability. We show that the SSH regional variability is dominated by the steric effect (except at high latitude) and is mainly shaped by ocean heat transport divergences with some contributions from the surface heat fluxes forcing that can be significant regionally (confirming earlier results). This is in contrast with the SST regional variability, which is the result of the compensation of surface heat fluxes by ocean heat transport in the mixed layer and arises from small departures around this background balance. Bringing together the results of SSH and SST analyses, we show that SSH and SST bear some common variability. This is because both SSH and SST variability show significant contributions from the surface heat fluxes forcing. It is evidenced by the high correlation between SST and buoyancy forced SSH almost everywhere in the ocean except at high latitude. OC, which is determined by phytoplankton biomass, is governed by the availability of light and nutrients that essentially depend on climate fluctuations. For this reason OC show significant correlation with SST and SSH. We show that the correlation with SST display the same pattern as the correlation with SSH with a negative correlation in the tropics and subtropics and a positive correlation at high latitude. We discuss the reasons for this pattern
Long-term carbon sink in Borneo's forests halted by drought and vulnerable to edge effects
Less than half of anthropogenic carbon dioxide emissions remain in the atmosphere. While carbon balance models imply large carbon uptake in tropical forests, direct on-the-ground observations are still lacking in Southeast Asia. Here, using long-term plot monitoring records of up to half a century, we find that intact forests in Borneo gained 0.43 Mg C ha‾¹ per year (95% CI 0.14—0.72, mean period 1988-2010) above-ground live biomass. These results closely match those from African and Amazonian plot networks, suggesting that the world's remaining intact tropical forests are now en masse out-of-equilibrium. Although both pan-tropical and long-term, the sink in remaining intact forests appears vulnerable to climate and land use changes. Across Borneo the 1997-1998 El Niño drought temporarily halted the carbon sink by increasing tree mortality, while fragmentation persistently offset the sink and turned many edge-affected forests into a carbon source to the atmosphere
The analysis of fracture systems in subsurface thrust structures from the Foothills of the Canadian Rockies
Survey of surgical emergencies in a rural population in the Northern Areas of Pakistan
Objective: To determine the incidence of specific surgical emergencies in a mountainous rural community in the Northern Areas of Pakistan and to assess use of existing health services, and outcomes related to acute surgical illness events.METHOD: A cross-sectional population-based survey was conducted. Interviewers visited each of 118 villages in the study area (population 100000), selected a random sample from a total of 9900 households, and interviewed the oldest premenopausal female member (n = 836). Questions were focused on injury, acute abdomen, and/or maternal morbidity occurring in the past year. Cases were included as surgical emergencies when one or more index clinical features indicating a potential for surgical intervention were present. Mortality from a wider range of surgical emergencies was also elicited based on the respondent\u27s lifetime knowledge of the household.Results: The incidence rates were 1531/100000 persons per year for injuries; 1364/100000 for acute abdomen, and 16462/100000 for maternal morbidity. The rate of injuries was 2.7 times higher and that of acute abdomen twice as high in males as in females. The injury rate decreased with advancing age, being 13 times higher in children \u3c 5 years than in adults \u3e 40. By contrast, the rate for acute abdomen showed a rise with advancing age, being 8 times higher in the \u3e 40 age group than in under-fives. Burns, falls and road accidents, in that order, were the commonest forms of injury accounting for 82% of 138 cases. Of 43 burn casualties, 46% were in the age group \u3c 5 years; there was no gender bias. Of 71 casualties from falls and road accidents, 85% were aged 6-40 years; there was 6 : 1 male predominance. The maternal morbidity rate was highest in the age group 25-35 years and may be attributed to the high pregnancy rate in this age bracket. Of 408 patients with acute surgical illness, 85% were managed initially at home or close to home in a health centre, dispensary or civil hospital; 32% eventually sought specialist surgical care. The overall rate for minor and major surgical procedures was 411/100000 persons per year (lowest estimate), and appeared to be low. The rate of operative deliveries at 11.8/1000 deliveries (lowest estimate) was particularly low. The mortality rates were correspondingly high: 55/100000 persons per year for injuries and for acute abdomen (lowest estimates). The maternal mortality ratio was particularly high at 8.9/1000 deliveries (lowest estimate). Annual mortality rates derived from deaths recalled during the respondent\u27s lifetime in the household (mean period = 26 years), tended to corroborate the results of the 1-year survey.CONCLUSION: The incidence rates for broad categories of serious acute surgical illness in the study population far exceeded the rates of acute surgical intervention. Mortality rates were correspondingly high. Such evidence points to a large unmet surgical need and ought to spur improvements in the health service