Toward a Quantitative Estimate of Future Heat Wave Mortality under Global Climate Change

Background: Climate change is anticipated to affect human health by changing the distribution of known risk factors. Heat waves have had debilitating effects on human mortality, and global climate models predict an increase in the frequency and severity of heat waves. The extent to which climate change will harm human health through changes in the distribution of heat waves and the sources of uncertainty in estimating these effects have not been studied extensively. Objectives: We estimated the future excess mortality attributable to heat waves under global climate change for a major U.S. city. Methods: We used a database comprising daily data from 1987 through 2005 on mortality from all nonaccidental causes, ambient levels of particulate matter and ozone, temperature, and dew point temperature for the city of Chicago, Illinois. We estimated the associations between heat waves and mortality in Chicago using Poisson regression models. Results: Under three different climate change scenarios for 2081–2100 and in the absence of adaptation, the city of Chicago could experience between 166 and 2,217 excess deaths per year attributable to heat waves, based on estimates from seven global climate models. We noted considerable variability in the projections of annual heat wave mortality; the largest source of variation was the choice of climate model. Conclusions: The impact of future heat waves on human health will likely be profound, and significant gains can be expected by lowering future carbon dioxide emissions

Cancer Incidence among Former Love Canal Residents

Ba c k g r o u n d: The Love Canal was a rectangular 16-acre, 10-ft-deep chemical waste landfill situated in a residential neighborhood in Niagara Falls, New York. This seriously contaminated site came to public attention in 1978. Only one prior study examined cancer incidence in former residents of the Love Canal neighborhood (LC). Objective: In this study we aimed to describe cancer incidence in former LC residents from 1979 to 1996 and to investigate whether it differs from that of New York State (NYS) and Niagara County (NC). Me t h o d s: From 1978 to 1982, we interviewed 6,181 former residents, and 5,052 were eligible to be included in this study. In 1996, we identified 304 cancer diagnoses in this cohort using the NYS Cancer Registry. We compared LC cancer incidence with that of NYS and NC using standardized incidence ratios (SIRs), and we compared risks within the LC group by potential exposure to the landfill using survival analysis. Res u l t s: SIRs were elevated for cancers of the bladder [SIR NYS = 1.44; 95 % confidence interval (CI), 0.91–2.16] and kidney (SIR NYS = 1.48; 95 % CI, 0.76–2.58). Although CIs included 1.00, other studies have linked these cancers to chemicals similar to those found at Love Canal. We also found higher rates of bladder cancer among residents exposed as children, based on two cases. Co n c l u s i o n s: In explaining these excess risks, the role of exposure to the landfill is unclear given such limitations as a relatively small and incomplete study cohort, imprecise exposure measurements, and the exclusion of cancers diagnosed before 1979. Given the relatively young age of the cohort, further surveillance is warranted. Key w o r d s: cancer, community health, exposure assessment, hazardous waste sites, Love Canal. Environ Health Perspect 117:1265–1271 (2009). doi:10.1289/ehp.0800153 available vi

Observations of aerosols in the free troposphere and marine boundary layer of the subtropical Northeast Atlantic: discussion of processes determining their size distribution

During July 1994, submicron aerosol size distributions were measured at two sites on Tenerife, Canary Islands. One station was located in the free troposphere (FT), the other in the marine boundary layer (MBL). Transport toward these two sites was strongly decoupled: the FT was first affected by dust and sulfate-laden air masses advecting from North Africa and later by clean air masses originating over the North Atlantic, whereas the MBL was always subject to the northeasterly trade wind circulation. In the FT the submicron aerosol distribution was predominantly monomodal with a geometric mean diameter of 120 nm and 55 nm during dusty and clean conditions, respectively. The relatively small diameter during the clean conditions indicates that the aerosol originated in the upper troposphere rather than over continental areas or in the lower stratosphere. During dusty conditions the physical and chemical properties of the submicron aerosol suggest that it has an anthropogenic origin over southern Europe and that it remains largely externally mixed with the supermicron mineral dust particles during its transport over North Africa to Tenerife. Apart from synoptic variations, a strong diurnal variation in the aerosol size distribution is observed at the FT site, characterized by a strong daytime mode of ultrafine particles. This is interpreted as being the result of photoinduced nucleation in the upslope winds, which are perturbed by anthropogenic and biogenic emissions on the island. No evidence was found for nucleation occurring in the undisturbed FT. The MBL site was not strongly affected by European pollution during the period of the measurements. The MBL aerosol size distribution was bimodal, but the relative concentration of Aitken and accumulation mode varied strongly. The accumulation mode can be related to cloud processing of the Aitken mode but also to pollution aerosol which was advected within the MBL or entrained from the FT. No bursts of nucleation were observed within the MBL

Two configurations of the Western Arctic Shelfbreak Current in summer

Author Posting. © American Meteorological Society, 2012. This article is posted here by permission of American Meteorological Society for personal use, not for redistribution. The definitive version was published in Journal of Physical Oceanography 42 (2012): 329-351, doi:10.1175/JPO-D-11-026.1.Data from a closely spaced array of moorings situated across the Beaufort Sea shelfbreak at 152°W are used to study the Western Arctic Shelfbreak Current, with emphasis on its configuration during the summer season. Two dynamically distinct states of the current are revealed in the absence of wind, with each lasting approximately one month. The first is a surface-intensified shelfbreak jet transporting warm and buoyant Alaskan Coastal Water in late summer. This is the eastward continuation of the Alaskan Coastal Current. It is both baroclinically and barotropically unstable and hence capable of forming the surface-intensified warm-core eddies observed in the southern Beaufort Sea. The second configuration, present during early summer, is a bottom-intensified shelfbreak current advecting weakly stratified Chukchi Summer Water. It is baroclinically unstable and likely forms the middepth warm-core eddies present in the interior basin. The mesoscale instabilities extract energy from the mean flow such that the surface-intensified jet should spin down over an e-folding distance of 300 km beyond the array site, whereas the bottom-intensified configuration should decay within 150 km. This implies that Pacific Summer Water does not extend far into the Canadian Beaufort Sea as a well-defined shelfbreak current. In contrast, the Pacific Winter Water configuration of the shelfbreak jet is estimated to decay over a much greater distance of approximately 1400 km, implying that it should reach the first entrance to the Canadian Arctic Archipelago.This work was supported by National Science Foundation GrantsOCE-0726640,OPP-0731928, and OPP-0713250.2012-09-0

Centennial climate variability in the British Isles during the mid-late Holocene

Reproduced with permission of the publisher. Copyright © 2010 Elsevier LtdMulti-millennial climate changes were relatively minor over the mid–late Holocene in the British Isles, because orbitally forced insolation changes were smaller than those at higher latitudes. Centennial climate variability is thus likely to have exerted a greater influence on the environment and human society of the region. Proxy-climate records from the British Isles covering the last 4500 years are assembled and re-evaluated with the aim of identifying centennial climate variability reflected by multi-proxy indicators. The proxies include bog oak populations, peatland surface wetness, flooding episodes from fluvial deposits, speleothem annual band width and oxygen isotopes, chironomids from lake sediments and sand and dune deposition. Most proxies reflect water balance rather than temperature alone, and records predominantly reflect warm season climate. A series of 12 key periods of enhanced precipitation–evaporation (P-E) are identified by their presence in two or more proxy records. Variability in P-E is much greater than that shown by temperature proxies and there is no necessary association between warm/cool and dry/wet periods. Although the data for temperature are less robust than those for P-E, a series of key temperature changes are proposed based on speleothem δ18O and chironomid inferred July temperature records; relatively cool before c. 3100 years BP, warmer (3100–2000 years BP), cool (2000–1250 cal years BP), warm (1250–650 cal years BP), and cool (650 cal years BP onwards). Some key increases in P-E (2750, 1650, 550 cal years BP) show a strong correspondence with ‘Bond cycles’ in ocean proxy records for increased ice rafted debris, decreased summer sea surface temperatures and sometimes decreased North Atlantic deep water circulation. Other higher frequency changes in P-E are also strongly related to SST variability. Whilst some of the main changes to cooler SSTs and increased P-E are approximately coincident with reduced solar output, most are not and thus must be the result of the internal dynamics of the ocean and atmosphere. Future work should concentrate on firmly establishing the pattern of temperature change, improving chronological accuracy and precision in existing records and improving process-based understanding of proxies

Introducing the Green Protein Footprint method as an understandable measure of the environmental cost of anchovy consumption

In a global framework of growing concern for food security and environmental protection, the selection of food products with higher protein content and lower environmental impact is a challenge. To assess the reliability of different strategies along the food supply chain, a measure of food cost through the environmental impact-protein content binomial is necessary. This study proposes a standardized method to calculate the Green Protein Footprint (GPF) index, a method that assesses both the environmental impact of a food product and its protein content provided to consumers. Life Cycle Assessment (LCA) was used to calculate the environmental impact of the selected food products, and a Life Cycle Protein Assessment (LCPA) was performed by accounting for the protein content along the supply chain. Although the GPF can be applied to all food chain products, this paper is focused on European anchovy-based products for indirect human consumption (fishmeal) and for direct human consumption (fresh, salted and canned anchovies). Moreover, the circular economy concept was applied considering the valorization of the anchovy residues generated during the canning process. These residues were used to produce fishmeal, which was employed in bass aquaculture. Hence, humans are finally consuming fish protein from the residues, closing the loop of the original product life cycle. More elaborated, multi-ingredient food products (salted and canned anchovy products), presented higher GPF values due to higher environmental impacts. Furthermore, the increase of food loss throughout their life cycle caused a decrease in the protein content. Regarding salted and canned products, the packaging was the main hotspot. The influence of the packaging was evaluated using the GPF, reaffirming that plastic was the best alternative. These results highlighted the importance of improving packaging materials in food products.The authors thank the Ministry of Economy and Competitiveness of the Spanish Government for their financial support via the projects GeSAC-Conserva: Sustainable Management of the Cantabrian Anchovies (CTM2013-43539-R) and CERES_Project: Food Production strategies for climate change mitigation: towards a food circular economy (CTM 2016-76176-C2-1-R). Authors thank Julia Celaya for her technical support. Jara Laso thanks the Ministry of Economy and Competitiveness of Spanish Government for their financial support via the research fellowship BES-2014-069368

Is the northern high-latitude land-based CO2 sink weakening?

Author Posting. © American Geophysical Union, 2011. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Global Biogeochemical Cycles 25 (2011): GB3018, doi:10.1029/2010GB003813.Studies indicate that, historically, terrestrial ecosystems of the northern high-latitude region may have been responsible for up to 60% of the global net land-based sink for atmospheric CO2. However, these regions have recently experienced remarkable modification of the major driving forces of the carbon cycle, including surface air temperature warming that is significantly greater than the global average and associated increases in the frequency and severity of disturbances. Whether Arctic tundra and boreal forest ecosystems will continue to sequester atmospheric CO2 in the face of these dramatic changes is unknown. Here we show the results of model simulations that estimate a 41 Tg C yr−1 sink in the boreal land regions from 1997 to 2006, which represents a 73% reduction in the strength of the sink estimated for previous decades in the late 20th century. Our results suggest that CO2 uptake by the region in previous decades may not be as strong as previously estimated. The recent decline in sink strength is the combined result of (1) weakening sinks due to warming-induced increases in soil organic matter decomposition and (2) strengthening sources from pyrogenic CO2 emissions as a result of the substantial area of boreal forest burned in wildfires across the region in recent years. Such changes create positive feedbacks to the climate system that accelerate global warming, putting further pressure on emission reductions to achieve atmospheric stabilization targets.This study was supported through grants provided as part of the Arctic System Science Program (NSF OPP‐ 0531047), the North American Carbon Program (NASA NNG05GD25G), and the Bonanza Creek Long‐Term Ecological Program (funded jointly by NSF grant DEB‐0423442 and USDA Forest Service, Pacific Northwest Research Station grant PNW01‐JV11261952‐231)

Sensitivity of L-band vegetation optical depth to carbon stocks in tropical forests: a comparison to higher frequencies and optical indices

Supplementary data to this article can be found online at https://doi.org/10.1016/j.rse.2019.111303.Monitoring vegetation carbon in tropical regions is essential to the global carbon assessment and to evaluate the actions oriented to the reduction of forest degradation. Mainly, satellite optical vegetation indices and LiDAR data have been used to this purpose. These two techniques are limited by cloud cover and are sensitive only to the top of vegetation. In addition, the vegetation attenuation to the soil microwave emission, represented by the vegetation optical depth (VOD), has been applied for biomass estimation using frequencies ranging from 4 to 30¿GHz (C- to K-bands). Atmosphere is transparent to microwaves and their sensitivity to canopy layers depends on the frequency, with lower frequencies having greater penetration depths. In this regard, L-band VOD (1.4¿GHz) is expected to enhance the ability to estimate carbon stocks. This study compares the sensitivity of different VOD products (from L, C, and X-bands) and an optical vegetation index (EVI) to the above-ground carbon density (ACD). It quantifies the contribution of ACD and forest cover proportion to the VOD/EVI signals. The study is conducted in Peru, southern Colombia and Panama, where ACD maps have been derived from airborne LiDAR. Results confirm the enhanced sensitivity of L-band VOD to ACD when compared to higher frequency bands, and show that the sensitivity of all VOD bands decreases in the densest forests. ACD explains 34% and forest cover 30% of L-band VOD variance, and these proportions gradually decrease for EVI, C-, and X-band VOD, respectively. Results are consistent through different categories of altitude and carbon density. This pattern is found in most of the studied regions and in flooded forests. Results also show that C-, X-band VOD and EVI provide complementary information to L-band VOD, especially in flooded forests and in mountains, indicating that synergistic approaches could lead to improved retrievals in these regions. Although the assessment of vegetation carbon in the densest forests requires further research, results from this study support the use of new L-band VOD estimates for mapping the carbon of tropical forests.Peer ReviewedPostprint (author's final draft