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A new generation of an Earth System Model now includes a number of land surface processes directly relevant to analyzing potential impacts of climate change. This model, HadGEM2-ES, allows us to assess the impacts of climate change, multiple interactions, and feedbacks as the model is run. This paper discusses the results of century-scale HadGEM2-ES simulations from an impacts perspective--specifically, terrestrial ecosystems and water resources--for four different scenarios following the Representative Concentration Pathways (RCPs), being used for next assessment report of the Intergovernmental Panel on Climate Change (IPCC). Over the 21st Century, simulated changes in global and continential-scale terrestrial ecosystems due to climate change appear to be very similar in all 4 RCPs, even though the level of global warming by the end of the 21st Century ranges from 2°C in the lowest scenario to 5.5°in the highest. A warming climate generally favours broadleaf trees over needleleaf, needleleaf trees over shrubs, and shrubs over herbaceous vegetation, resulting in a poleward shift of temperate and boreal forests and woody tundra in all scenarios. Although climate related changes are slightly larger in scenarios of greater warming, the largest differences between scenarios arise at regional scales as a consequence of different patterns of anthropogenic land cover change. In the model, the scenario with the lowest global warming results in the most extensive decline in tropical forest cover due to a large expansion of agriculture. Under all four RCPs, fire potential could increase across extensive land areas, particularly tropical and sub-tropical latitudes. River outflows are simulated to increase with higher levels of CO2 and global warming in all projections, with outflow increasing with mean temperature at the end of the 21st Century at the global scale and in North America, Asia, and Africa. In South America, Europe, and Australia, the relationship with climate warming and CO2 rise is less clear, probably as a result of land cover change exerting a dominant effect in those regions. [ABSTRACT FROM AUTHOR]

Recent observations in the eastern tropical South Pacific (ETSP) demonstrated the key role of meso- and submesoscale processes (e.g. eddies) in shaping its hydrographic and biogeochemical properties. Off Peru, elevated primary production from coastal upwelling in combination with sluggish ventilation of subsurface waters fuels a prominent oxygen minimum zone (OMZ). Given that nitrous oxide (N2O) production/consumption processes on the water column are sensitive to oxygen (O2) concentrations, the ETSP is a region of particular interest to investigate its source-sink dynamics. To date, no detailed surveys linking mesoscale processes and N2O distributions as well as their relevance to nitrogen (N) cycling are available. In this study, we present the first measurements of N2O across three mesoscale eddies (two mode water or anticyclonic and one cyclonic) which were identified, tracked and sampled during two surveys carried out in the ETSP in November-December 2012. A "two peak" structure was observed for N2O, wherein the two maxima coincide with the upper and lower boundaries of the OMZ, indicating active nitrification and partial denitrification. This was further supported by the abundances of the key gene for nitrification amoA and the gene marker for N2O production during denitrification, nirS. Conversely, we found strong N2O depletion in the core of the OMZ (O2 < 5 μmol L-1) to be consistent with nitrite (NO2-) accumulation and low levels of nitrate (NO3-1), thus suggesting active denitrification. N2O depletion within the OMZ's core was substantially higher in the center of mode water eddies, supporting the view that eddy activity enhances N-loss processes off Peru, in particular near the shelf break where nutrient-rich, productive waters from upwelling are trapped before being transported offshore. Analysis of eddies during their propagation towards the open ocean showed that, in general, "aging" of mesoscale eddies tends to decrease N2O concentrations through the water column in response to reduced supply of material to fuel N-loss, although hydrographic variability might also significantly impact the pace of the production/consumption pathways for N2O. Our results demonstrate the relevance of mode water eddies for N2O distribution, thereby improving our understanding of the N-cycling processes, which are of crucial importance in times of climate change and ocean deoxygenation. [ABSTRACT FROM AUTHOR]

Changes in Southern Ocean (SO) phytoplankton distributions with future warming have the potential to significantly alter nutrient and carbon cycles as well as higher trophic level productivity both locally and throughout the global ocean. Here we investigate the response of SO phytoplankton productivity and biomass to 21st century climate change across the CMIP5 Earth System Model suite. The models predict a zonallybanded pattern of phytoplankton abundance and production changes within 4 regions: the subtropical (∼ 30° S to 40° S), transitional (∼ 40° S to 50° S), subpolar (∼ 50° S to 65° S) and Antarctic (south of ∼ 65° S) bands. We find that shifts in bottom-up variables (nitrate, iron, and light availability) drive changes in phytoplankton abundance and production on not only interannual, but also decadal and 100-year timescales: the timescales most relevant to climate change. Spatial patterns in the modeled mechanisms driving these biomass trends qualitatively agree with recent observations, though longer-term records are needed to separate the effects of climate change from those of interannual variability. Because much past observational work has focused on understanding the effects of the Southern Annular Mode (SAM) on biology, future work should attempt to quantify the precise influence of an increasingly positive SAM on SO biology within the CMIP5 models. Continued long-term in-situ and satellite measurements of SO biology are clearly needed to confirm model findings. [ABSTRACT FROM AUTHOR]

Atmospheric CO2 inversions estimate surface carbon fluxes from an optimal fit to atmospheric CO2 measurements, usually including prior constraints on the flux estimates. Eleven sets of carbon flux estimates are compared, generated by different inversions systems that vary in their inversions methods, choice of atmospheric data, transport model and prior information. The inversions were run for at least 5 yr in the period between 1990 and 2009. Mean fluxes for 2001-2004, seasonal cycles, interannual variability and trends are compared for the tropics and northern and southern extratropics, and separately for land and ocean. Some continental/basin-scale subdivisions are also considered where the atmospheric network is denser. Four-year mean fluxes are reasonably consistent across inversions at global/latitudinal scale, with a large total (land plus ocean) carbon uptake in the north (-3.3 PgCy-1 (±0.6 standard deviation)) nearly equally spread between land and ocean, a significant although more variable source over the tropics (1.6±1.0 PgCy-1) and a compensatory sink of similar magnitude in the south (-1.4±0.6 PgCy-1) corresponding mainly to an ocean sink. Largest differences across inversions occur in the balance between tropical land sources and southern land sinks. Interannual variability (IAV) in carbon fluxes is larger for land than ocean regions (standard deviation around 1.05 versus 0.34 PgCy-1 for the 1996-2007 period), with much higher consistency amoung the inversions for the land. While the tropical land explains most of the IAV (stdev ~0.69 PgCy-1), the northern and southern land also contribute (stdev ~0.39 PgCy-1). Most inversions tend to indicate an increase of the northern land carbon uptake through the 2000s (around 0.11 PgCy-1), shared by North America and North Asia. The mean seasonal cycle appears to be well constrained by the atmospheric data over the northern land (at the continental scale), but still highly dependent on the prior flux seasonality over the ocean. Finally we provide recommendations to interpret the regional fluxes, along with the uncertainty estimates. [ABSTRACT FROM AUTHOR]

Ocean heat content varies on a range of timescales. Traditionally the atmosphere is seen to dominate the oceanic heat content variability. However, this variability can be driven either by oceanic or atmospheric heat fluxes. To diagnose the relative contributions and respective timescales, this study uses a box model forced with output from an ocean general circulation model (OGCM) to investigate the heat content variability of the upper 800m of the subtropical North Atlantic from 26° N to 36° N. The ocean and air-sea heat flux data needed to force the box model is taken from a 19 yr (1988 to 2006) simulation performed with the 1/12° version of the OCCAM OGCM. The box model heat content is compared to the corresponding heat content in OCCAM for verification. The main goal of the study is to identify to what extent the seasonal to interannual ocean heat content variability is of atmospheric or oceanic origin. To this end, the box model is subjected to a range of scenarios forced either with the full (detrended) ocean and air-sea fluxes, or their deseasoned counterparts. Results show that in all cases, the seasonal variability is dominated by the seasonal component of the air-sea fluxes, which produce a seasonal range in mean temperature of the upper 800m of ˜0.42 °C. However, on longer timescales oceanic heat transport dominates, with changes of up to ˜0.30 °C over 4 yr. The technique is subsequently applied to observational data. For the ocean heat fluxes, we use data from the RAPID program at 26° N from April 2004 to January 2011. At 36° N heat transport is inferred using a linear regression model based on the oceanic low-frequency transport in OCCAM. The air-sea flux from OCCAM is used for the period 2004 to 2006 when the RAPID timeseries and the OCCAM simulation overlap, and a climatology is used for the air-sea flux from 2006 onwards. The results confirm that on longer (>2 yr) timescales the ocean dominates the ocean heat content variability, which is further verified using data from the ARGO project. This work illustrates that oceanic divergence significantly impacts the ocean heat content variability on timescales relevant for applications such as seasonal hurricane forecasts. [ABSTRACT FROM AUTHOR]

More reliable estimates of carbon (C) stock within forest ecosystems and C emission induced by deforestation are urgently needed to mitigate the effects of emissions on climate change. A process-based terrestrial biogeochemical model (VISIT) was applied to tropical primary forests of two types (a seasonal dry forest in Thailand and a rain-forest in Malaysia) and one agro-forest (an oil palm plantation in Malaysia) to estimate the C budget of tropical ecosystems, including the impacts of land-use conversion, in Southeast Asia. Observations and VISIT model simulations indicated that the primary forests had high photosynthetic uptake: gross primary production was estimated at 31.5-35.5 tCha-1 yr-1. In the VISIT model simulation, the rainforest had a higher total C stock (plant biomass and soil organic matter, 301.5 tCha-1) than that in the seasonal dry forest (266.5 tCha-1) in 2008. The VISIT model appropriately captured the impacts of disturbances such as deforestation and land-use conversions on the C budget. Results of sensitivity analysis implied that the ratio of remaining residual debris was a key parameter determining the soil C budget after deforestation events. The C stock of the oil palm plantation was about 46% of the rainforest's C at 30 yr following initiation of the plantation, when the ratio of remaining residual debris was assumed to be about 33%. These results show that adequate forest management is important for reducing C emission from soil and C budget of each ecosystem must be evaluated over a long term using both the model simulations and observations. [ABSTRACT FROM AUTHOR]

This paper analyses a series of high-quality continuous records from southeastern Africa to study the spatiotemporal patterning of Holocene hydroclimatic anomalies in the region. Results indicate dominant frequencies of variability at millennial time scales, and a series of anomalies broadly common to all records. Of particular interest, data from the southern Cape coast exhibit periods of wetter/drier conditions that are out of phase with the sites less than 150 km away in the adjacent interior, but in phase with sites in tropical regions over 1000 km to the northeast. To explain such spatial patterns and gradients, we propose that the Agulhas Current may be a critical vector by which tropical climatic signals are propagated along the littoral zone, exerting a dominant, highly localized influence on near-coastal environmental conditions. Limitations in the data available do not allow for a detailed examination of the climatic dynamics related to these phenomena, but this paper highlights a series of avenues for future research to clarify the spatial extent and stability of the patterns observed. [ABSTRACT FROM AUTHOR]

Climatic and anthropogenic changes cause the deprivation of distinct ecosystems in Costa Rica, transforming climatic, ecological, and geomorphic conditions. The high tropical biodiversity of Costa Rica and the tropics is suitable to improve the understanding of hydrogeomorphic process dynamics and to produce baseline data on past disasters in scarce-data regions. The principal motivation to connect natural hazards and dendrochronology on tropics is the desire to create methods that can reduce its exposure and vulnerability. The principal research aim of this study is to give reference data that can improve the understanding of hydrogeomorphic processes and to explore the potential of tropical trees in dendrochronological applications. This paper combines remote sensing, meteorological assessments, and dendrochronology analyses, hydraulic modelling, and risk assessments. This innovative research describes the reduced understanding in treering analysis in Costa Rica related with past disasters and their linkage to climate. This study will likely contribute to the implementation of new methodologies in disaster risk research, and it will promote future adaptation strategies in the most biodiverse region of the world. [ABSTRACT FROM AUTHOR]

This paper presents the findings of an outdoor thermal comfort study conducted in Hong Kong using longitudinal experiments-an alternative approach to conventional transverse surveys. In a longitudinal experiment, the thermal sensations of a relatively small number of subjects over different environmental conditions are followed and evaluated. This allows an exploration of the effects of changing climatic conditions on thermal sensation, and thus can provide information that is not possible to acquire through the conventional transverse survey. The paper addresses the effects of changing wind and solar radiation conditions on thermal sensation. It examines the use of predicted mean vote (PMV) in the outdoor context and illustrates the use of an alternative thermal index-physiological equivalent temperature (PET). The paper supports the conventional assumption that thermal neutrality corresponds to thermal comfort. Finally, predictive formulas for estimating outdoor thermal sensation are presented as functions of air temperature, wind speed, solar radiation intensity and absolute humidity. According to the formulas, for a person in light clothing sitting under shade on a typical summer day in Hong Kong where the air temperature is about 28°C and relative humidity about 80%, a wind speed of about 1.6 m/s is needed to achieve neutral thermal sensation. [ABSTRACT FROM AUTHOR]

Cattle ranchers and dairy farmers operating throughout many tropical regions are experiencing major challenges associated with climate change such as higher incidence of heat stress and drought. These effects can result in reduced productivity of rangeland, shortage of nutritional feed, increased heat stress on animals, and high energy costs for cooling. High temperatures and resultant heat stress reduce animal productivity and increase the proliferation and survival of parasites and disease pathogens. Warming reduces the ability of dairy cattle to produce milk and gain weight and can also lower conception rates. This paper reviews research from the Caribbean on heat tolerant traits in bovine and presents evidence that introducing a “slick hair” gene into Holstein cows by crossbreeding with Senepols may increase thermo-tolerance and productivity. As in other parts of the tropics, principal cattle breeds in Puerto Rico and the US Virgin Islands have been largely introduced from temperate regions. Research indicates these animals may be poorly adapted to rising temperatures, leaving them increasingly vulnerable to chronic heat stress and reduced productivity. Adaptive practices have been developed in breeding and pasture management programs including selection for more heat-resistant genotypes, silvopasturing and crop diversification in forage production, and optimizing facilities and practices to reduce heat stress. Given the nature of climate vulnerability, an integrated approach to adaptation will likely have the greatest success in reducing future risk for producers. [ABSTRACT FROM AUTHOR]

In a recent article, Li et al. examined changes in the summer-season location of the western ridge of the North Atlantic subtropical high from 1948 to 2007 because there has been an increase in interannual summer rainfall variability in the southeastern United States. The following major conclusions by Li et al. are incorrect: the western ridge has undergone a significant westward trend since the late 1970s; the western ridge had increased meridional movement during 1978-2007 compared to 1948-1977; and global warming appears to be contributing to the westward expansion of the western ridge. Results presented in this paper reveal that the western ridge has been moving eastward over the past three decades, there was no change in latitudinal variance, and a westward movement of the western ridge should not be linked to global warming. [ABSTRACT FROM AUTHOR]

In this paper, we evaluate several timely, daily air-sea heat flux products (NCEP, NCEP2, ERA-Interim and OAFlux/ISCCP) against observations and present the newly developed TropFlux product. This new product uses bias-corrected ERA-interim and ISCCP data as input parameters to compute air-sea fluxes from the COARE v3.0 algorithm. Wind speed is corrected for mesoscale gustiness. Surface net shortwave radiation is based on corrected ISCCP data. We extend the shortwave radiation time series by using 'near real-time' SWR estimated from outgoing longwave radiation. All products reproduce consistent intraseasonal surface net heat flux variations associated with the Madden-Julian Oscillation in the Indian Ocean, but display more disparate interannual heat flux variations associated with El Niño in the eastern Pacific. They also exhibit marked differences in mean values and seasonal cycle. Comparison with global tropical moored buoy array data, I-COADS and fully independent mooring data sets shows that the two NCEP products display lowest correlation to mooring turbulent fluxes and significant biases. ERA-interim data captures well temporal variability, but with significant biases. OAFlux and TropFlux perform best. All products have issues in reproducing observed longwave radiation. Shortwave flux is much better captured by ISCCP data than by any of the re-analyses. Our 'near real-time' shortwave radiation performs better than most re-analyses, but tends to underestimate variability over the cold tongues of the Atlantic and Pacific. Compared to independent mooring data, NCEP and NCEP2 net heat fluxes display ~0.78 correlation and >65 W m rms-difference, ERA-I performs better (~0.86 correlation and ~48 W m) while OAFlux and TropFlux perform best (~0.9 correlation and ~43 W m). TropFlux hence provides a useful option for studying flux variability associated with ocean-atmosphere interactions, oceanic heat budgets and climate fluctuations in the tropics. [ABSTRACT FROM AUTHOR]

This paper describes seasonal peculiarities of modern climate warming in the European region. It is shown that warming scenarios considerably differ in cold and warm periods of the year. The warming is accompanied with growth and considerable change in the phase of the yearly cycle in solarity data. A strong half-year cycle is recognized in seasonal variation of long-term trends over the last few years. Peculiarities of climate change in Europe and the increased influence of the tropics are discussed in view of the results obtained. [ABSTRACT FROM AUTHOR]

This data paper reports litter fall data collected in a network of 21 forest sites in Japan. This is the largest litter fall data set freely available in Japan to date. The network is a part of the Monitoring Sites 1000 Project launched by the Ministry of the Environment, Japan. It covers subarctic to subtropical climate zones and the four major forest types in Japan. Twenty-three permanent plots in which usually 25 litter traps were installed were established in old-growth or secondary natural forests. Litter falls were collected monthly from 2004, and sorted into leaves, branches, reproductive structures and miscellaneous. The data provide seasonal patterns and inter-annual dynamics of litter falls, and their geographical patterns, and offer good opportunities for meta-analyses and comparative studies among forests. [ABSTRACT FROM AUTHOR]

The article discusses "The Impact of Climate Change on Global Tropical Cyclone Damage," a study published by researchers at Yale University and the Massachusetts Institute of Technology (MIT). According to the article, the research focused on forecasting the potential economic impact of global tropical storms through the year 2100. Comments from study author Robert Mendelsohn, an economist, are highlighted.

As is true of many tropical regions, northeastern Puerto Rico is an ecologically sensitive area with biological life that is highly elevation dependent on precipitation and temperature. Climate change has the potential to increase the risk of losing endemic species and habitats. Consequently, it is important to explore the pattern of trends in precipitation and temperature along an elevation gradient. Statistical derivatives of a frequently sampled dataset of precipitation and temperature at 20 sites along an elevation gradient of 1000 m in northeastern Puerto Rico were examined for trends from 2001 to 2013 with nonparametric methods accounting for annual periodic variations such as yearly weather cycles. Overall daily precipitation had an increasing trend of around 0.1 mm day−1 yr−1. The driest months of the annual dry, early, and late rainfall seasons showed a small increasing trend in the precipitation (around 0.1 mm day−1 yr−1). There was strong evidence that precipitation in the driest months of each rainfall season increased faster at higher elevations (0.02 mm day−1 more increase for 100-m elevation gain) and some evidence for the same pattern in precipitation in all months of the year but at half the rate. Temperature had a positive trend in the daily minimum (around 0.02°C yr−1) and a negative trend in the daily maximum whose size is likely an order of magnitude larger than the size of the daily minimum trend. Physical mechanisms behind the trends may be related to climate change; longer-term studies will need to be undertaken in order to assess the future climatic trajectory of tropical forests. [ABSTRACT FROM AUTHOR]

Worldwide, the rapid shrinking of glaciers in response to ongoing climate change is modifying the glacial meltwater contribution to hydrosystems in glacierized catchments. Determining the influence of glacial runoff to streams is therefore of critical importance to evaluate potential impact of glacier retreat on water quality and aquatic biota. This task has challenged both glacier hydrologists and ecologists over the last 20 yr due to both structural and functional complexity of the glacier-stream system interface. Here we propose quantifying the diurnal cycle amplitude of the streamflow to determine the glacial influence in glacierized catchments. We performed water-level measurements using water pressure loggers over 10 months at 30 min time steps in 15 stream sites in 2 glacier-fed catchments in the Ecuadorian Andes (> 4000 ma.s.l.) where no perennial snow cover is observed outside the glaciers. For each stream site, we performed wavelet analyses on water-level time series, determined the scale-averaged wavelet power spectrum at 24 h scale and defined three metrics, namely the power, frequency and temporal clustering of the diurnal flow variation. The three metrics were then compared to the percentage of the glacier cover in the catchments, a metric of glacial influence widely used in the literature. As expected, we found that the diurnal variation power of glacier-fed streams decreased downstream with the addition of non-glacial tributaries. We also found that the diurnal variation power and the percentage of the glacier cover in the catchment were significantly positively correlated. Furthermore, we found that our method permits the detection of glacial signal in supposedly non-glacial sites, thereby revealing glacial meltwater resurgence. While we specifically focused on the tropical Andes in this paper, our approach to determine glacial influence may have potential applications in temperate and arctic glacierized catchments. The measure of diurnal water amplitude therefore appears as a powerful and cost-effective tool to understand the hydrological links between glaciers and hydrosystems better and assess the consequences of rapid glacier shrinking. [ABSTRACT FROM AUTHOR]

Recently Diem questioned the western ridge movement of the North Atlantic subtropical high (NASH) reported in a 2011 paper of Li et al. This reply shows more analysis that further strengthens the conclusions originally put forth by Li et al. Diem''s analysis of the trend in the western ridge of the NASH was based on the data over a 30-yr period (1978-2007), whereas the main conclusions in Li et al. were drawn according to the data over a 60-yr period (1948-2007). Over the last 60 years, the NASH has shown a significant trend of westward movement, the meridional movement of the western ridge of the NASH has enhanced in the recent three decades, and the potential impact of global warming cannot be ruled out in an attempt to explain these changes of the NASH. [ABSTRACT FROM AUTHOR]

Abstract: As is well known, the quasi-biennial oscillation (QBO) of wind in the equatorial stratosphere has a significant influence on the processes not only at tropical but also at middle and high latitudes in both stratosphere and troposphere. Consequently, a forecasting the dates of QBO-phase (W or E) transitions is required for the solution of many problems (for instance, for investigation of possible climate changes, for studying of solar activity effects in atmospheric phenomena, for predicting the trends of various atmospheric parameters, etc.). The type of QBO-phase is commonly determined by the zonal wind direction at fixed altitude. The quasi-biennial alternations of wind direction are related with a successive descent of easterly and westerly wind regimes. The paper describes the peculiarities of the wind evolution during QBO-cycle and reveals that the easterly regime propagates downward always with stop at some altitude in the range 20–40hPa. This time period (no less than three months) of the easterly descent interruption is termed as the stagnation stage. Seasonal regularities of stagnation stage cause the discreteness of QBO-cycle period. If the interval between beginnings of successive stagnation stages is identified as a QBO-cycle length, it appears that no QBO-period other than 24, 30, or 36 months can be realized. The QBO-cycle period is unambiguously related with the stagnation duration that allows making an early forecast of the QBO-phase transition dates. The paper discusses the stagnation stage features occurring during QBO-cycles of different period, and describes the technique of forecasting the QBO-cycle evolution by analyzing the vertical profiles of wind speed. The study is based on experimental observation of zonal wind in the equatorial stratosphere during 1953–2011. It is shown that the previous quasi-biennial cycle has begun in January 2009, lasted for 30 months and completed in June 2011. The current cycle has begun in July 2011, will last for 30 months and will end in December 2013. Subsequent cycle will begin in January 2014. The QBO-phase transition dates for different height levels are determined for all months up to April 2014. [Copyright &y& Elsevier]

A reanalysis of the Atlantic basin tropical storm and hurricane database ('best track') for the period from 1921 to 1930 has been completed. This reassessment of the main archive for tropical cyclones of the North Atlantic Ocean, Caribbean Sea, and Gulf of Mexico was necessary to correct systematic biases and random errors in the data as well as to search for previously unrecognized systems. The methodology for the reanalysis process for revising the track and intensity of tropical cyclone data has been detailed in a previous paper on the reanalysis. The 1921-30 dataset now includes several new tropical cyclones, excludes one system previously considered a tropical storm, makes generally large alterations in the intensity estimates of most tropical cyclones (both toward stronger and weaker intensities), and typically adjusts existing tracks with minor corrections. Average uncertainty in intensity and track values is estimated for both open-ocean conditions as well as landfalling systems. Highlights are given for changes to the more significant hurricanes to impact the United States, Central America, and the Caribbean for this decade. [ABSTRACT FROM AUTHOR]

By comparison with the Northern Hemisphere, there is a paucity of high-resolution, continuous records extending into the Last Glacial Maximum from the Southern Hemisphere. With specific reference to coastal eastern Australia, there are long records of paleoclimatic and paleoenvironmental variability available from the tropical north and temperate south. However, there are significant spatial gaps between such records: in particular, until relatively recently, little attention had been paid to the subtropics. This review paper summarises understanding of regional paleoenvironmental and paleoclimatic variability in coastal eastern Australia during the termination of the Last Glacial Stage, with the aim of highlighting gaps in the current state of knowledge. Recommendations for future research are prioritised to answer knowledge gaps in understanding climate variability in eastern Australia between ca 33-18 kyr BP. [ABSTRACT FROM AUTHOR]

Observations have indicated a trend of freshwater loss in the global western boundary current extension regions over several recent decades. In this paper, the coupled ocean--atmosphere response to the observed freshwater flux trend [[defined as evaporation minus precipitation (EmP)]] over the Kuroshio--Oyashio Extension (KOE) region is studied in a series of coupled model experiments. The model explicitly demonstrates that the positive EmP forcing in the KOE region can set up a cyclonic gyre straddling the subtropical and the subpolar gyre, which induces anomalous southward cold advection in the west and northward warm advection in the interior. This leads to the formation of a temperature dipole in the midlatitudes with a cooling in the west and a warming in the east. With the positive EmP forcing in the KOE, the response of the extratropical atmospheric circulation in the North Pacific sector is characterized by an equivalent barotropic low originating primarily from the western tropical Pacific changes and countered by the extratropical SST forcing. The positive EmP forcing also strengthens the tropical zonal SST gradient and thus ENSO through several competing processes including the surface-coupled wind--evaporative--SST (WES) mechanism, subduction of extratropical warm anomalies, and spinup of the density-driven meridional overturning circulation. Applications to recent Pacific climate changes are discussed. [ABSTRACT FROM AUTHOR]

•The rich ecology of tropical forests is intimately tied to their moisture status. Multi-site syntheses can provide a macro-scale view of these linkages and their susceptibility to changing climates. Here, we report pan-tropical and regional-scale analyses of tree vulnerability to drought. •We assembled available data on tropical forest tree stem mortality before, during, and after recent drought events, from 119 monitoring plots in 10 countries concentrated in Amazonia and Borneo. •In most sites, larger trees are disproportionately at risk. At least within Amazonia, low wood density trees are also at greater risk of drought-associated mortality, independent of size. For comparable drought intensities, trees in Borneo are more vulnerable than trees in the Amazon. There is some evidence for lagged impacts of drought, with mortality rates remaining elevated 2 yr after the meteorological event is over. •These findings indicate that repeated droughts would shift the functional composition of tropical forests toward smaller, denser-wooded trees. At very high drought intensities, the linear relationship between tree mortality and moisture stress apparently breaks down, suggesting the existence of moisture stress thresholds beyond which some tropical forests would suffer catastrophic tree mortality. [ABSTRACT FROM AUTHOR]

South American subtropics east of the Andes exhibit a region of intense climatological frontogenesis in equivalent potential temperature (EPT) in the December to March season, mostly produced by deformation of the wind field. The goal of this paper is to investigate the large scale features associated with intense and weak frontogenesis by deformation (FGD) in EPT in the region where it attains its climatological maximum. This can be approximately delimited by 32-42° S and 66-69°W, which is small enough as to contain only one synoptic perturbation at a time. The spatial average of the positive values of frontogenesis at 850 hPa over the whole region (DFG+) is used to represent the strength of the perturbation. ECMWF ERA-40 reanalysis data set is used to calculate DFG+ at six hour intervals for 21 seasons (1981-2002). Compositing analysis is carried out for strong (above the 0.75 quantile) and weak (below the 0.25 quantile) events. For strong events the geopotential field at 850 hPa exhibits the North Argentinean Low (NAL), a transient trough and the Low Pressure Tongue East of the Andes (LPT). Upon comparison with the composite field of FGD it can be observed that FGD exhibits a strong maximum over the Argentinean Col (AC) which separates the NAL and the trough. These features are absent in the weak frontogenesis composite, which exhibits a stronger South Pacific Subtropical High close to the continent. At 250 hPa the strong FGD composite exhibits a trough over the Andes with a wind speed maximum to its east. Both of these features are associated with the deepening of the NAL in the literature. These are not present in the weak FGD composites. Strong events show an intense quasi meridional corridor of water vapor transport from the Amazon to the subtropics that encounters westerly flow in the neighborhood of the AC. This is absent in weak events. A preliminary analysis of precipitation is carried out using the GPCP daily data set. An intense precipitation nucleus appears slightly northeast of the AC, with maximum intensity in the day that follows the strong events. Weak events exhibit a drying of the subtropics instead, between one and three days after the events. Higher precipitation over the oceanic South Atlantic Convergence Zone can be also observed. Analogous composites were constructed for the presence and absence of both the AC and the LPT, showing similar characteristics to the strong and weak FGD event composites respectively, but with lower intensities. This shows that by selecting strong FGD events, intense NAL and LPT events are also singled out. [ABSTRACT FROM AUTHOR]

The origins of tourism and the foundations of tourism scholarship arc in the temperate zones of the globe. While tropical destinations and themes have not been ignored in tourism study, a closer focus on the commonalities of tropical tourism settings is warranted. The defining common physical and social features of tropical locations include climate, political history and often modest levels of development. The perceptions of the tropics by external powers have also shaped the development of the region. The tourism related consequences of these features are distinctive patterns in seasonality, challenges in managing highly similar destination images and an array of natural and social resources which pose common management problems. Building on this context, the core aim of this paper is to encourage better benchmarking information for understanding and managing tourism in the tropics. The paper seeks to fulfil this aim both by outlining research topics to assist the management of tropical tourism and by using the tropics as a rich canvas for new directions in tourism study. Additionally, the role of tourism research in addressing pressing issues for the tropics is noted. Throughout, it is argued that there is much to be gained by more comparative studies of tourism processes and systems within tropical settings. [ABSTRACT FROM AUTHOR]

This paper explores changes in the principal components of observed energy budgets across the tropical Pacific in response to the strong 1998 El Niño event. Multisensor observations from the Tropical Rainfall Measuring Mission (TRMM) Microwave Imager (TMI), Visible and Infrared Scanner (VIRS), and precipitation radar (PR) instruments aboard TRMM are used to quantify changes in radiative and latent heating in the east and west Pacific in response to the different phases of the El Niño–Southern Oscillation. In periods of normal east–west SST gradients there is substantial heating in the west Pacific and cooling in the east, implying strong eastward atmospheric energy transport. During the active phase of the El Niño, both the east and west Pacific tend toward local radiative–convective equilibrium resulting in their temporary energetic decoupling. It is further demonstrated that the response of these regions to ENSO-induced SST variability is directly related to changes in the characteristics of clouds and precipitation in each region. Through quantitative analysis of the radiative and latent heating properties of shallow, midlevel, and deep precipitation events and an equivalent set of nonprecipitating cloud systems, times of reduced atmospheric heating are found to be associated with a shift toward shallow and midlevel precipitation systems and associated low-level cloudiness. The precipitation from such systems is typically less intense, and they do not trap outgoing longwave radiation as efficiently as their deeper counterparts, resulting in reduced radiative and latent heating of the atmosphere. The results also suggest that the net effect of precipitating systems on top-of-the-atmosphere (TOA) fluxes and the efficiency with which they heat the atmosphere and cool the surface exhibit strong dependence on their surroundings. The sensitivity of cloud radiative impacts to the atmospheric and surface properties they act to modify implies the existence of strong feedbacks whose representation may pose a significant challenge to the climate modeling community. [ABSTRACT FROM AUTHOR]

This paper examines the potential of the stable isotopic ratios, 18O/16O (δ 18Oice) and 2H/1H (δ Dice), preserved in mid to low latitude glaciers as a tool for paleoclimate reconstruction. Ice cores are particularly valuable as they contain additional data, such as dust concentrations, aerosol chemistry, and accumulation rates, that can be combined with the isotopic information to assist with inferences about the regional climate conditions prevailing at the time of deposition. We use a collection of multi-proxy ice core histories to explore the δ 18O-climate relationship over the last 25,000 years that includes both Late Glacial Stage (LGS) and Holocene climate conditions. These results suggest that on centennial to millennial time scales atmospheric temperature is the principal control on the δ 18Oice of the snowfall that sustains these high mountain ice fields. Decadally averaged δ 18Oice records from three Andean and three Tibetan ice cores are composited to produce a low latitude δ 18Oice history for the last millennium. Comparison of this ice core composite with the Northern Hemisphere proxy record (1000–2000 A.D.) reconstructed by Mann et al. (1999) and measured temperatures (1856–2000) reported by Jones et al. (1999) suggests the ice cores have captured the decadal scale variability in the global temperature trends. These ice cores show a 20th century isotopic enrichment that suggests a large scale warming is underway at low latitudes. The rate of this isotopically inferred warming is amplified at higher elevations over the Tibetan Plateau while amplification in the Andes is latitude dependent with enrichment (warming) increasing equatorward. In concert with this apparent warming, in situ observations reveal that tropical glaciers are currently disappearing. A brief overview of the loss of these tropical data archives over the last 30 years is presented along with evaluation of recent changes in mean δ 18Oice composition. The isotopic composition of precipitation should be viewed not only as a powerful proxy indicator of climate change, but also as an additional parameter to aid our understanding of the linkages between changes in the hydrologic cycle and global climate. [ABSTRACT FROM AUTHOR]

The present study investigates the impact of northern mid-winter major stratospheric warming on tropical convection over the Indian region by examining the five Mid-winter Major Stratospheric Warming (MSW) events 2003/04, 2005/06, 2008/09, 2012/13, and 2018/19. The dynamical variables like temperature, wind components, and Outgoing Longwave Radiation are utilized from ECMWF ERA-Interim Reanalysis and NOAA site. Eliassen Palm (E-P) flux is used to visualize the upward and equator-ward propagation of extratropical Planetary Waves (PWs) from the lower atmosphere and their reach to the tropical region. The dominance of extratropical PW forcing from high to low latitudes is seen in all mid-winter cases. Further, the transfer of PW energy to low latitudes modifies the convection pattern over the Indian region. The author found depleted convection in the latitude band -15-20oN for the MSW 2003/04 and 2018/19, with frequent changes seen during MSW 2012/13 and 2005/06. On the other hand, the MSW 2008/09 show enhanced convection in the entire latitude band 20oS-20oN. This work suggests that the modification of OLR depends on the PW energy, onset time, peak temperature, and wind-reversed state during MSW. [ABSTRACT FROM AUTHOR]

In many countries, the natural phenomenon of lightning has been studied taking an account climatic and physiographic conditions. The atmospheric discharges are responsible for the death of more than 6000 people per year in the world. Colombia is located in the intertropical convergence zone and it has a geography characterized by plains and long mountain ranges. These conditions make Colombia located in the region with the highest lightning activity in the world increasing, increasing the number of deaths and injuries by this phenomenon, especially in rural zones. This paper presents a study about the total number of deaths and the mortality rate by lightnings for the period between 1997 and 2014. The information about deaths by lightning was taken from the statistics of the National Administrative Department of Statistics (Departamento Administrativo Nacional de Estadísticas - DANE). The obtained results are synthesized for all country and are discriminated by departments and natural subregions. In this way, the mortality rate obtained for Colombia was 1.51 per million people per year. Likewise, Vichada was the department with the highest mortality rate (7.85), while Popayan Plateau was the natural subregion with the highest number of deaths per million people per year with 8.62. [ABSTRACT FROM AUTHOR]

This paper uses new, high resolution satellite-derived data to explore recent cross-national differences in expanding tree cover. Increases in tree cover have concentrated in nations with recent histories of extensive deforestation, humid climates, high crop yields, and small numbers of farm workers. The associations of expanded tree cover with high yields for cereal crops and small populations of cultivators suggests a dynamic, sometimes referred to as a forest transition, in which urbanization and industrialization promote a long-term expansion in tree cover on certain types of land. The association of tree cover gains with tree cover losses and humid climates suggests a second dynamic, a churning, treadmill-like production of wood products from lands subjected to recurring harvests of wood products followed by tree cover gains in the recently harvested areas. The forest transition dynamic suggests that many smallholders would allow tree cover to expand on their lands if payments for environmental services were available. The salience of the treadmill dynamic of tree cover losses followed by tree cover gains underscores the importance of questions about the implications of commercial tree monocultures for biodiversity, carbon sequestration, and social justice. [ABSTRACT FROM AUTHOR]

This paper reports the nightglow observations of OI 630.0nm emissions, made by using all sky imager operating at low latitude station Kolhapur (16.8°N, 74.2°E and dip lat. 10.6°N) during high sunspot number years of 24th solar cycle. The images are analyzed to study the nocturnal, seasonal and solar activity dependence occurrence of plasma bubbles. We observed EPBs in images regularly during a limited period 19:30 to 02:30LT and reach maximum probability of occurrence at 22:30LT. The observation pattern of EPBs shows nearly no occurrence during the month of May and it maximizes during the period October–April. The equinox and solstice seasonal variations in the occurrence of plasma bubbles show nearly equal and large differences, respectively, between years of 2010–11 and 2011–12. [ABSTRACT FROM AUTHOR]

The general features of occurrence of an additional layer on the bottom side of F region, referred to as F0.5 layer in the pre noon period, over the magnetic equatorial location of Trivandrum (8.5°N; 77°E; dip lat of 0.5°N) in India during the period from 2004 to 2007 are presented using ionosonde observations. The F0.5 layer has a June (northern summer) solsticial maximum probability of occurrence with secondary maxima during December (northern winter) solstice. The seasonal as well as the day-to-day variability in the occurrence of F0.5 layer as mentioned in this paper seems to be a result of the variations in the amplitude and phases of the tides and gravity waves, and inventory of the metallic ions of meteoric origin. This study brings out an important manifestation of morning time F layer base region dynamics. [ABSTRACT FROM AUTHOR]

An improved method for predicting slant path attenuation in tropical climates is presented in this paper. The proposed approach is based on rain intensity data R0.01 (mm/h) from 37 tropical and equatorial stations; and is validated by using the measurement data from a few localities in tropical climates. The new method seems to accurately predict the slant path attenuation in tropical localities, and the comparative tests seem to show significant improvement in terms of the RMS of the relative error variable compared to the RMS obtained with the SAM, Crane, and ITU-R prediction models. [ABSTRACT FROM AUTHOR]

To assess the variation in distribution, extent, and NPP of global natural vegetation in response to climate change in the period 1911–2000 and to provide a feasible method for climate change research in regions where historical data is difficult to obtain. In this research, variations in spatiotemporal distributions of global potential natural vegetation (PNV) from 1911 to 2000 were analyzed with the comprehensive sequential classification system (CSCS) and net primary production (NPP) of different ecosystems was evaluated with the synthetic model to determine the effect of climate change on the terrestrial ecosystems. The results showed that consistently rising global temperature and altered precipitation patterns had exerted strong influence on spatiotemporal distribution and productivities of terrestrial ecosystems, especially in the mid/high latitudes. Ecosystems in temperate zones expanded and desert area decreased as a consequence of climate variations. The vegetation that decreased the most was cold desert (18.79%), while the maximum increase (10.31%) was recorded in savanna. Additionally, the area of tundra and alpine steppe reduced significantly (5.43%) and were forced northward due to significant ascending temperature in the northern hemisphere. The global terrestrial ecosystems productivities increased by 2.09%, most of which was attributed to savanna (6.04%), tropical forest (0.99%), and temperate forest (5.49%). Most NPP losses were found in cold desert (27.33%). NPP increases displayed a latitudinal distribution. The NPP of tropical zones amounted to more than a half of total NPP, with an estimated increase of 1.32%. The increase in northern temperate zone was the second highest with 3.55%. Global NPP showed a significant positive correlation with mean annual precipitation in comparison with mean annual temperature and biological temperature. In general, effects of climate change on terrestrial ecosystems were deep and profound in 1911–2000, especially in the latter half of the period. [ABSTRACT FROM AUTHOR]

Climate change has created potential major threats to global biodiversity. The multiple components of climate change are projected to affect all pillars of biodiversity, from genes over species to biome level. Of particular concerns are ―tipping points‖ where the exceedance of ecosystem thresholds will possibly lead to irreversible shifts of ecosystems and their functioning. As biodiversity underlies all goods and services provided by ecosystems that are crucial for human survival and wellbeing, this paper presents potential effects of climate change on biodiversity, its plausible impacts on human society as well as the setting in addressing a global crisis. Species affected by climate change may respond in three ways: change, move or die. Local species extinctions or a rapidly affected ecosystem as a whole respectively might move toward its particular ―tipping point‖, thereby probably depriving its services to human society and ending up in a global crisis. Urgent and appropriate actions within various scenarios of climate change impacts on biodiversity, especially in tropical regions, are needed to be considered. Foremost a multisectoral approach on biodiversity issues with broader policies, stringent strategies and programs at international, national and local levels is essential to meet the challenges of climate change impacts on biodiversity. [ABSTRACT FROM AUTHOR]

Abstract: Large quantities of archeology and literature records indicate that during the Shang Dynasty and a part of the Zhou Dynasty of Chinese history, about 2000 BC to 1000 BC, there once were wild elephants living in North China. For a long time, it was believed that all of these elephants belonged to the species Elephas maximus. Many scholars suggested that this phenomenon could show a much higher temperature at that time. However, as the research of Chinese historical climate has already indicated, even in the Megathermal Maximum, most of the parts of North China were still controlled by the climate of the Warm Temperate Zone, not the Subtropic Zone. This paper presents evidence suggesting that the so-called “wild elephants” in North China during that time belonged to Palaeoloxodon sp., not E. maximus. [Copyright &y& Elsevier]

Abstract: In subtropical Hong Kong, buildings consume the most of the electricity use. Computer simulation technique is a useful tool for predicting building thermal and energy performance. Simulation computer programs require weather data input to drive the mathematical models within the simulation tools for comparative studies and annual energy estimation. Typical weather year data representing the long-term climatic conditions are often used. Recently, there has been an increasing interest in incorporating daylight in the architectural and building designs to reduce building energy consumption. However, daylight parameters are not always available. In 2003, the International Commission on Illumination (CIE) adopted a range of 15 standard skies covering probably the whole spectrum of the usual skies in the world. Once the skies have been identified, the basic solar irradiance and daylight illuminance at various inclined planes can be obtained. This paper presents the work on the development and evaluation of two typical weather datasets, namely Typical Meteorological Year (TMY) and Test Reference Year (TRY). Measured hourly weather data for the 30-year period from 1979 to 2008 were analysed. Building energy simulations were conducted to evaluate the two weather datasets. Daylight parameters were derived using luminous efficacy approach and the sky conditions were categorized based on common climatic variables. [Copyright &y& Elsevier]

Globally, water resources for cities are under increasing stress. Two main stressors are climate change and population growth, but evaluating their relative impact is difficult, especially because of the complex topology of water supply. This is especially true in the tropical Andes, which is a region with strong climatic gradients and topographical limits to water resources. This paper presents an evaluation of both stressors on water resources in a geospatial framework to identify gradients in water availability that may lead to conflicts over water use. We focus on four major cities in, or receiving water from, the tropical Andes. A multimodel data set of 19 climate models is used as input for a regional water balance model. Per capita water availability is evaluated along topographic gradients for the present and for future scenarios of population growth and climate change. In all cases, the median projection of climate change suggests a relatively limited impact on water availability, but uncertainties are large. Despite these uncertainties, we find that the expected demographic changes are very likely to outpace the impact of climate change on water availability and should therefore be the priority for local policy making. However, distinctive geospatial patterns characterize the supply systems of the studied cities, highlighting the need to analyze the topology of water supply within an ecosystem services context. Our approach is flexible enough to be extended to other regions, stressors and water resources topologies. [ABSTRACT FROM AUTHOR]

Abstract: The keynote paper by Garrett Hardin 44years ago introduced the term ‘tragedy of the commons’ into our language (); this term is now used widely, but it is neither universally accepted nor fully understood. Irrespective, the ‘tragedy of the commons’ is an increasing reality for more than 500 million people that rely on the biodiversity resources and services of tropical coral reefs, mangrove forests, seagrass beds and associated fisheries. These natural resources continue to decline despite major advances in our scientific understanding of how ecosystems and human populations interact, and the application of considerable conservation and management efforts at scales from local user communities to oceans. Greater effort will be required to avert increasing damage from over-exploitation, pollution and global climate change; all deriving from increasing exploitation driven by poverty and progress i.e. continuing to expand development indefinitely and extraction of resources at industrial scales. However, the ‘tragedy’ concept has been widely criticized as a simple metaphor for a much larger set of problems and solutions. We argue that the ‘tragedy’ is essentially real and will continue to threaten the lives of millions of people unless there are some major moral and policy shifts to reverse increasing damage to coastal habitats and resources. We agree with the conclusion by Hardin that the solution to the tragedy will not be through the application of natural sciences, but via implementing exceedingly difficult and controversial moral decisions. An extreme example of a moral and controversial direction suggested by Hardin was in re-examining the ‘freedom to breed’ as an inherent human value. The need for ‘moral decisions’ is even greater in 2012. [Copyright &y& Elsevier]

Abstract: Hainan province is the only tropical and island province in China, with the unique climatic and geographical features. It has a different energy performance in public buildings from those in the inland areas. This paper investigated the current situation of energy consumption of the sampled public buildings, including 26 hotels, 24 office buildings and 7 department stores, through analyzing utility billing data, on-site survey and measurement, and site operational records. The breakdowns of energy consumption found out that the electricity dominated the energy consumption for all the sampled buildings and the air conditioning system played a key role in the energy consumption of major building services. By analyzing the main factors for building energy consumption, the annual average energy use indexes were calculated to be 141.63kWh/m2, 87.70kWh/m2, and 166.95kWh/m2 for hotels, office buildings and department stores, respectively. Besides, the comparison between Hainan province and other areas revealed that the building energy consumption of this tropical province was at a low level. Because indoor environment quality can influence the health and work efficiency of humans in buildings, field tests on the indoor environment quality were also carried out, and the performance of indoor environment quality was rated. [Copyright &y& Elsevier]

Abstract: The paper gives an analysis of the pattern of soil cover of the Sierra Madre del Sur, one of the most complex physiographic regions of Mexico. It presents the results of the study of four latitudinal traverses across the region. We show that the distribution of soils in the Sierra Madre del Sur is associated with major climatic gradients, namely by vertical bioclimatic zonality in the mountains and by the effect of mountain shadow. Altitudinal distribution of soil-bioclimatic belts is complex due to non-uniform gradients of temperature and rainfall, and varies with the configuration of the mountain range. The distribution of soils is associated with the erosion and accumulation rates both on mountain slopes and in river valleys. The abundance of poorly developed soils in (semi)arid areas was ascribed to high erosion rate rather than to low pedogenetic potential. The formation of soil mosaic at a larger scale might be ascribed to the complex net of gully erosion and to the system of seismically triggered landslides of various ages. In the valleys, the distribution of soils depends upon the dynamics of sedimentation and erosion, which eventually exposes paleosols. Red-colored clayey sediments are remains of ancient weathering and pedogenesis. Their distribution is associated mainly with the intensity of recent slope processes. The soil cover pattern of the Sierra Madre del Sur cannot be explained by simplified schemes of bioclimatic zonality. The soil ranges can be explained by the distribution of climates, lithology, complex geological history of the region, and recent geomorphological processes. [Copyright &y& Elsevier]

Abstract: Although considerable progress towards reducing tropical climate biases in the tropical Pacific has been made in many current-generation of climate models over the past decades, reducing large biases and maintaining good agreement with the observations in the tropical Atlantic is still a major challenge and this deficiency may seriously degrade the credibility of the models in their simulation and projection of future climate change in the Atlantic sector. In this paper, we show that the bias in the eastern equatorial Atlantic has a major effect on sea-surface temperature (SST) response to a rapid change in the Atlantic Meridional Overturning Circulation (AMOC). By comparing identical water hosing experiments conducted with two different coupled general circulation models, we dissect oceanic mechanisms underlying the difference in models'' SST response. The results show that the different SST response is plausibly attributed to systematic differences in the simulated tropical Atlantic ocean circulation. Therefore, in order to accurately simulate past abrupt climate changes and project future changes, the bias in climate models must be reduced. [Copyright &y& Elsevier]

Internationally, agriculture is widely regarded as one of the sectors at most risk from a changing climate. This is due to the impact of increased temperatures, reduced rainfall and increased frequency of extreme events, not only in the tropics but also in temperate environments. In the UK, growers also face a range of 'non-climate' risks, which, it is often argued, present a potentially greater and more immediate threat to sustainable food production than climate change. This paper highlights the climate and non-climate impacts on crop production, the adaptation options and the institutional and regulatory barriers to their uptake by farmers. It concludes that there are likely to be both positive impacts (for example, yield gains) and negative impacts (for example, increased water stress). Either way, there will be a need for new investments in adaptive management and technology, including new collaborations between the public and private sectors, to enable UK agriculture to respond to the potential effects of climate change. [ABSTRACT FROM AUTHOR]

Abstract: Tropical forests hold several goods and services used by forest-dependent people as safety nets to traverse difficult periods of resource supply. These same goods and services are constantly surrounded by emerging markets linking remote communities with major urban centers nationally and internationally. How these markets affect adaptation remains unclear. This paper examines the roles of markets in non-timber forest products that normally serve as safety nets for forest communities, and the implications for climate change adaptation in the Congo Basin. Following the identification and prioritization of forest-based development sectors for adaptation by stakeholders, the types of markets and trades surrounding the identified sectors were examined in two provinces in the Democratic Republic of Congo as a case study in order to evaluate revenue flows and their potential contribution to adaptation by local communities. The distribution of the market revenue leaves local people with returns much lower than the worth of the commodity, while wholesalers and retailers reap most of the benefits and profit from the high variability in volume and market earnings for the same commodity across provinces. Markets may increase the value of a commodity as observed in this study, but their contributions to adaptation appear highly limited for local communities following their distribution among the stakeholders in the market chain. This is likely to be worse in free market settings, especially when it diminishes the safety net roles of forest goods and services. Markets should therefore complement rather than substitute forests roles for adaptation to climate change in tropical forest countries. Capturing the benefits of trade for adaptation is crucial but will require policy reforms and further research that addresses the complexity in benefit sharing. [ABSTRACT FROM AUTHOR]

Abstract: The ecological consequences of climate change for large tropical forests such as the Amazon are likely to be profound. Amazonian forests strongly influence regional and global climates and therefore any changes in forest structure, such as deforestation or die-back, may create positive feedback on externally forced climate change. Monitoring, modelling and managing the impacts of anthropogenic climate change on forest dynamics is therefore an important objective of forest researchers, and one that requires long-term data on changes at the level of community, populations and phenotypes. In this paper we provide the most comprehensive study yet on the seasonal dynamics of various leaf traits: leaf area index (LAI), leaf mortality (LM), leaf biomass (LB), leaf growth rate (LG), and leaf residence time (TR) from 50 experimental plots in a forest site at Belterra, Pará State, Brazil. From this study we estimate annual mean leaf area index (LAI) to be 5.07m2 m−2 and annual mean leaf dry biomass to be 0.621kgm−2. The typical leaf grew at 0.049kgm−2 month−1 and remained on the tree for 12.7 months. We compare these results to other similar studies and critically discuss the factors driving leaf demographics in Amazonia. [Copyright &y& Elsevier]