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Coffee in the Central American region has played an increasingly important role in their economies and societies. For that reason, we have aimed to analyze the possible causes and impacts of the coffee rust outbreak 2012 in the coffee industry in Central America. We applied a descriptive approach, which is based on secondary data sources. Some of these sources are documents and reports published by OIC, USAD, PROMOCAFE and FAO. These reports are related to the coffee sector and the coffee rust outbreak 2012 in Central America Five countries were taken into account for this research; Honduras, Guatemala, El Salvador, Costa Rica and Nicaragua due to their importance in Central American coffee production. Several variables were collected and analyzed, these variables were: economic impacts, social impacts, the area affected by the coffee rust, farmers with less than 10 mzs, losses value caused by the leaf rust, per capital losses, exports and exports value from the five Central America countries. Two main causes caused this outbreak 2012 to be particularly catastrophic. (1) Climate changes: higher temperatures and high rainfall incidence for a long period triggered extensive coffee rust development and (2) declines in coffee prices in turn reduced the incentive for farmers to invest in the crop (including fungicides spraying, fertilizers applications and other cropping practices). This study also found possible reasons that influenced the coffee rust intensity in Central American countries including; cropping practices (fertilization and shade), coffee plant age and that the coffee rust has expanded at higher altitude (climate change). Which can be added to the overconfidence of the farmers and their lack of technical knowledge. The total economic losses for the region were 2,706,454 bags of 60 kilos in production losses, with US$ 499 Millions in foreign currency losses. In 2012, Coffee participation in GDP was reduced by 1.40% in Honduras, Guatemala 0.19%, El Salvador 0.31%, Nicaragua 0.53% and Costa Rica 0.03%. The social impacts caused by the coffee rust outbreak 2012 were critically included job losses of up to 12% in the region, coffee rust affected 55% of the surface planted in Central America, more than 80% of the farmers affected were smallholder farmers that live in the poorest areas in the region, this tended to diminish their nutritional status and health and increase food insecurity in the region. Our founding confirms countries with higher percentage of smallholder farmers had greater losses caused by the coffee rust outbreak 2012; these farmers are around 80%-96% of the total farmers in the Central America region. This is attributable to economic constrains, these smallholder farmers did not have the money to invest in the crop (Fertilization, pruning, cropping, etc.) due to the volatility in coffee prices and weak organization and structure of the coffee industry in the region. This outbreak revealed the weaknesses in the coffee industry in Central America, which brought up topics that were already evident in the rural areas such as high poverty rates, food insecurity, illiteracy, life quality and also the inefficiency in terms of adoption and technology transfers to the farmers. Governments need to strengthen the coffee industry through more effective and sustainable policies, especially targeting smallholder farmers focusing in strategies to unify these farmers through cooperatives and/or coffee associations to reduce vulnerabilities and give them the tools to work in a sustainable way as a coffee community and become a highly competitive and profitable industry.

A quarry failure along the slopes of the Wai Khar open-pit jade mine in Hpakant, Myanmar has led to the deaths of at least 172 jade miners on 2 July 2020. This paper conducts a systematic investigation of the incident by integrating data from multiple sensors, including high-resolution optical imagery, Sentinel-1 synthetic aperture radar (SAR) images, unmanned aerial system (UAS) footage, SRTM and ALOS digital elevation models (DEMs), soil moisture product from multi-spectral Landsat-8 satellite and precipitation records from the Climate Hazards Group InfraRed Precipitation with Station data (CHIRPS). Optical imagery, UAS footage and DEMs allow us to build a comprehensive mapping of tailing areas and quarry scarps from 2010 and reconstruct the 2D pit geometry prior to failure. Deformation signals from multi-temporal SAR interferometry (MTInSAR), soil moisture variations and precipitation trends further allow us to identify possible failure causes. To evaluate the quality of deformation obtained from different distributed-scatterer phase estimators, we develop an empirical mapping function based on areal fraction values to facilitate the comparison of temporal coherence values that are differently formulated in each phase estimator. The comparison shows that phase linking algorithm outperforms the small baseline subset method in terms of signal recovery and phase reliability. Our investigation points out that the mining site is under aggressive mining cycles that are exacerbated by frequent, uncontrolled landslides. Seepage failure, which involves the expulsion of water from rapidly compacting tailings, may be a critical factor in the 2020 incident. Instead of extreme weather, the failure had occurred under normal to drier conditions. This means that the sliding planes were already in a critical state, which is evident from the accelerated deformation around the collapse area since the beginning of 2020. Based on these findings, we provide recommendations to improve mining site regulations and management practices for safer open-pit mining in Myanmar and probably in similar contexts outside Myanmar. ? 2021 The Author(s)

Pelagic sediments recovered from the South China Sea (SCS) exhibit characteristic carbonate preservation fluctuations that are closely linked to major cycles of climatic change. Two deep sea cores (SCS 90-36: 17°59.70'N, 111°29.64'E, water depth 2050 m; and 31-KL: 18°45.4'N, 115°52.4'E, 3360 m) that are located respectively above and below the regional lysocline (~ 3000 m) were selected for studying the late Quaternary pattern of carbonate preservation in the SCS. Preservation indices measuring changes in the abundances of dissolution-resistant planktonic foraminifers and coccoliths, and in ratios of foraminiferal fragments, benthonic foraminifers, and radiolarians, have revealed increased carbonate preservation during the last glacial period and/or during the last deglaciation (Termination I; ~ 12,000 k.y.), but stronger carbonate dissolution during the interglacial period of the Holocene. Detailed comparisons of preservation and oxygen isotope records further indicate that the level of carbonate preservation increased steadily from 25 k.y. through Termination I and that preservation reached a maximum during Termination I. From Termination I into the Holocene, however, the level of preservation decreased gradually to a minimum. Both records exhibit noticeable glacial/interglacial variations (1/f on the order of 104 years), while the higher resolution record of 31-KL records a series of higher frequency oscillations (1/f on the order of 103 years). These data confirm the observation that maximal carbonate preservation tends to occur during the later half of glacial stages as shown previously in many Indian and Pacific deep sea core studies.

Global climate changes and natural disasters have happened frequently around the world. It has become a consensus that we should actively develop renewable energy resources and reduce the use of non-renewable energy resources of the Earth. Solar energy has no pollution and does not restrict to regions. Besides, power generated by solar energy reaches the peak in summer which becomes the best solution to ease off the high demand on electricity in summer. However at present, most photovoltaic solar panels are installed on the roofs. The power so generated can only meet one-floor’s electricity demand. Therefore, in order to increase the efficiency of the power generation, the present work took into account the exterior surfaces of buildings, and tried to find the optimum installation position of photovoltaic solar panels for buildings. In this study, we used the solar radiation data of the last decade from the Central Weather Bureau of Taiwan to construct a solar radiation calculation model and a shadow algorithm for the Zhongzheng District in Taipei city, Taiwan. The optimum orientation and height for installing photovoltaic solar panels were calculated. The research results which took a sample building for an example showed that the radiation received by vertical surfaces was reduced because of shadow effect. Besides, the total radiation received by vertical surfaces is more than that received by horizontal surface. The corresponding installation area and irradiation were also computed to provide a reference for the public and the government.

High-resolution records of planktic foraminifer sea-surface temperature (SST) and biogenic sediment components of carbonate and total organic carbon (TOC) concentrations were determined in an IMAGES giant piston core spanning ∼the last 500 000 years, taken near the western slope of Palawan Island in the southeastern South China Sea (SCS). The records provide information of paleoceanographic and paleoclimatological variations linked to East Asian monsoon systems in the SCS, the largest marginal sea of the western Pacific. Constrained by planktic foraminifer (Globigerinoides ruber) oxygen isotope stratigraphies, the records show a lowering of faunal SST by ∼3°C during glacial stages, indicating significant cooling in the glacial western Pacific climate. In general, they show low-frequency patterns with high SSTs, high carbonate content, and low TOC content during interglacial periods, and exhibit low SSTs, low carbonate content, and high TOC content during glacial periods. The carbonate content variations indicate that the sediment composition is mostly controlled by terrigenous inputs, which are associated with sea-level fluctuations in the SCS during past glacial-interglacial stages. The low SST and high TOC content indicate cooling and high productivity conditions in the surface oceans of the SCS, which also reflect a condition of intensified winter monsoon winds associated with glacial boundary conditions. Some rapid, high-frequency oscillations of the SST and TOC found in the records are coincident with intervals of intensified winter or summer monsoons from the Arabian Sea, implying that the Asian monsoon systems had wider regional effects than previously assumed. Time-series analyses reveal that variations in the SST, carbonate and TOC contents of this record contain statistically significant concentrations of variance at orbital frequency bands, namely 100 kyr-1, 41 kyr-1, and 23 kyr-1, suggesting that both ice volume and orbital solar insolation changes are potential mechanisms for the SCS monsoon variations. © 2003 Elsevier Science B.V. All rights reserved.

The collapse of some pre-historical and historical cultures, including Chinese dynasties were presumably linked to widespread droughts, on the basis of synchronicities of societal crises and proxy-based climate events. Here, we present a comparison of ancient inscriptions in Dayu Cave from Qinling Mountains, central China, which described accurate times and detailed impacts of seven drought events during the period of 1520-1920 CE, with high-resolution speleothem records from the same cave. The comparable results provide unique and robust tests on relationships among speleothem δ18 O changes, drought events, and societal unrest. With direct historical evidences, our results suggest that droughts and even modest events interrupting otherwise wet intervals can cause serioussocial crises. Modeling results of speleothem δ18O series suggest that future precipitation in central China may be below the average of the past 500 years. As Qinling Mountain is the main recharge area of two large water transfer projects and habitats of many endangered species, it is imperative to explore an adaptive strategy for the decline in precipitation and/or drought events.

An ice nucleation parameterization based on classical nucleation theory, with aerosol-specific parameters derived from experiments, has been implemented into a global climate model-the Community Atmosphere Model (CAM)-Oslo. The parameterization treats immersion, contact, and deposition nucleation by mineral dust, soot, bacteria, fungal spores, and pollen in mixed-phase clouds at temperatures between 0° and -38°C. Immersion freezing is considered for insoluble particles that are activated to cloud droplets, and deposition and contact nucleation are only allowed for uncoated, unactivated aerosols. Immersion freezing by mineral dust is found to be the dominant ice formation process, followed by immersion and contact freezing by soot. The simulated biological aerosol contribution to global atmospheric ice formation is marginal, even with high estimates of their ice nucleation activity, because the number concentration of ice nucleation active biological particles in the atmosphere is low compared to other ice nucleating aerosols. Because of the dominance of mineral dust, the simulated ice nuclei concentrations at temperatures below -20°C are found to correlate with coarse-mode aerosol particle concentrations. The ice nuclei (IN) concentrations in the model agree well overall with in situ continuous flow diffusion chamber measurements. At individual locations, the model exhibits a stronger temperature dependence on IN concentrations than what is observed. The simulated IN composition (77% mineral dust, 23% soot, and 10-5% biological particles) lies in the range of observed ice nuclei and ice crystal residue compositions. © 2010 American Meteorological Society.

How diversity influences the stability of a community function is a major question in ecology. However, only limited empirical investigations of the diversity-stability relationship in soil microbial communities have been undertaken, despite the fundamental role of microbial communities in driving carbon and nutrient cycling in terrestrial ecosystems. In this study, we conducted a microcosm experiment to investigate the relationship between microbial diversity and stability of soil decomposition activities against changes in decomposition substrate quality by manipulating microbial community using selective biocides. We found that soil respiration rates and degradation enzyme activities by a coexisting fungal and bacterial community (a taxonomically diverse community) are more stable against changes in substrate quality (plant leaf materials) than those of a fungi-dominated or a bacteria-dominated community (less diverse community). Flexible changes in the microbial community composition and/or physiological state in the coexisting community against changes in substrate quality, as inferred by the soil lipid profile, may be the mechanism underlying this positive diversity-stability relationship. Our experiment demonstrated that the previously found positive diversity-stability relationship could also be valid in the soil microbial community. Our results also imply that the functional/taxonomic diversity and community ecology of soil microbes should be incorporated into the context of climate-ecosystem feedbacks. Changes in substrate quality, which could be induced by climate change, have impacts on decomposition process and carbon dioxide emission from soils, but such impacts may be attenuated by the functional diversity of soil microbial communities. © 2013 Ushio et al.

Climate-driven changes in land water storage and their contributions to sea level rise have been absent from Intergovernmental Panel on Climate Change sea level budgets owing to observational challenges. Recent advances in satellite measurement of time-variable gravity combined with reconciled global glacier loss estimates enable a disaggregation of continental land mass changes and a quantification of this term. We found that between 2002 and 2014, climate variability resulted in an additional 3200 ± 900 gigatons of water being stored on land. This gain partially offset water losses from ice sheets, glaciers, and groundwater pumping, slowing the rate of sea level rise by 0.71 ± 0.20 millimeters per year. These findings highlight the importance of climate-driven changes in hydrology when assigning attribution to decadal changes in sea level. © 2016, American Association for the Advancement of Science. All rights reserved.

Cold, nutrient- and CO2-rich waters upwelling in the eastern equatorial Pacific (EEP) give rise to the Pacific cold tongue. Quasi-periodic subsidence of the thermocline and attenuation in wind strength expressed by El Niño conditions decrease upwelling rates, increase surface-water temperatures in the EEP, and lead to changes in regional climates both near and far from the equatorial Pacific. EEP surface waters have elevated CO2 concentrations during neutral (upwelling) or La Niña (strong upwelling) conditions. In contrast, approximate air–sea CO2 equilibrium characterizes El Niño events. One hypothesis proposes that changes in physical oceanography led to the establishment of a deep tropical thermocline and expanded mixed-layer prior to 3 million years ago. These effects are argued to have substantially reduced deep-water upwelling rates in the EEP and promoted a “permanent El Niño-like” climate state. For this study, we test this supposition by reconstructing EEP “excess CO2” and upwelling history for the past 6.5 million years using the alkenone-pCO2 methodology. Contrary to previous assertions, our results indicate that average temporal conditions in the EEP over the past ∼6.5 million years were characterized by substantial CO2 disequilibrium and high nutrient delivery to surface waters — characteristics that imply strong upwelling of deep waters. Upwelling appears most vigorous between ∼6.5 to 4.5 million years ago coinciding with high accumulation rates of biogenic material during the late Miocene – early Pliocene “biogenic bloom”. © 2017 Elsevier B.V.

Widely distributed groups of living animals, such as the predominantly marine fish family Sciaenidae, have always attracted the attention of biogeographers to document the origins and patterns of diversification in time and space. In this study, the historical biogeography of the global Sciaenidae is reconstructed within a molecular phylogenetic framework to investigate their origin and to test the hypotheses explaining the present-day biogeographic patterns. Our data matrix comprises six mitochondrial and nuclear genes in 93 globally sampled sciaenid species from 52 genera. Within the inferred phylogenetic tree of the Sciaenidae, we identify 15 main and well-supported lineages; some of which have not been recognized previously. Reconstruction of habitat preferences shows repeated habitat transitions between marine and euryhaline environments. This implies that sciaenids can easily adapt to some variations in salinity, possibly as the consequence of their nearshore habitats and migratory life history. Conversely, complete marine/euryhaline to freshwater transitions occurred only three times, in South America, North America and South Asia. Ancestral range reconstruction analysis concomitant with fossil evidence indicates that sciaenids first originated and diversified in the tropical America during the Oligocene to Early Miocene before undergoing two range expansions, to Eastern Atlantic and to the Indo-West Pacific where a maximum species richness is observed. The uncommon biogeographic pattern identified is discussed in relation to current knowledge on origin of gradients of marine biodiversity toward the center of origin hypothesis in the Indo-West Pacific. © 2015 Elsevier Inc.

In order to study how the Holocene Central Asian climate is coupled to the global climate system, a 4.24 m long lake core from western Inner Mongolia in China was studied using a multiproxy approach. Sedimentology and geochemical parameters such as gypsum and dolomite content, presence of lakeshore sand changing to aeolian sand, and changes in paleomagnetic properties bear witness to a trend toward a generally drier climate over the late Holocene. Aridification is linked to the southward retreat of the northern boundary of the Asian summer monsoon, leaving central Asia under the influence of the westerly belt. The weakening of the Asian summer monsoon in turn was caused by an orbitally driven decrease in summer insolation. The weakening summer insolation also likely increased the intensity of the Siberian High pressure system, further promoting aridification of central Asia. On a shorter time scale, the multiproxy record shows the climate to have been relatively dry during the Medieval Warm Period (AD 800-1100) with the ensuing humid environment at the end of this period gradually turning to become extremely dry (AD 1100-1550) at the Little Ice Age Maximum. Switches in the North Atlantic Oscillation caused these changes through a teleconnection in the form of westerlies. These westerlies provided most of central Asia's moisture after the retreat of the Asian summer monsoon. The central Asian climate therefore corresponds closely with late Holocene European climate changes. © 2010 Elsevier Ltd and INQUA.

δ13C of total organic carbon (TOC) and pollen grain, TOC, C/N ratio, and δ15N of total organic nitrogen (TON) in a 2.57-m long core from Hoton-Nur Lake in Mongolian Altai have been measured for reconstruction of the Holocene climates. The δ13C values of TOC and pollen carbon have similar average values but different ranges. Pollen δ13C has negative correlation with %AP (arboreal taxa pollen) and positive correlation with %NAP (herbaceous pollen and spores) that are connected with conditions of humidity in the area. Taiga-biome has lighter δ13C than steppe-biome. Hence, pollen δ13C composition is more sensitive to changes of humidity in the analogous spectra than palynotaxonomical structure and δ13C of TOC. Based on our results, the Holocene climates in Mongolian Altai are: (1) dry conditions prior to 11.5kyr BP; (2) wet conditions between 11.5 and 6.0kyr BP; (3) a relatively dry/cool episode during 6-4kyr BP; (4) stable cool and semiarid conditions with moderately effective moisture during the past 4000years. Two abrupt climatic changes occurred at ∼7.45kyr BP and ∼11.5kyr BP might be related to glacial activities. The Holocene climatic trend in Mongolian Altai which is controlled by the Westerlies is similar to the trend of monsoonal climate shown by the Chinese speleothem records as well as the lake/sand dune evidence in the deserts of NW China. The contact of the two climatic systems and shift of the monsoonal boundary during the past need to be further studied. © 2012 Elsevier Ltd.

A procedure to determine soil moisture threshold (θ*), cover coefficient (kc), and parameters of soil moisture stress function (ks) is proposed in this study. These coefficients can be further applied to estimate daily actual evapotranspiration in a hydrological model. Two soil moisture stress functions are used to describe ks. One of the functions is proposed by this study, which assumes moisture stress is inversely proportional to matric potential described by van Genuchten retention curve. The procedure is applied to identify the coefficients for three kinds of reference potential evapotranspiration based on soil moisture monitoring. Soil moisture was measured by Watermark soil moisture sensors. These sensors were tested in a laboratory to establish the relationship between soil moisture and recorded tensor. Then, these sensors were installed in an experimental forest watershed. The verification study shows that the calibrated coefficients can provide reasonable estimate of actual evapotranspiration. The R2 = 0. 85 for using the Penman-Montieth equation for tall maize along with kc = 1. 81 can be obtained for the validation period with soil moisture stress. Besides, the results also indicate the proposed soil moisture stress function can have better performance on estimating daily actual evapotranspiration at early stage of a dry period. The proposed procedure and soil moisture stress functions can be successfully applied to estimate daily evapotranspiration when soil moisture is known. However, their performance in a hydrological model requires further study, since a hydrological model can only provide estimated soil moisture. © 2012 Springer-Verlag.

The Integrated Ocean Drilling Program (IODP) Expedition 310 recovered drill cores from the drowned reefs around the island of Tahiti (17°40′S, 149°30′W), many of which contained samples of massive corals from the genus Porites. Herein we report on one well-preserved fossil coral sample: a 13.6 cm long Porites sp. dated by uranium series techniques at 9523 ± 33 years. Monthly δ18O and Sr/Ca determinations reveal nine clear and robust annual cycles. Coral δ18O and Sr/Ca determinations estimate a mean temperature of ∼24.3°C (∼3.2°C colder than modern) for Tahiti at 9.5 ka; however, this estimate is viewed with caution since potential sources of cold bias in coral geochemistry remain to be resolved. The interannual variability in coral δ18O is similar between the 9.5 ka coral record and a modern record from nearby Moorea. The seasonal cycle in coral Sr/Ca is approximately the same or greater in the 9.5 ka coral record than in modern coral records from Tahiti. Paired analysis of coral δ18O and Sr/Ca indicates cold/wet (warm/dry) interannual anomalies, opposite from those observed in the modern instrumental record. © Copyright 2010 by the American Geophysical Union.

Tropical cyclones are one of the most serious natural disasters in northwestern Pacific Ocean. In general, an average of three to four typhoons invades the vicinity of Taiwan annually, which brings heavy rainfalls and strong winds resulting in disasters including flooding, mudflows, and landslides, leading to severe damage to economies and casualties. Studies show that different tracks of typhoon can cause distinct spatio-temporal patterns of rainfall events at different regions of Taiwan. As a result, understanding the trajectories of tropical cyclones and their relationship to climatic variables at global scale is crucial for hydrological modeling and disaster migration in Taiwan, especially under the conditions of climate change. This study applied a probabilistic curve clustering technique, which is based on a regression mixture model, to classify the best tracks of typhoons across the area within 6° around Taiwan during the period of 1951–2009. For the purposes of modeling and forecasting the typhoon trajectories, the track cluster is performed separately in different seasons due to their distinct driving forces to typhoon movements. A generalized linear model (GLM) is used to characterize the relationship between the identified typhoon tracks and the dominant climate features derived from NCEP reanalysis data. Results showed the six major typhoon tracks in the vicinity of Taiwan for different seasons respectively. The result of GLM cross validation showed that the frequency of typhoon tracks passing cross Taiwan in summer can significantly depend upon with two empirical orthogonal functions (EOFs) of sea level pressure, and the third EOF of sea surface temperature. © 2014, Springer-Verlag Berlin Heidelberg.

Dengue Fever (DF) has been identified by the World Health organization (WHO) as one of the most serious vector-borne infectious diseases in tropical and sub-tropical areas. During 2007, in particular, there were over 2,000 DF cases in Taiwan, which was the highest number of cases in the recorded history of Taiwan epidemics. Most DF studies have focused mainly on temporal DF patterns and its close association with climatic covariates, whereas they have understated spatial DF patterns (spatial dependence and clustering) and composite space-time effects. The present study proposes a spatio-temporal DF prediction approach based on stochastic Bayesian Maximum Entropy (BME) analysis. Core and site-specific knowledge bases are considered, including climate and health datasets under conditions of uncertainty, space-time dependence functions, and a Poisson regression model of climatic variables contributing to DF occurrences in southern Taiwan during 2007. The results show that the DF outbreaks in the study area are highly influenced by climatic conditions. Furthermore, the analysis can provide the required "one-week-ahead" outbreak warnings based on spatio-temporal predictions of DF distributions. Therefore, the proposed approach can provide the Taiwan Disease Control Agency with a valuable tool to timely identify, control, and even efficiently prevent DF spreading across space-time. © 2010 Springer-Verlag.

The WRF Model is used to simulate 52 tropical cyclones (TCs) that formed in the western North Pacific during 2008-09 to study the influence of the low-frequency mode of environmental vorticity on TC formation [Vmax ~ 25 kt (~13ms-1)]. All simulations, using the same model setting, are repeated at four distinct initial times and with two different initial datasets. These TCs are classified into two groups based on the environmental 850-hPa low-frequency vorticity (using a 10-day low-pass filter) during the period 24-48 h prior to TC formation. Results show that theWRFModel is more capable of simulating the TC formation process, but with larger track errors for TCs formed in an environment with higher low-frequency vorticity (HTC). In contrast, the model is less capable of simulating the TC formation process for TCs formed in an environment with lower low-frequency vorticity (LTC), but with smaller track errors. Fourteen selected TCs are further simulated to examine the sensitivity of previous results to different cumulus parameterization schemes. Results show that the capability of theWRFModel to simulateHTCformation is not sensitive to the choice of cumulus scheme. However, for an LTC, the simulated convection pattern is very sensitive to the cumulus scheme used; therefore, model simulation capability for LTC depends on the cumulus scheme used. Results of this study reveal that the convection process is not a dominant factor in HTC formation, but is very important for LTC formation. © 2017 American Meteorological Society.

A super Asian dust (SAD) storm that originated from North China has affected East Asia since 20 March 2010. The tempo-spatial and size distributions of aerosol Al, a tracer of wind-blown dust, were measured on a regional aerosol network in March 2010. Two dust events were recorded: the SAD and a relatively moderate AD event. The SAD clouds raised Al concentrations to ~50 μg/m 3 on 21 and 22 March over the East China Sea (ECS) and occupied there for ~5 days. The SAD plume also stretched toward the South China Sea (SCS) on 21 March however, it caused a maximum Al concentration of ~8.5 μg/m 3 only, much lower than that observed in the ECS. In comparison, a weaker dust plume on 16 March caused Al maximum of ~4 μg/m3 over the ECS, and comparably, ~3 μg/m3 in the SCS. Dry dust deposition was measured during the peak phase of the SAD at 178 mg/m2/d, which corresponded to dry deposition velocities of 0.2-0.6 cm/s only, much lower than the commonly adopted one (1-2 cm/s). The corresponding increase in dust deposition by the SAD was up to a factor of ~12, which was, however, considerably disproportionate to the increase in dust concentration (i.e., the factor of over 100). In certain cases, synoptic atmospheric conditions appear to be more important in regulating dust contribution to the SCS than the strength of AD storms. Key Points A super Asian dust observed on a regional aerosol network over the ocean Increase in dust deposition is disproportionate to that in dust concentration Synoptic weather conditions play a critical role in AD transport to the SCS ©2013. American Geophysical Union. All Rights Reserved.