ENSO Climate Research Articles

The evolution and relationship of the Yellow Sea warm current and the Yellow Sea Cold Water Mass since the Mid-Holocene and possible ENSO influences

The Yellow Sea Warm Current (YSWC) and Yellow Sea Cold Water Mass (YSCWM) are crucial components of Yellow Sea oceanic dynamics. Investigating their historical relationships since the mid-Holocene, as demonstrated by modern observations, is highly important. We reconstructed their evolution using 37 surface sediment samples and core Z1 from the Yellow Sea. Basic end-member analysis of core sediment grain sizes revealed that end-member two had a dominant peak at 12 μm, indicating the evolution of the YSWC. The analysis of the structure of benthic foraminiferal communities in surface sediments indicated that the combination of Ammonia ketienziensis, Hanzawaia nipponica, and Astrononion italicum serves as a reliable indicator of the evolution of the YSCWM. By integrating sedimentological and micro-palaeontological evidence with published organic geochemical findings, we elucidated high-resolution evolutionary records of the YSWC and YSCWM since the mid-Holocene. Our findings indicate that the YSWC underwent rapid intensification with significant fluctuations during ∼6.0–3.9 ka. It then decreased to modern levels between ∼3.9 ka and ∼1.9 ka, remaining relatively stable during ∼1.9–0.0 ka, with enhancements noted at ∼1.4 ka and ∼0.3 ka. The YSCWM evolved synchronously with the YSWC after ∼6.0 ka, weakened and then strengthened during ∼6.0–1.9 ka, and maintained relative stability during ∼1.9–0.0 ka, with decreases observed at ∼1.4 ka and ∼0.3 ka. The YSWC and YSCWM exhibited opposite changes, similar to modern oceanographic patterns, except for synchronous variations during ∼4.0–3.9 ka, when the YSCWM was formally established. The decoupling of the YSCWM and the YSWC during ∼4.0–3.9 ka and the significant enhancements of the YSCWM at ∼2.5 ka and ∼2.0 ka when the YSWC slightly weakened are associated with the substantial influence of the ENSO climate phenomena on the coastal regions of East Asia from ∼4.0 ka to ∼1.9 ka. We propose that the YSCWM is more sensitive to ENSO, potentially making it more suitable for reconstructing the palaeoceanography and palaeoclimatology of the Yellow Sea.

Characterizing the regional XCO2 variability and its association with ENSO over India inferred from GOSAT and OCO-2 satellite observations

India is primarily concerned with comprehending regional carbon source-sink response in the context of changes in atmospheric CO2 concentrations or anthropogenic emissions. Recent advancements in high-resolution satellite's fine-scale XCO2 measurements provide an opportunity to understand unprecedented details of source-sink activity on a regional scale. In this study, we investigated the long-term variations of XCO2 concentration and growth rates as well as its covarying relationship with ENSO and regional climate parameters (temperature, precipitation, soil moisture, and NDVI) over India from 2010 to 2021 using GOSAT and OCO-2 retrievals. The results show since the launch of OCO-2 in 2014, the number of monthly high-quality XCO2 soundings over India has grown nearly 100-fold compared to GOSAT, launched in 2009. Also, the discrepancy in XCO2 increase of 2.54(2.43) ppm/yr was observed in GOSAT (OCO-2) retrieval during an overlapping measurement period (2015–2021). Additionally, wavelet analysis indicated that the OCO-2 retrieval is able to capture a better frequency of local-scale XCO2 variability compared to GOSAT, owing to its high-resolution cloud-free XCO2 soundings, providing more well-defined regional-scale source-sink features. Furthermore, dominant spatial pattern of XCO2 variability observed over south and southeast of India in both satellites, with XCO2 semi-annual and annual variability more distinctly present in OCO-2 compared to GOSAT. A cross-correlation analysis suggested GOSAT XCO2 growth rate positively correlates with ENSO in different homogeneous monsoon regions of India, with ENSO leading the GOSAT XCO2 growth rate in all homogeneous regions by 3–9 months. The South Peninsular region sensitive to ENSO changes, especially during 2015–2016 ENSO event, where a decrease in CO2 uptake was observed is closely linked with precipitation, soil moisture, and temperature anomalies. However, regional climate parameters show a low correlation with XCO2 growth since CO2 is a long-lived well-mixed gas primarily having an imprint of large-scale transport in column CO2.

Assessment of Drought Disasters (EDI) Based on ENSO and NOAA Climate Data Using ANN in Bondowoso Regency

Assessment of Drought Disasters (EDI) Based on ENSO and NOAA Climate Data Using ANN in Bondowoso Regency

Influence of Winter Subsurface on the Following Summer Variability in Northern California Current System

AbstractTemperature variations in the North and tropical Pacific contribute to the predictability of temperatures along the 26.4σ isopycnal layer off the Northern California Current System (N‐CCS). Monthly temperature variations at this depth in the N‐CCS are related to a linear combination of factors, including North Pacific spice anomalies, and the PDO and ENSO climate indices. However, the mechanisms for seasonal predictability of subsurface temperatures, are not well explored. While wind and buoyancy driven deep winter mixing influence subsurface temperatures during the following summer in the deep basin of the North Pacific, a coupled atmosphere‐ocean reanalysis (the CFSR) reveals that winter prior surface temperatures explain only 25% of the summer subsurface temperatures in the N‐CCS. A heat budget of the intermediate layer between a temporally varying mixed layer and the 26.4σ level is diagnosed here to explore the possible role of oceanic advection in explaining the remaining variance. Warmer waters from the south near the coast drive temperature changes in ENSO‐neutral winters, thereby preconditioning temperatures for the following summer. During ENSO winters, isopycnal variations associated with propagating coastal kelvin waves and other sources of heaving, along with anomalous alongshore currents, drive convergence/divergence of the advective fluxes, thereby reducing the local memory of the winter subsurface temperatures. Variations in winter advection could account for almost 36% of the summer subsurface temperature variability in the N‐CCS; this exceeds the portion explained by the heat fluxes associated with deep winter mixing.

A Statistical Intraseasonal Prediction Model of Extended Boreal Summer Western North Pacific Tropical Cyclone Genesis

Abstract An L2 regularized logistic regression model is developed in this study to predict weekly tropical cyclone (TC) genesis over the western North Pacific (WNP) Ocean and subregions of the WNP including the South China Sea (SCS), the western WNP (WWNP), and the eastern WNP (EWNP). The potential predictors for the TC genesis model include a time-varying TC genesis climatology, the Madden–Julian oscillation (MJO), the quasi-biweekly oscillation (QBWO), and ENSO. The relative importance of the predictors in a constructed L2 regression model is justified by a forward stepwise selection procedure for each region from a 0-week to a 7-week lead. Cross-validated hindcasts are then generated for the corresponding prediction schemes out to a 7-week lead. The TC genesis climatology generally improves the regional model skill, and the importance of intraseasonal oscillations and ENSO is regionally dependent. Over the WNP, there is increased model skill over the time-varying climatology in predicting weekly TC genesis out to a 4-week lead by including the MJO and QBWO, whereas ENSO has a limited impact. On a regional scale, ENSO and then either the MJO or QBWO are the two most important predictors over the EWNP and WWNP after the TC genesis climatology. The MJO is found to be the most important predictor over the SCS. The logistic regression model is shown to have comparable reliability and forecast skill scores to the ECMWF dynamical model on intraseasonal time scales. Significance Statement Skillful forecasts of tropical cyclone activity on time scales from short-range to seasonal are now issued operationally. Although there has been great progress in the understanding of physical mechanisms driving tropical cyclone (TC) activity, intraseasonal prediction of TCs remains a significant scientific challenge. This study develops a statistically based intraseasonal model to predict weekly TC genesis over the western North Pacific Ocean basin. The intraseasonal prediction model developed here for TC genesis over the western North Pacific basin shows skill extending out to four weeks. We discuss the regional dependence of the model skill on ENSO and other subseasonal climate oscillations. This approach provides skillful intraseasonal forecasting of TCs over the western North Pacific basin.

Revisiting the strong and weak ENSO teleconnection impacts using a high-resolution atmospheric model

To evaluate the performance of a high-resolution atmospheric model (HiRAM) and to improve our understanding of the climatic impacts of ENSO forcing and associated teleconnections, we analyzed AMIP-style HiRAM simulations conducted effectively at 25 km grid spacing. To better assess HiRAM response to ENSO climate variability; we categorized it into strong and weak El Niño/La Niña episodes. The HiRAM model reproduced the impacts of strong ENSO over global scale very well, however, it underestimated ENSO teleconnection patterns and associated changes over regional scale (e.g., MENA and South Asia), especially following weak ENSO that could be attributed to model weak response to circulation changes such as Pacific North American (PNA) and North Atlantic Oscillation (NAO). Moreover, our results emphasize that ENSO impacts are relatively stronger over the Inter-Tropical Convergence Zone (ITCZ) compared to extra-tropics and high-latitude regions. The positive phase of ENSO causes weakening in rainfall over the African tropical rain-belt, parts of South and Southeast Asia. Both the reanalysis and HiRAM results reveal that ENSO-induced negative (positive) NAO-like response and associated changes over Southern Europe and North Africa vary significantly following the increased intensity of El Niño (La Niña). We further found that the ENSO magnitude significantly impacts Hadley and Walker circulations. The El Niño phase of ENSO overall strengthens the Hadley Cell, and the reverse is true for the La Niña phase. This ENSO-induced strengthening and weakening of Hadley Cell induce significant impact over South Asian and African convective regions through modification of the ITCZ circulation system.

Regional Agroclimate Characteristic and Its Multiple Teleconnections: A Case Study in the Jianghan Plain (JHP) Region

Agricultural production depends on local agroclimatic conditions to a great extent, affected by ENSO and other ocean-atmospheric climate modes. This paper analyzed the spatio-temporal distributions of climate elements in the Jianghan Plain (JHP), Central China, and explored the impacts from teleconnection patterns, aimed at providing references for dealing with climate change and guiding agricultural activities. Both linear and multifactorial regression models were constructed based on the frequentist quantile regression and Bayesian quantile regression method, with the daily meteorological data sets of 17 national stations in the plain and teleconnection climate characteristic indices. The results showed that precipitation in JHP had stronger spatial variability than evapotranspiration. El Niño probably induced less precipitation in summer while the weakening Arctic Oscillation might lead to more summertime precipitation. The Nash-Sutcliffe efficiency (NSE) of the multifactorial and linear regression model at the median level were 0.42–0.56 and 0.12–0.18, respectively. The mean relative error (MRE) ranged −2.95–−0.26% and −7.83–0.94%, respectively, indicating the much better fitting accuracy of the multiple climatic factors model. Meanwhile it confirmed that the agricultural climate in JHP was under the influence from multiple teleconnection patterns.

Variation in Seed Harvest Potential of Carapa guianensis Aublet in the Brazilian Amazon: A Multi-Year, Multi-Region Study of Determinants of Mast Seeding and Seed Quantity

This work augments research on masting for the economically important tropical tree Carapa guianensis Aublet, specifically on whether determinants of mast years vary regionally, spatially, and due to longer term ENSO climate patterns. Longer term measurements (an 11-year period in Acre and Roraima; 4 years and 8 months in Amapá) from three regions of the Brazilian Amazon allowed for the analysis of whether climate cues were regionally consistent for this species. We used generalized linear mixed models, to determine which factors were significant in predicting whether trees would produce in a given year and to model the seed production quantity. We found a positive effect of increasing the diameter at breast height (dbh) on the quantity and likelihood of seed production. Our results also suggested that ecosystems and climate cues may jointly affect seed production. In flooded forests, increases in dry season rainfall had a negative impact on the likelihood of seed production whilst none of the precipitation variables investigated influenced the quantity of seeds produced. In drier terra firme forests in Acre with extended dry seasons, increases in dry season precipitation had significant and positive impacts on both the likelihood and the quantity of seed production. Our results illustrate the importance of considering plant habitat and climate to better understand individual and regional differences in seed production and their responses to inter-annual climate variation.

Teleconnection Between ENSO and Wind-Wave Climate Under the Influence of Monsoon in the Bay of Bengal Region

Wind-wave parameters like the significant wave height (SWH)impacts considerably deep ocean and maritime activities and lives of all those dwelling near the coast.Prediction of such a parameter has immense utility during extreme conditions. Teleconnection features are explored between the most widely studied climate mode, the El Niño-Southern Oscillation or ENSO and the SWHparameter in the Bay of Bengal (BB) region under the influence of monsoon in this study.In two separate experiments the SWH data of the BB region for the period 1958-2001 and the period 2006-2016 is subjected to empirical orthogonal function analysis to split the data into spatial and temporal parts.The temporal variations are of annual periodicity for both the data sets. On analysis teleconnection feature of lower (higher) SWH during El Niño (La Niña) episodes is observed in the BB region. Significant correlationis observed between SWH and the ENSO indices during the summer monsoon months.The continuous wavelet power spectrum is generated using the first principal component (PC1) extracted above. It exhibits significant regions in the 0.5-1 year band resembling the monsoon variability in the BB region. To determine how SWH is related to the ENSO indices wavelet coherence is applied for the BB region.The higher coherency regions are found in the 0.5-1 year band which maybe related to the monsoon oscillation having similar periodicity. Thus the SWH and ENSO relationship in the BB region is influenced by the monsoon significantly.

Rainfall variability in the Brazilian northeast biomes and their interactions with meteorological systems and ENSO via CHELSA product

ABSTRACTBrazilian biomes are home to a significant portion of the world’s biodiversity, with a total of 14% of existing species and still concentrate 20% of the world’s water resources. However, changes in biomes have a direct impact on rainfall patterns and water recycling. Based on this, the objective was to evaluate the variability of rainfall in the four existing biomes in the Northeast Brazil (NEB) and their interaction with the ENSO climate variability mode and regional scale meteorological systems via CHELSA product. For this, monthly rainfall data were used from 1979 to 2013, with a spatial resolution of 1 km × 1 km of the CHELSA product, and seasonal and annual rainfall patterns were extracted via boxplot. It was found that the rainy season in the Amazon, Caatinga and Cerrado biomes occurred between January and April, with varying intensities, except for the Atlantic Forest. Such seasonality patterns are associated with the NEB meteorological systems, with emphasis on ITCZ (all Biomes), UTCV (Amazon, Caatinga and Cerrado), Frontal Systems (extreme south of Caatinga, Cerrado and Atlantic Forest) and EWD/TWD in the (Atlantic Forest). In the inter-annual scale, the remarkable influence of ENSO was verified, mainly in the years 1983, 1985, 1989, 1993, 1998, 2009 and 2012. It is noteworthy that 1985 was the wettest year of the period, with a surplus in all biomes, while the driest year differs between the Amazon (1983), Atlantic Forest and Caatinga (1993) and Cerrado (2012) biomes. The study via orbital product in NEB showed that anthropogenic processes and natural variability interfere with the forms of rain interception in the biomes and hence in rainfall patterns and water recycling in NEB.

Equatorward western boundary transport from the South Pacific: Glider observations, dynamics and consequences

The Solomon Sea carries the equatorward western boundary current of the South Pacific, a principal element of subtropical-equatorial communication. Eighty-seven glider transects across the mouth of the Sea over nine years describe the velocity structure and variability of this system. The time series spans two El Niños and two La Niñas, which produced large transport anomalies, up to 50% of the mean. While transport increased during El Niños and decreased during La Niñas, their signatures were inconsistent among the events. Separated glider tracks show the merging of two inflows, one from the tropics east of the Solomon Island chain, the other entering as a western boundary current generated by winds over the full subtropical gyre. A model of linear wind-driven dynamics, including western boundary currents, had skill in describing the variability of the two inflows, identifying the distinct wind forcing driving each. The model suggests that both the mean and low-frequency variability of flow entering the Solomon Sea are driven remotely by wind over the South Pacific, acting through long Rossby waves. The ultimate significance of in situ observations in this small sea will be to describe its role in subtropical-tropical heat exchange that is crucial to ENSO and longer-timescale climate variations along the equator. We take an initial step here, suggesting that temperature advection through the Solomon Sea is a first-order contribution to interannual temperature changes of the equatorial strip as a whole.

엘니뇨-남방진동과 한반도 겨울철 기후변동성의 그랜저 인과관계 검정

엘니뇨-남방진동과 한반도 겨울철 기후변동성의 그랜저 인과관계 검정

Evidence of solar insolation and internal forcing of sea surface temperature changes in the eastern tropical Indian Ocean during the Holocene

The forcing and mechanisms governing sea surface temperature (SST) variations in the Indo-Pacific Warm Pool (IPWP) are complex. Insight into the full spectrum of IPWP climate dynamics, however, is limited by the spatial and temporal coverage of the climate data. In particular, the relationships among the changes in the SSTs, the precipitation patterns mainly associated with rainfalls from Asian Monsoons (AM), and the Indian Ocean Dipole (IOD) are poorly understood. To help us further assess the climate linkages, we have reconstructed a more spatial SST pattern during the Holocene by using multiple SST proxies (alkenone unsaturation index U37k' and Mg/Ca of planktic foraminifer) in the Eastern Tropical Indian Ocean (ETIO), the western margin of the IPWP based on three sedimentary cores from NW offshore of Sumatra, and offshore of Sumatra and Java (BS24, SO139-74KL, and SO184-100430). Stable hydrogen and carbon isotope records of terrestrial plant waxes from a nearby marine sediment core SO189-144KL and geochemical tracers measured from the coral reefs within the Mentawai Islands in the ETIO are used here as AM driven precipitation and IOD records in our data synthesis. Not surprisingly, our synthesis suggests that insolation plays a major role that has been responsible for the increased SSTs in ETIO since the early Holocene, while other mechanisms remain effective in determining the timing of our reconstructed SST variations. In particular, our SST pattern shares less similarity with that of coral Sr/Ca SST and is decoupled from the coral IOD events in the mid-Holocene. We interpret that our reconstructed ETIO SSTs are driven dominantly by the solar forcing, but are also affected by other internal climate mechanisms such as the local shifts in AM-controlled upwelling and precipitation, episodic reductions in the flow of warm western Pacific surface water into the Indian Ocean due to increased precipitation over the Indonesian archipelago, and long-term ENSO or IOD-like climate change.

Were merely storm-landslides driven by the 2015-2016 Niño in the Mendoza River valley?

Since Holocene time, above-mean precipitations recorded during the El Nino warm ENSO phase have been linked to the occurrence of severe debris flows in the arid Central Andes. The 2015–2016 El Nino, for its unusual strength, began driving huge and dangerous landslides in the Central Andes (32°) in the recent South Hemisphere summer. The resulting damages negatively impacted the regional economy. Despite this, causes of these dangerous events were ambiguously reported. For this reason, a multidisciplinary study was carried out in the Mendoza River valley. Firstly, a geomorphological analysis of affected basins was conducted, estimating morphometric parameters of recorded events such as velocity, stream flow, and volume. Atmospheric conditions during such events were analyzed, considering precipitations, snow cover, temperature range, and the elevation of the zero isotherm. Based on our findings, the role of El Nino on the slope instability in the Central Andes is more complex in the climate change scenario. Even though some events were effectively triggered by intense summer rainstorm following expectations, the most dangerous events were caused by the progressive uplifting of the zero isotherm in smaller basins where headwaters are occupied by debris rock glaciers. Our research findings give light to the dynamic coupled system ENSO–climate change–landslides (ECCL) at least in this particular case study of the Mendoza River valley. Landslide activity in this Andean region is driven by wetter conditions linked to the ENSO warm phase, but also to progressive warming since the twentieth century in the region. This fact emphasizes the future impact of the natural hazards on Andean mountain communities.

Extreme Rainfall (R20mm, RX5day) in Yangtze–Huai, China, in June–July 2016: The Role of ENSO and Anthropogenic Climate Change

Extreme Rainfall (R20mm, RX5day) in Yangtze–Huai, China, in June–July 2016: The Role of ENSO and Anthropogenic Climate Change

Complex picture for likelihood of ENSO-driven flood hazard

El Niño and La Niña events, the extremes of ENSO climate variability, influence river flow and flooding at the global scale. Estimates of the historical probability of extreme (high or low) precipitation are used to provide vital information on the likelihood of adverse impacts during extreme ENSO events. However, the nonlinearity between precipitation and flood magnitude motivates the need for estimation of historical probabilities using analysis of hydrological data sets. Here, this analysis is undertaken using the ERA-20CM-R river flow reconstruction for the twentieth century. Our results show that the likelihood of increased or decreased flood hazard during ENSO events is much more complex than is often perceived and reported; probabilities vary greatly across the globe, with large uncertainties inherent in the data and clear differences when comparing the hydrological analysis to precipitation.

Particle‐size evidence of barrier estuary regime as a new proxy for ENSO climate variability

AbstractWe investigate a new proxy for ENSO climate variability based on particle‐size data from long‐term, coastal sediment records preserved in a barrier estuary setting. Corresponding ~4–8 year periodicities identified from Wavelet analysis of particle‐size data from Pescadero Marsh in Central Coast California and rainfall data from San Francisco reflect established ENSO periodicity, as further evidenced in the Multivariate ENSO Index (MEI), and thus confirms an important ENSO control on both precipitation and barrier regime variability. Despite the fact that barrier estuary mean particle size is influenced by coastal erosion, precipitation and streamflow, balanced against barrier morphology and volume, it is encouraging that considerable correspondence can also be observed in the time series of MEI, regional rainfall and site‐based mean particle size over the period 1871–2008. This correspondence is, however, weakened after c.1970 by temporal variation in sedimentation rate and event‐based deposition. These confounding effects are more likely when: (i) accommodation space may be a limiting factor; and (ii) particularly strong El Niños, e.g. 1982/1983 and 1997/1998, deposit discrete >cm‐thick units during winter storms. The efficacy of the sediment record of climate variability appears not to be compromised by location within the back‐barrier setting, but it is limited to those El Niños that lead to barrier breakdown. For wider application of this particle size index of ENSO variability, it is important to establish a well‐resolved chronology and to sample the record at the appropriate interval to characterize deposition at a sub‐annual scale. Further, the sample site must be selected to limit the influence of decreasing accommodation space through time (infilling) and event‐based deposition. It is concluded that particle‐size data from back‐barrier sediment records have proven potential for preserving evidence of sub‐decadal climate variability, allowing researchers to explore temporal and spatial patterns in phenomena such as ENSO. Copyright © 2017 John Wiley & Sons, Ltd.

Hematology hurdles – Infusion of biologics in cynomolgus monkeys

A multi-proxy reconstruction of a sediment core from the Tatos basin in the Mauritian lowlands reveals a dynamic environmental history during the last 8000 years. Under influence of sea level rise, the basin progressed from a wetland to a shallow lake between 8000 and 2500 cal yr BP and it slowly changed back into a wetland after sea level reached its highest position at around 2500 cal yr BP. The groundwater level in the basin was strongly affected by sea level rise and precipitation-forced runoff through the porous volcanic bedrock.Millennial-scale precipitation changes in the Mauritian lowlands were derived from the pollen records of semi-dry forest and palm woodland. Salinity and environmental reconstructions based on diatoms, ostracods, stable isotopes and sediment composition showed numerous decadal and centennial droughts and wet events. Mauritius experienced wet conditions between ∼8000 and ∼6800 cal yr BP, followed by decreasing humidity from 6800 to 6000 cal yr BP. Dry conditions persisted until ∼1200 cal yr BP, after which wetter conditions have prevailed as recorded from Mauritian lowland and upland records. Climate dynamics reflects northern hemisphere monsoon activity and suggest that Mauritian rainfall and the Indian and Asian summer monsoons are linked, as both receive moisture from the southern equatorial Indian Ocean.The anti-phased relationship of climate dynamics between the Mauritian lowlands and western tropical Australia during the middle Holocene is interpreted as a prolonged configuration of a negative mode of the Indian Ocean Dipole (IOD). A negative IOD-like state is supported by decreased Asian summer monsoon rainfall, higher Austral-Indonesian summer monsoon rainfall and lower temperatures in the Kilimanjaro record. Conversely, repeated decadal-scale wet events in the Mauritian lowlands occurring every ∼350 years reflect short positive IOD-like events.The onset of ENSO climate variability followed an anomalously strong negative IOD-like event and shifted teleconnections from the tropical Indian Ocean to the Pacific Ocean. A shift in ENSO activity around ∼2600 cal yr BP signifies the decoupling of ENSO from the Atlantic ITCZ. Subsequently, the influence of ENSO on climate in the western Indian Ocean is indicated by increased storm frequency and drought events after 2660 cal yr BP in Mauritius and reduced monsoon activity in the western and eastern Indian Ocean.

Understanding cold bias: Variable response of skeletal Sr/Ca to seawater pCO2 in acclimated massive Porites corals.

Coral skeletal Sr/Ca is a palaeothermometer commonly used to produce high resolution seasonal sea surface temperature (SST) records and to investigate the amplitude and frequency of ENSO and interdecadal climate events. The proxy relationship is typically calibrated by matching seasonal SST and skeletal Sr/Ca maxima and minima in modern corals. Applying these calibrations to fossil corals assumes that the temperature sensitivity of skeletal Sr/Ca is conserved, despite substantial changes in seawater carbonate chemistry between the modern and glacial ocean. We present Sr/Ca analyses of 3 genotypes of massive Porites spp. corals (the genus most commonly used for palaeoclimate reconstruction), cultured under seawater pCO2 reflecting modern, future (year 2100) and last glacial maximum (LGM) conditions. Skeletal Sr/Ca is indistinguishable between duplicate colonies of the same genotype cultured under the same conditions, but varies significantly in response to seawater pCO2 in two genotypes of Porites lutea, whilst Porites murrayensis is unaffected. Within P. lutea, the response is not systematic: skeletal Sr/Ca increases significantly (by 2–4%) at high seawater pCO2 relative to modern in both genotypes, and also increases significantly (by 4%) at low seawater pCO2 in one genotype. This magnitude of variation equates to errors in reconstructed SST of up to −5 °C.

Ignition Stories: Indigenous Fire Ecology in the Indo-Australian Monsoon Zone

Ignition Stories: Indigenous Fire Ecology in Indo-Australian Monsoon Zone Cynthia Fowler Carolina Academic Press Ritual Studies Monograph Series, Durham, NC, 2013 302 pp. $38.00 paperback Reviewed by Michael R. CoughlanThe use and control of fire is one of defining char- acteristics of being human. Yet, fire remains remark- ably understudied from a social science perspective. As a book-length ethnographic monograph, Cynthia Fowler's Ignition Stories is first of its kind to focus almost entirely on subject of fire and its use by a specific people. Ignition Stories sets out to enlighten us on how fire is intricately tied to primordial concerns of identity, kinship, marriage, gender, exchange, religion, and politics, while at same time contributing to scientific understandings of fire and environmental change (p. 8). Although this may seem like a logical and straightforward path narrative to take, addressing these dual concerns is an ambitious undertaking. It requires narrative to simultaneously focus on cultural importance of fire to a people (the ethnography of fire) and importance of people to fire (the fire ecology). Ignition Stories has trouble delivering on its promise to overlay these foci.Through a compassionate and humanistic narrative, Ignition Stories describes how fire and fire practice are imbricated in social and psychological fabric of people of Sumba, Eastern Indonesia. Fowler draws heavily on anthropological writing styles of Clifford Geertz and Tim Ingold to create a work she herself calls a textual analysis of fire stories and nonfic- tion (p. 8). The author clearly excels at creative and interpretive ethnographic writing. The ethnographic vignettes are well crafted and interesting. The use of fire metaphors in chapter titles and in narrative more generally, are on par with those of Stephen Pyne (1982), though some readers may tire of this rhetorical device.Fowler also represents Ignition Stories as a work of envi- ronmental anthropology, with an objective of illuminat- ing too often ignored perspective. The narrative clearly embraces environmental anthropology's liberal application of ecological (in both term and con- cept) and its claims to policy relevance. Throughout narrative, promise of a policy-relevant indigenous fire is hinted at and outlined as a major contri- bution of book to fire studies. However, analyses lack rigor and resulting portrait of indigenous fire remains vague. This is notably problematic with Fowler's description of Kodi's fire regimes (p. 131 -134) which she outlines for purpose of describing a key mechanism of region's disturbance ecology (p.131). Fowler defines fire regime concept as the frequency, intensity, severity, and/or seasonality of fire together with fuel consumption, fire spread, and size and distribution of burned patches (p.131), yet fails to provide more than a general qualitative summary of monsoon-driven fire seasonality her field site. The reader is left to wonder what percent of a village landscape burns in a given year or season. What are actual sizes and distributions of dif- ferent types of fires she documented? How much land does a single household burn and how frequently do they burn it? If ENSO climate events are significant fire regime, how exactly do Kodi work within and capitalize upon climatic patterns that produce Island's fire-adapted landscapes (p. 144)? These are temporal and spatial parameters that ethnographers can contribute to inform evidence-based fire policy.As an introductory chapter, Chapter 1 reflects holistic viewpoint imparted throughout book. In addition to some basic background information, chapter touches on a wide breadth of theoretical topics including issues of scale, cosmology, kinship, tenets of interpretive anthropology, and emergent properties in systems. …