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A combination of careful harmonic analysis and high-resolution numerical modelling of tides in altimeter data from TOPEX/Poseidon and ERS-2 satellites allows detailed calculation of seasonal and interannual variability of sea level in coastal areas of the north-east Pacific Ocean. These calculations show large changes in sea level in marginal seas during the 1997-8 El Niño and La Niña events, as well as providing information on the origin and life cycle of large anticyclonic eddies, observed to be generated off the west coast of Canada. [ABSTRACT FROM AUTHOR]

Lake surface water temperature (LSWT) is sensitive to long-term changes in thermal structure of lakes. This paper investigates the association of LSWT with meteorological parameters and its impact during El Nino and La Nina events over the Himalayan lake region, using Moderate Resolution Imaging Spectroradiometer (MODIS) satellite data from 2001 to 2017. The observed daytime rates of change of LSWT was −0.05°C/year whereas it was +0.01°C/year for nighttime. The cooling of lake during daytime could be attributed to increase in rainfall and decrease in solar radiation, whereas increase in nighttime LSWT is due to increasing lowest temperature. The variability in LSWT with respect to meteorological variables during El Nino Southern Oscillation period was highest for cold phase than warm phase. There was only 1% increase in LSWT in the El Nino years (2002 and 2009), due to decreased rainfall by 95% and 56% respectively. On the other hand, the LSWT decreased in strong La Nina years of 2007 (2%) and 2010 (6%) due to the drastically increased rainfall, decreased maximum temperature and solar radiation. The correlation revealed that, in addition to the increase in temperature, the LSWT warming is consistent with the decrease in rainfall and increase in solar radiation. [ABSTRACT FROM AUTHOR]

This paper examined links between U.S. soybean prices and the Dow Jones U.S. Water Index (DJUSWU). We particularly studied the impact of El Niño and La Niña events on price risk spillovers. Results showed that La Niña significantly increases the linkages between soybean and water equity markets. Based on this, we identified a new soybean hedge strategy that would be possible if a futures contract for the DJUSWU existed. This new strategy improves on the effectiveness of both a conventional naïve soybean market hedge, and a traditional time-varying hedge. The findings can be used to assist soybean agents in managing increased market risks associated with extreme weather events. [ABSTRACT FROM AUTHOR]

Weare committed to providing space to multiple perspectives,disciplines and communities shaping and deployingknowledge for water research, management andgovernance across Australasia, and continuing to fosterrigorous and healthy discussion over issues and directionsrequiring investigation. Their studydemonstrates the population-level inequalitieswhere approximately 5.3% of the basin populationidentifying as Indigenous holds less that 0.17% ofthe equivalent permitted surface water take, andIndigenous entities groundwater entitlements onlyconstitute 0.02% of all available groundwater(Hartwig, Markham, and Jackson 2021). Specifically, Hartwig, Markham, and Jackson(2021) have developed a new method for benchmarkingIndigenous water holdings and deployed itto investigate the relative holdings of surface waterand groundwater in comparison to population statisticsin the Murray-Darling Basin. These include managing issues of privacy, health concerns,levels of social acceptance and communicationstrategies (Koech, Cardell-Oliver, and Syme 2021),thus identifying pathways for future research andpractice for consideration in the design phase of suchsystems as well as in their ongoing monitoring andmaintenance. [Extracted from the article]

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In southern Africa, drier conditions are more pronounced during the El Niño Southern Oscillation (ENSO) years, triggering wildfire activity and extreme drought conditions which, individually or together, lead to loss of crop productivity, deaths of livestock and wildlife, famine, degraded ecosystems, water quality and quantity. However, the fire characteristics in relation to the emissions from biomass burning and surface properties are only examined to a limited extent in the literature, especially in Africa, where anthropogenic activities largely determine the fire activity. This study uses the available data from multi-source remote sensing platforms to (1) analyse the spatial distribution of wildfires and associated emissions during strong El Niño (2015/2016) and La Niña (2010/2011) phases in southern Africa, and (2) examine the effects of the severe El Niño and La Niña years on the relationship between the emission parameters, vegetation parameters and climatic parameters. Generally, the results suggest more emissions from the wildfire in the El Niño phase than that of the La Niña. Overall, the Pearson’s correlation clearly shows the influence and the relationship between the climate parameters themselves and also with emission parameters. [ABSTRACT FROM AUTHOR]

Lakes over the Qinghai-Tibet Plateau (TP) have large quantities and areas. As an important component of fragile plateau ecosystems, these lakes have attracted increasing attention. However, owing to the limitations of technology and methods, changes in smaller lakes on the TP have received less attention. In this study, we used Google Earth Engine (GEE) with the Analysis Ready Data (ARD) preparation framework to obtain preprocessed Sentinel-1 data covering the plateau. The D-LinkNet framework was introduced to achieve lake extraction, and the lake dataset was completed from 2016 to 2021. The lake dataset showed an area accuracy of 86.49% and Intersection over Union (IoU) of 0.72-0.99 in different regions. The findings were as follows: during the study period, the TP lakes tended to be stable after increasing, with an increase in area and number of +7.6% and +14.8%. Except for the northwest TP, the other regions show the same general trend. In particular, the Tarim Basin exhibited a lake variation pattern independent of the TP. Significantly, we found frequent lake activity in the Kunlun Mountains, Qaidam Basin, Mountain Qogir, etc. Effects of the ongoing La Niña event on the TP lakes may occur in the next few years. [ABSTRACT FROM AUTHOR]

The previous studies of upwelling within the Indonesian seas only focused on the Southeast Monsoon (SEM) season. The western coast of Sumatra Island; the southern coast of Java Island, Sunda Islands, and Sulawesi Island; the Banda Sea, the Maluku Sea, and the Arafura Sea are well-known SEM upwelling areas. However, the upwelling events during Northwest monsoon (NWM) have never been investigated. The investigation of NWM upwelling is challenging due to the broad cloud coverage, limiting the observation of infrared and visible sensors of the satellites. This study used the blended products of the satellite-based sea surface temperature (SST), chlorophyll-a (chl-a), sea level anomaly (SLA), surface wind, and rainfall to identify the NWM upwelling occurrences. Remote sensing reflectances 443 nm and 555 nm were also used to examine the influence of suspended sediment and organic matter which may bias the chl-a concentration. Along the northern coast of the Lesser Sunda Islands, the north coast of Papua Island and the Malacca Strait are the areas of NWM upwelling as denoted by the positive anomaly of chl-a, the negative anomaly of SST, and the negative anomaly of SLA. Focusing on the area along the northern coast of the Lesser Sunda Islands, the NWM upwelling is generated by offshore Ekman Mass Transport that reduces SST and increases chl-a. From 2010 onwards, El Niňo Southern Oscillation has a more consistent effect on the NWM upwelling than Indian Ocean Dipole. El Niňo (La Niňa) tends to weaken (strengthen) upwelling. The magnitude of NWM upwelling is weaker than SEM upwelling. [ABSTRACT FROM AUTHOR]

Copyright of Neotropical Biodiversity is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

It has been widely known that the coastal upwelling along the southern coast of Java is generated by southeasterly wind which induces offshore Ekman Mass Transport (EMT) during southeast monsoon. However, the variability of EMT has not been fully described in previous studies. The present study investigated the variability of Ekman dynamics which consist of EMT and Ekman Pumping Velocity (EPV) along the southern coast of Java, based on remotely sensed data. We demonstrated the incongruity between the distribution of southeasterly wind speed and sea surface temperature (SST) during southeast monsoon which is related to the distribution of Ekman dynamics. Offshore EMT at the western region of the southern coast of Java is stronger than offshore EMT at the eastern region. However, stronger offshore EMT at the western part is inhibited by downwelling EPV while weaker offshore EMT at the eastern part is accelerated by upwelling EPV. Consequently, SSTs at the eastern parts are lower than those at the western parts. Thus, the changes of offshore EMT intensity from eastern to western parts are balanced by their EPV distributions which explain the incongruity between the distribution of wind speed and SST during southeast monsoon. On an interannual timescale, the combination of La Niña and negative Indian Ocean Dipole (IOD) events tends to weaken offshore EMT and EPV which reduce the intensity of Chl-a bloom and SST cooling during southeast monsoon season. Furthermore, ENSO has a less significant impact on the Ekman dynamics variability than IOD. [ABSTRACT FROM AUTHOR]

In this research, the Bayesian quantile regression model is applied to investigate the teleconnections between large oceanic–atmospheric indices and drought standardized precipitation index (SPI) in Iran. The 12-month SPI time series from 138 synoptic stations for 1952–2014 were selected as the drought index. Three oceanic–atmospheric indices, the North Atlantic Oscillation (NAO), the Southern Oscillation Index (SOI) and the Multivariate El Niño/Southern Oscillation Index (MEI), were selected as covariates. The results show that NAO has the weakest impact on drought in different quantiles and different regions in Iran. La Niña conditions amplified droughts through all SPI quantiles in western, Caspian Sea coastal regions and southern regions. The positive phase of MEI significantly modulates low SPI quantiles (i.e. drought conditions) throughout the Zagros region, Caspian Sea coastal regions and southern regions. The study shows that the effect of large oceanic–atmospheric indices have heterogeneous impacts on extreme dry and wet conditions. [ABSTRACT FROM AUTHOR]

The influence of the El Niño Southern Oscillation (ENSO) phenomenon on monthly mean river flows of 12 rivers in the extreme south of South America in the 20th century is analysed. The original dataset of each river is divided into two subsets, i.e. warm ENSO events or El Niño, and cold ENSO events or La Niña. The elements of the subsets are composites of 24 consecutive months, from January of the year when the ENSO event begins to December of the following year. The ENSO signal is analysed by comparing the monthly mean value of each subset to the long-term monthly mean. The results reveal that, in general, monthly mean El Niño (La Niña) river flows are predominantly larger (smaller) than the long-term monthly mean in the rivers studied. The anomalies are more evident during the second half of the year in which the event starts and the first months of the following year. [ABSTRACT FROM AUTHOR]

We use regression analysis to assess the potential welfare impacts in rural Indonesia of two types of shock: a delay in monsoon onset; and a significant shortfall in rain during the 90-day post-onset period. Focusing on households with family farm businesses, we find that a delay in monsoon onset does not have a significant effect on the welfare of rice farmers. However, rice farm households located in areas exposed to low rainfall following the monsoon are negatively affected. Such households appear to be able to protect their food expenditure in the face of weather shocks, but at the expense of their non-food expenditure. We also use propensity score matching to identify community programs that might moderate the impact of this type of shock. We find that access to credit and public works projects has the strongest moderating effect. This is an important consideration for the design and implementation of adaptation strategies. [ABSTRACT FROM AUTHOR]

The ever-growing human population and the changing food habits of the expanding middle class in emerging economies with more and more advanced technological needs, along with foreseeable changes in climate (global warming) due to intensified human activity may exacerbate the occurrence and magnitude of droughts all over the world. Both this generation and future generations are left vulnerable to droughts that could have serious global consequences. Droughts are already an integral part of global climate variability, but their impact can be mitigated significantly by proactive risk management planning and preparedness emphasizing increase in water supplies with appropriate reduction in demands, strengthening regulatory framework, education, emergency responses and community rehabilitation services. Sustainable mitigation initiatives are needed to protect life and manage risks and damages to property, agriculture, industries, ecological biodiversity and natural resources. Forensic applications can help in many ways, for example, to understand interaction between components of hydrologic cycle, to determine their origin and history, in land use classification, to locate recharge areas, and in the management of water quality, as well as to determine the time of release, to identify the sources of pollution and dominant ongoing biochemical reactions, to resolve disputes, and to synthesize missing historic data that are so critical in the planning for worst droughts. Weather forecasting capabilities can reduce uncertainties and help in drought preparedness and mitigation strategies. This article reviews global weather pattern and interactions as well as coupled ocean-land-atmosphere phenomenon (El Niño Southern Oscillation and/or La Niña [ENSO] ENSO) causing interannual global climate variability, drought preparedness planning and policies, and mitigation strategies to conserve water, enhance water use efficiencies, to promote sustainable socioeconomic development, and to preserve values of natural resources. Potential applications of classic and emerging forensic fingerprinting techniques and materials to enhance and harness diverse sources of water and address growing water needs now and in the future are also discussed. Finally, an innovative sustainable drought management strategy is proposed. [ABSTRACT FROM PUBLISHER]

Descriptions of tropical instability wave (TIW) characteristics in the tropical Pacific Ocean as a function of the large‐scale climate conditions and interannual variability, such as the El Niño southern oscillation, are made based on satellite data. As others have found, the TIW ocean–atmosphere coupling is caused by atmospheric boundary layer instability and mixing. Our observational investigation extends some of these previous findings and suggests that this mechanism of coupled variability of the wind and sea surface temperature may occur not only during La Niña years, when TIWs are more active, but whenever the TIWs are active. The sea surface temperature and height anomaly covariability phase shift might occur also independent of the TIW season activity. There is evidence that TIW activity increases when under strengthened wind stress conditions either in La Niña years or, by analogy , when oceanic numerical simulations are carried out with stronger wind stress. Observational results show larger TIW wavelengths and shorter periods when the ocean is under the action of strengthened wind stress. On this observational study this occurs when La Niña conditions prevail on the equatorial Pacific. [ABSTRACT FROM AUTHOR]

Interannual variations of sea level along the Bangladesh coast are quite pronounced and often dominate the long-term sea level trends that are taking place. The El Niño/Southern Oscillation (ENSO) induced variation is an important component of interannual mode of variations. The present article deals with the relationship between the sea level variations along the Bangladesh coast and the Southern Oscillation phenomenon. The mean tide level data of monsoon season (June to September) pertaining to Hiron Point (in Sundarbans) and Char Changa (on the mouth of Meghna River) have been analyzed and correlated to the Southern Oscillation Index (SOI). The annual variation of mean tide level in the coastal areas of Bangladesh reveals that the tide level reaches its peak during the monsoon season. The maximum tide level during the calendar year is recorded in August. Thus, it is not surprising that the inundation of the coastal belt of Bangladesh due to the floods is most common during the summer monsoon season, especially from July to September. Therefore, the sea level variations during the monsoon are of paramount importance to Bangladesh. The results of the present study show that both at Hiron Point and Char Changa there is a substantial difference between the mean tide level during the El Niño and La Niña monsoons. The mean tide level at Hiron Point is higher by about 5 cm during August of La Niña years as compared to that during the El Niño years. The difference at Char Changa, which is located at the mouth of Meghna River, is much higher. This is probably due to the increased fresh water discharge into the Meghna River during La Niña years. Thus at the time of crossing of a monsoon depression, the chances of widespread inundation are higher during a La Nin~a year as compared to that during an El Niño year. The Correlation Coefficients (CCs) between Mean Tide Levels (MTLs) at Hiron Point and Char Changa and the SOI during September (at the end of monsoon) are +0.33 and +0.39 respectively. These CCs are statistically significant at 90% and 95% levels, respectively. These results may find applications in the preparedness programs for combating sea level associated disasters in Bangladesh. [ABSTRACT FROM AUTHOR]