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Because of the direct link between sea temperature and aquatic biodiversity, there is a need to analyze the temporal changes in sea surface temperature in various water bodies, especially the semi-enclosed ones. There has been substantial research undertaken on time series analysis as a powerful technique for studying the characteristics of long-term SST changes at regular time intervals. The present paper aimed to examine the monthly-averaged MODIS SST data (2001– 2019) over Kuwait Bay, i.e., the northwestern corner of the Arabian Gulf. Because different approaches can yield different results, the analysis of the SST time series was conducted using time and frequency domains. The preliminary analysis of the time series reported a significant SST peak in August 2010 that reached nearly 34.2 °C (SD = 0.17 °C) due to the moderate-intensity El Niño event in 2010. However, in the preceding year, we observed a cool SST anomaly in the range of –0.5 °C to –2.4 °C. The SMK trend test found that monthly climatological SST in September exhibited a significant upward trend (S9 = 103, r = 0.6, P = 0.0004). Pettitt’s change-point test indicated a significant change in the central tendency of SST data after April 2012. The annual periodicity of the SST in Kuwait Bay was constant over the 19 years. Furthermore, a very weak periodicity of 6-month has been barely noticed. Our present results provide large-scale guidance that affirms the importance of highlighting the severe SST fluctuations in Kuwait’s water to understand and improve its marine environmental status. [ABSTRACT FROM AUTHOR]

The impacts of local-scale temperatures and winds on bull kelp (Nereocystis luetkeana) vary along a coastal gradient, while also being influenced by corresponding global-scale oceanic conditions. Around Vancouver Island and the Gulf Islands, BC, Canada, bull kelp floating canopies were mapped using high-resolution imagery from 2005 to 2022, whereas the largest kelp bed of the area wasmapped withmedium-resolution imagery spanning from1972 to 2022. In order to understand spatial patterns of kelp resilience, the abiotic characteristics were used to organize the coastline into four clusters, ranging fromthe coldest and most exposed coast to a more sheltered and warmer location. Additionally, localscale sea surface temperatures, winds, andmarine heatwaves were categorized by global-scale temporal conditions defined by the positive/negative oceanic oscillations of the Oceanic Niño Index (ONI) and Pacific Decadal Oscillation (PDO). Comparing spatial and temporal categories, we observed that years with positive ONI and PDO, in particular the 2014-2019 period, concentrated most of themarine heatwaves and the spring temperature peaks. However, there are some indications of an underlying long-termtrend. During the period 2020-2022, when ONI and PDO were negative, summer temperatures kept increasing and wind displayed a higher frequency of extreme events. Mapped kelp showed different trends to these stressors: the coldest and most exposed area showed a constant presence of kelp during the entire period, even dating back to 1972. Warmer and semi-sheltered coasts increased in kelp percentage cover after the positive ONI +PDO period of 2014-2019, and the coasts facing the Strait of Georgia displayed a lower kelp percentage cover than the other clusters. In summary, bull kelp was resilient in the study area, but for different reasons: colder and more exposed coasts had the most favorable conditions for kelp, but warmer and more sheltered coastal kelp beds may have benefited from wind-wave forcing. [ABSTRACT FROM AUTHOR]

The Arabian Gulf is a warm (summer SST > 30 °C) and hypersaline (salinity > 40 psu at any time) marginal sea of the Indian Ocean. This paper reports on a 3-year study of seasonal and spatial changes of primary production and associated physico-chemical and biological parameters in the coastal waters of Saudi Arabia in the western Arabian Gulf. The primary production rates were low and yet showed a seasonality, with a major spring peak and a minor autumn peak, and a possible significant role for heterotrophs. While the strong relationships between the net changes of carbon uptake and nutrients between seasons showed a control of primary production by the availability of nutrients, the decrease in primary production between spring and summer when nutrients continued to increase suggests that the primary production at this time could have been controlled by higher ambient temperatures and intensities of incident light. • This Ms presents data, for the first time, on nutrients and primary production in a large sea area of the Arabian Gulf. • The waters are oligotrophic, with low rates of primary production. • Nutrients play a major role in controlling primary production. • Sea surface temperature and incident light may negatively influence primary production between spring and summer. • Increased anthropogenic inputs may render eutrophic specific locations of this pristine sea area. [ABSTRACT FROM AUTHOR]

Climate models typically have a cold sea surface temperature (SST) bias for the Arabian Sea, which regulates the Indian monsoon system as a water vapor source. Since the SST for the Arabian Sea is critical for the Indian monsoon, a better understanding of the processes that affect the SST is required. In this study, the effects of mesoscale oceanic variability on simulations of the Arabian Sea SST and Indian summer monsoon precipitation were investigated based on a comparison of climate model experiments in which non-eddying and eddy-permitting ocean components are coupled. In the eddy-permitting model, warm water advection driven by mesoscale variability near the Gulf of Aden and the Gulf of Oman increases the SST in the western Arabian Sea. Lateral eddy heat transport enhances warm water outflows to the Arabian Sea and suppresses surface water cooling by coastal upwelling during the southwestern monsoon season. Furthermore, a sensitivity experiment shows the primary importance of resolving oceanic mesoscale eddies and the secondary importance of resolving the Persian Gulf and Red Sea for the Arabian Sea SST. Also, the summer monsoonal precipitation decreases (increases) over the southeastern Arabian Sea (western and northern India) in the eddy-permitting model due to enhancement of wind convergence in the lower troposphere. Atmospheric general circulation model experiments indicate that the precipitation difference is partly caused by SST changes over the western Arabian Sea. The findings imply that the ocean resolution of climate models is a key factor in efficiently simulating the Indian monsoon. [ABSTRACT FROM AUTHOR]

The knowledge of the geographical distribution and habitat preferences of marine species is the key to protecting marine ecosystems. Modeling the distribution of marine species through environmental variables is an essential step to understanding and reducing climate change effects on marine biodiversity and related human populations. In this study, the present distributions of commercial fishes including Acanthopagrus latus, Planiliza klunzingeri, and Pomadasys kaakan were modeled using the maximum entropy (MaxEnt) modeling technique and a set of 22 environmental variables. In total, 1531 geographical records belonging to three species were extracted from online databases Ocean Biodiversity Information System (OBIS, 829 records, 54%), Global Biodiversity Information Facility (GBIF, 17 records, 1%), and literature (685 records, 45%) during September to December 2022. The findings showed the values of area under the receiver operating characteristic (ROC) curve (AUC) above 0.99 for all species indicating the high performance of this technique to reflect the actual distribution of species. Environmental factors such as depth (19.68%), sea surface temperature (SST) (19.40%), and wave height (20.71%) were the strongest environmental predictors determining the present distribution and habitat preferences of the three commercial fish species. The Persian Gulf, Iranian coasts of the Sea of Oman, North Arabian Sea, North-East areas of the Indian Ocean, and North coasts of Australia are among the areas with ideal environmental conditions for the species. For all species, the percentage of habitats with high suitability (13.35%) was higher compared to habitats with low suitability (6.56%). However, a high percentage of species occurrence habitats had unsuitable conditions (68.58%) showing the vulnerability of these commercial fishes. Significant management strategies are needed to protect preferred habitats to minimize the effect of fishery and climate change on the population stocks of these commercial fishes. [ABSTRACT FROM AUTHOR]

This study investigates relationships between the twenty large-scale climate signals and the precipitation variability during 1960–2018 in Iran. The twenty large-scale climate indicators include atmosphere-ocean teleconnections as well as El Niño-Southern Oscillation (ENSO) signals, and Pacific and Atlantic ocean Sea Surface Temperature (SST). Wavelet Coherence Analysis (WCA) and Pearson correlation analysis were applied to detect the impact of climate signals on Iran's monthly precipitation and also the precipitation of one mountainous region in Iran as a verification example. The results revealed that (a) the significant wavelet coherence and the phase difference between monthly precipitation and climate signals were highly variable in time and periodicity, (b) WCA shows the signals that are leading and most linked to Iran's precipitation at inter-annual scales are Extreme Eastern Tropical Pacific SST(5 ∘ S-5 ∘ N, 170 ∘ -120 ∘ W) (Niño 4), Western Pacific Index (WP), Tropical Southern Atlantic Index (TSA) and Western Hemisphere Warm Pool (WHWP), respectively, and at decadal and inter-decadal scales are Arctic Oscillation (AO), Atlantic Meridional Mode (AMM), and Southern Oscillation Index (SOI), respectively, (c) The WCA results for mountains region precipitation are almost consistent with the results of the country precipitation for all signals except AMM, (d) Iran's precipitation has a statistically significant positive correlation with Niño signals, and a negative one with SOI and TSA based on Pearson correlation analysis, (e) in the most recent decade, the coherence between precipitation and large-scale climate signals has declined in decadal and inter-decadal scales, and an unstable coherence has emerged in the annual scale. [ABSTRACT FROM AUTHOR]

The present study investigated the significant sea surface temperature (SST) warming trend during the summer season over the Arabian Gulf (AG) and its links with the large-scale atmospheric driver, namely, the Atlantic multidecadal oscillation (AMO), from 1900 to 2021. The link between the AMO and the AGs oceanic circulations has received little scientific attention. It has been found that there is a significant spatial positive trend, with a maximum of up to 0.6 °C per decade over the far northern end, while the time series trend shows a significant shift after 1995, with an average value of about 0.36 °C per decade. The spatial trend in the AG is eight times and four times higher than the global value from 1980 to 2005 using HadISST and OISST, respectively. The AMOs significant role in the AGs SST significant warming trend has been confirmed by the spatial and temporal correlation coefficient, which is above 0.50 and 0.48, respectively, with statistical significance at the 99% level. The underlying mechanisms that explained the AMO-related AGs SST decadal variability can be explained as follows: when the AMO is in a positive phase, the surface northwesterly wind weakens, leading to (1) less advection of the relatively cold air masses from Southern Europe to the AG and surrounding areas, (2) less evaporation, and thus less surface cooling (3); thus, this enhances the water masses stratification and decreases the upwelling process, and vice versa occurs for the negative phase. For the air temperature, the positive AMO phase coincides with the occurrence of warm air masses covering all of the Arabian Peninsula, North Africa, and Southern Europe. These processes prove that the AMO is a possible candidate for the AGs SST decadal variability, hence enabling a better evaluation of future climate scenarios for this important region. Our results provide initial insights into the AMO-driven spatiotemporal variability in the SST over the AG and prove that the relation is nonstationary over time. Further analyses are required to explore whether the impacts of the AMO are extended to other oceanic variables such as evaporation rate, heat transport, etc. [ABSTRACT FROM AUTHOR]

Copyright of Spatial Planning is the property of University of Isfahan 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.)

The sensitivity of a shelf sea model of the Gulf area to changes in the bathymetry, lateral and vertical resolution, vertical coordinates and river and atmospheric forcing is explored. Two new Gulf models with a resolution of 1.8 km, named GULF18-3.6 and GULF18-4.0, differing only in the vertical coordinate system and the NEMO code base employed (NEMO-3.6 and NEMO-4.0.4, respectively) are introduced. We compare them against the existing 4 km PGM4 model, which is based on NEMO-3.4 and is developed and used by the Met Office. PGM4 and GULF18-3.6 use similar types of quasi-terrain-following vertical levels, while GULF18-4.0 employs the multi-envelope method to discretise the model domain in the vertical direction. Our assessment compares non-assimilative hindcast simulations of the three Gulf models for the period 2014–2017 against available observations of tides, hydrography and surface currents. Numerical results indicate that both high-resolution models have higher skill than PGM4 in representing the sea surface temperature and the water column stratification on the shelf. In addition, in the proximity of the shelf break and the deep part of the domain, GULF18-4.0 generally presents the highest accuracy, demonstrating the benefit of optimising the vertical grid for the leading physical processes. For the surface currents, the three models give comparable results on the shelf, while the higher-resolution models might be prone to the double-penalty effect in deeper areas. For the tides, PGM4 has a better skill than GULF18 models, and our tidal harmonic analysis suggests that future work may be needed in order to get real benefit from using a more realistic bottom topography, as in the case of the GULF18 models. [ABSTRACT FROM AUTHOR]

Tropical cyclones (TC) are one of the biggest natural hazards with significant threat to life and property due to storm surge, flooding and extreme winds. Combined, these hazards substantially increase the potential for loss of life and damage especially in populated landfall‐locations such as the countries on the Arabian Gulf and Sea of Oman. Hence, it is important to identify the factors that modulate the trajectory of TC in order to better predict their lifetime and dynamics. Since 1900, only two TCs moved into the Sea of Oman and made landfall on the southeastern coast of the Arabian Peninsula (AP): TC Shaheen in 2021 and Gonu in 2007. In this study, the mechanisms behind the exceptional trajectories of these two TCs are investigated. Both TCs developed during the active phase of the Madden‐Julian Oscillation, and benefited from above‐average sea surface temperatures (SSTs), ocean heat content and reduced vertical wind shear. Their paths over the Indian Ocean were controlled by large‐scale forcings, whereas regional‐scale processes, such as the local SST gradients and the Arabian Heat Low (AHL) defined their trajectories near landfall location over the AP. An exceptionally deep AHL was present during these events. The AHL is found to interact two‐way with TCs: its associated circulation drags the TCs inland while the TCs, through the advection of cooler marine‐air inland, cause the collapse of the AHL. It is recommended to account for the AHL as fluctuations in its position and strength can determine where future TCs make landfall. Key Points: Cyclones Shaheen and Gonu developed in the active phase of the Madden‐Julian Oscillation and in a La Nina state in the northern Indian OceanPositive surface and subsurface ocean temperature anomalies fueled the storms and played important role in their pathsAn abnormally deep Arabian Heat Low over the Arabian Peninsula dragged the cyclones inland and modulated their exceptional trajectories [ABSTRACT FROM AUTHOR]

Current seawater temperatures around the northeastern Arabian Peninsula resemble future global forecasts as temperatures > 35 °C are commonly observed in summer. To provide a more fundamental aim of understanding the structure of wild populations in extreme environmental conditions, we conducted a population genetic study of a widespread, regional endemic table coral species, Acropora downingi, across the northeastern Arabian Peninsula. A total of 63 samples were collected in the southern Arabian/Persian Gulf (Abu Dhabi and Qatar) and the Sea of Oman (northeastern Oman). Using RAD-seq techniques, we described the population structure of A. downingi across the study area. Pairwise G'st and distance-based analyses using neutral markers displayed two distinct genetic clusters: one represented by Arabian/Persian Gulf individuals, and the other by Sea of Oman individuals. Nevertheless, a model-based method applied to the genetic data suggested a panmictic population encompassing both seas. Hypotheses to explain the distinctiveness of phylogeographic subregions in the northeastern Arabian Peninsula rely on either (1) bottleneck events due to successive mass coral bleaching, (2) recent founder effect, (3) ecological speciation due to the large spatial gradients in physical conditions, or (4) the combination of seascape features, ocean circulation and larval traits. Neutral markers indicated a slightly structured population of A. downingi, which exclude the ecological speciation hypothesis. Future studies across a broader range of organisms are required to furnish evidence for existing hypotheses explaining a population structure observed in the study area. Though this is the most thermally tolerant acroporid species worldwide, A. downingi corals in the Arabian/Persian Gulf have undergone major mortality events over the past three decades. Therefore, the present genetic study has important implications for understanding patterns and processes of differentiation in this group, whose populations may be pushed to extinction as the Arabian/Persian Gulf warms. [ABSTRACT FROM AUTHOR]

The Arabian Sea (AS) hosts one of the most intense oxygen minimum zones (OMZs) in the world. Observations suggest a decline in O 2 in the northern AS over the recent decades accompanied by an intensification of the suboxic conditions there. Over the same period, the local sea surface temperature has risen significantly, particularly over the Arabian Gulf (also known as Persian Gulf, hereafter the Gulf), while summer monsoon winds may have intensified. Here, we simulate the evolution of dissolved oxygen in the AS from 1982 through 2010 and explore its controlling factors, with a focus on changing atmospheric conditions. To this end, we use a set of eddy-resolving hindcast simulations forced with winds and heat and freshwater fluxes from an atmospheric reanalysis. We find a significant deoxygenation in the northern AS, with O 2 inventories north of 20 ∘ N dropping by over 6 % per decade between 100 and 1000 m. These changes cause an expansion of the OMZ volume north of 20 ∘ N at a rate of 0.6 % per decade as well as an increase in the volume of suboxia and the rate of denitrification by 14 and 15 % per decade, respectively. We also show that strong interannual and decadal variability modulate dissolved oxygen in the northern AS, with most of the O 2 decline taking place in the 1980s and 1990s. Using a set of sensitivity simulations we demonstrate that deoxygenation in the northern AS is essentially caused by reduced ventilation induced by the recent fast warming of the sea surface, including in the Gulf, with a contribution from concomitant summer monsoon wind intensification. This is because, on the one hand, surface warming enhances vertical stratification and increases Gulf water buoyancy, thus inhibiting vertical mixing and ventilation of the thermocline. On the other hand, summer monsoon wind intensification causes a rise in the thermocline depth in the northern AS that lowers O 2 levels in the upper ocean. Our findings confirm that the AS OMZ is strongly sensitive to upper-ocean warming and concurrent changes in the Indian monsoon winds. Finally, our results also demonstrate that changes in the local climatic forcing play a key role in regional dissolved oxygen changes and hence need to be properly represented in global models to reduce uncertainties in future projections of deoxygenation. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Zoological Systematics & Evolutionary Research is the property of Hindawi Limited 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.)

This paper presents the paleocurrent evolution of the Persian Gulf deep water (PGDW) during the last 5000 years using faunal (foraminiferal assemblage) and non-faunal (magnetic susceptibility, sediment grain size, number of coarse relict particles and physicochemical characteristics) indicators from a 133 cm long core retrieved from the Strait of Hormoz (SH). Our results suggest that the precession-related insolation change and solar variability induced long-term and short-term sea surface temperature (SST) rise and fall resulted in variation of PGDW outflow strength. Two periods of decreasing SST (5000–4300 and 2000–1450 cal yr BP), accompanied by wetter conditions in the Middle East, are related to the reduction of the PGDW current velocity. A combination of high sedimentation rate (0.72 mm yr−1, due to high terrigenous input) with a relatively low bottom flow energy cause the settling of finer sediments providing a favourable environment for the expansion of benthic foraminifera (dominated by infaunal taxa). On the contrary, the PGDW current velocity strengthens in the periods of SST increase (4300–2000 and 1450 cal yr BP to present) with decreasing sedimentation rate (0.15–0.34 mm yr−1, due to low river discharge). During both periods of high-velocity bottom currents, the benthic foraminifera accumulation rate decreases. However, as the PGDW brings a relatively high amount of dissolved oxygen (3.25 mg/l in summer and 4.79 mg/l in winter) and phytodetritus particles, compared to the surrounding water, some particular foraminifera (especially robust suspension feeder epifaunal taxa) evolved. SST increase, intensified by anthropically caused global warming, may lead to PGDW intensification in the future. • Since the mid-Holocene, PGDW intensity has been under influence of the continental climate of SW Asia and the Arabian Sea SST. • SST intensification (4500 to 3000 and 1400 cal yr BP to present), causes increasing bottom current energy of the Strait of Hormoz and decreasing river discharges. • Although high energy bottom currents provide a hostile environment for the benthic fauna, it brings high DO content bottom waters. [ABSTRACT FROM AUTHOR]

Daily values of precipitation in southwestern parts of Iran along with the corresponding Madden–Julian oscillation (MJO) phase are analysed to introduce some auxiliary indicators that can identify the wet and dry spells within a particular MJO phase. As a case study, the identification procedure focuses on phase 1 during the rainy season (Nov–Apr). The study shows that this phase contains two opposite spells, referred to as spells with pervasive precipitation (SWPP) and spells with widespread dryness (SWWD). Although the precipitation characteristics are essentially different between SWPP and SWWD, their associated MJO indices are found statistically identical. Therefore, the MJO–precipitation relationship fails to identify the wet/dry spells within an MJO phase. To resolve this deficiency, other climate indicators, which behave differently between these two spells, are introduced. The westward moisture flux over equatorial parts of the Indian Ocean and the northeastward moisture flux over the North African tropics are up to seven times stronger in the SWPP compared to SWWD. The dominance of a strong cyclonic (anticyclonic) circulation over the eastern side of the Mediterranean Sea and the negative (positive) west–east temperature gradient over southern parts of Iran are introduced as SWPP (SWWD) indicators. The study reveals that the SWPP (SWWD) coincides with a strong (weak) convection dipole that resembles the positive Indian Ocean dipole. The intensified (weakened) wind speed in the subtropical jet stream and persistence of the jet‐exit‐regions above Iran (Egypt and Saudi Arabia) are other SWPP (SWWD) indicators. Negative (positive) anomalies of sea surface temperature over the North Atlantic Ocean, the Black, Mediterranean, and Caspian Seas, as well as the Persian Gulf, signify the prevalence of the SWPP (SWWD). To the best of our knowledge, this is the first time that auxiliary indices are utilized to improve the MJO–precipitation relationship in southwestern Iran. [ABSTRACT FROM AUTHOR]

Climate change has led to major shifts in the timing of biological events, with many studies demonstrating earlier phenology in response to warming. However, few of these studies have investigated the effects of climate change on the phenology of larvae in marine species. Phenological shifts can result in mismatches between consumers and prey and hence affect growth and survival of individuals, and ultimately population demography. We investigated the temporal changes in phenology and abundance of the larvae of dominant brachyuran crabs in the southern Gulf of St. Lawrence (eastern Canada) based on plankton collections spanning 1982–2012. The Gulf of St. Lawrence has warmed since the early 1990s, and our analyses revealed that larvae of snow crab (Chionoecetes opilio) and toad crabs (Hyas spp.) exhibited a significant trend towards earlier phenology over the 30‐year study period. This shift in phenology appeared to be a consequence of the effect of climate warming on both the timing of hatching and larval development rate. Larval abundance responded differently by crab taxon to climate warming, likely due to differences in thermal tolerance. The warming trend was unfavourable to snow crab, which is the most cold‐adapted and stenothermic of the taxa examined in this study. The abundance of snow crab larvae was lower when sea ice retreat occurred earlier than day 110 of the year and sea surface temperature was higher than 8.5°C. On the other hand, larval abundance of rock crab (Cancer irroratus), which prefers higher temperatures, was positively related to surface temperature. [ABSTRACT FROM AUTHOR]

To answer the question "what has changed the surface temperatures of water bodies around Iran under climate change conditions," Moderate Resolution Imaging Spectroradiometer (MODIS) sea surface temperature (SST) data with 9.2-km spatial resolution and monthly time step were evaluated. A significant increasing trend was obtained using Pearson's correlation coefficient and Mann-Kendall trend test on data from the Caspian Sea (June) and the Southern Gulfs (September). High correlations of 0.69 and 0.97 between remotely sensed data and ERA-Interim reanalysis data were also obtained for June and September, respectively. To assess the impact of some climatic parameters on SST variability in those two months, zonal and meridional wind at 10 m, wind speed at 10 m, air temperature at 2 m, and mean sea level pressure were evaluated. High correlations between meridional wind and the Southern Gulf SST, and meridional wind and Caspian SST were −0.86 and 0.75, respectively. Moreover, the results showed an important role of air temperature (0.96) and sea level pressure (−0.77) in the rising temperature trends of the Southern Gulfs. Wind speed was also detected in both regions as a booster of the trend. [ABSTRACT FROM AUTHOR]

Iran faces a water shortage crisis due to its long and frequent droughts and rapid population growth. In this study, moisture sources have been determined in 161 precipitation events from 12 stations using a Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model. Ten main moisture sources have been identified among which the Persian Gulf and the Persian Gulf with terrestrial sources are dominant. Backward trajectory outputs demonstrate that the precipitation events in the stations in the north of Iran originate mostly from the Caspian Sea and terrestrial sources. These precipitation events are mostly plotted on the Global Meteoric Water Line (GMWL) or between GMWL and Eastern Mediterranean Meteoric Water Line (EMMWL). Precipitation events in the middle and south of Iran stations receive moisture mostly from the Persian Gulf and terrestrial sources and they are mostly plotted on EMMWL. Linking backward trajectory models with precipitation events (δ 18O and δ 2H) determines the general isotope characteristics of each moisture source. Most of the precipitation events originate from high sea surface temperature (SST) water bodies and are plotted on EMMWL. However, precipitation events originating from lower SST water bodies are mostly plotted on GMWL and between GMWL and EMMWL. Plotting the average (δ 18O and δ 2H) in the studied stations on the meteoric water lines of the regions located on the dominant air masses trajectories toward Iran confirms the dominant moisture sources for the studied stations and also other obtained results by stable isotope technique and HYSPLIT model in this study. [ABSTRACT FROM AUTHOR]

Climate change–reflected in significant environmental changes such as warming, sea level rise, shifts in salinity, oxygen and other ocean conditions–is expected to impact marine organisms and associated fisheries. This study provides an assessment of the potential impacts on, and the vulnerability of, marine biodiversity and fisheries catches in the Arabian Gulf under climate change. To this end, using three separate niche modelling approaches under a ‘business-as-usual’ climate change scenario, we projected the future habitat suitability of the Arabian Gulf (also known as the Persian Gulf) for 55 expert-identified priority species, including charismatic and non-fish species. Second, we conducted a vulnerability assessment of national economies to climate change impacts on fisheries. The modelling outputs suggested a high rate of local extinction (up to 35% of initial species richness) by 2090 relative to 2010. Spatially, projected local extinctions are highest in the southwestern part of the Gulf, off the coast of Saudi Arabia, Qatar and the United Arab Emirates (UAE). While the projected patterns provided useful indicators of potential climate change impacts on the region’s diversity, the magnitude of changes in habitat suitability are more uncertain. Fisheries-specific results suggested reduced future catch potential for several countries on the western side of the Gulf, with projections differing only slightly among models. Qatar and the UAE were particularly affected, with more than a 26% drop in future fish catch potential. Integrating changes in catch potential with socio-economic indicators suggested the fisheries of Bahrain and Iran may be most vulnerable to climate change. We discuss limitations of the indicators and the methods used, as well as the implications of our overall findings for conservation and fisheries management policies in the region. [ABSTRACT FROM AUTHOR]

Whitings, the manifestation of high levels of suspended fine-grained calcium carbonate particles in the water, have been reported and studied worldwide. However, the triggering mechanism of whiting occurrences remains uncertain. The current study attempted to analyze potential factors that might account for whiting occurrences in a semi-enclosed gulf (namely the Arabian/Persian Gulf, hereinafter called the Gulf). First, spatial and temporal variability of whiting events and different potential driving factors (i.e., whiting seasonality, wind-induced mixing, sea surface temperature, and bathymetry) were explored and examined for five years (2015–2020). Second, as a general indicator of whiting occurrences in the Gulf, a whiting index (WI) was developed using time-series analysis and decision tree (DT) classification algorithm. Third, the correlation between the proposed WI and the spatial coverage of various whiting events was examined. Time-series analysis showed that whiting events during the winter season are associated with high winds that lasted for several days. Nevertheless, whiting events were rarely observed despite high wind speed and increased potential for CaCO3 precipitation in summer. This finding suggests that wind-driven forces might be potential sources for mixing water columns, resuspension of CaCO3 particles, and the appearance of whiting in the Gulf. The DT classification algorithm demonstrated that a minimum WI value of 1.1 can explain the initiation of most summer and winter whiting events. Furthermore, a Pearson correlation coefficient of 0.73 was measured between WI and the extent of whiting along the UAE and Qatar coastlines in the Gulf. The proposed WI shows a simple yet effective method for identifying and estimating the extent of whiting in the Gulf. [ABSTRACT FROM AUTHOR]

Using mathematical models alone to describe the changes in the parameters characterizing the analyzed reservoir may be insufficient due to the complexity of ocean circulation. One of the ways to improve the accuracy of models is to use data assimilation based on remote sensing methods. In this study, we tested the EcoFish numerical model that was developed for the Gulf of Gdańsk area, under the FindFish Knowledge Transfer Platform. In order to improve the model results and map local phenomena occurring in the studied water, which would be difficult to simulate using only mathematical equations, EcoFish was extended with a satellite data assimilation module that assimilates the sea surface temperature data from a medium-resolution imaging spectroradiometer and an advanced ultrahigh-resolution radiometer. EcoFish was then statistically validated, which resulted in high correlations for water temperature and salinity as well as low errors in comparison with in situ experimental data. [ABSTRACT FROM AUTHOR]

Validating remotely sensed sea surface temperature (SST) is a fundamental step in establishing reliable biological/physical models that can be used in different marine applications. Mapping SST using accurate models would assess in understanding critical mechanisms of marine and coastal zones, such as water circulations and biotic activities. This study set out to validate MODIS SSTs with a spatial resolution of 1-km in the Arabian Gulf (24–30° N, 48–57° E) and to assess how well direct comparison of dual matchups and triple collocation analyses perform. For the matchup process, three data sets, MODIS-Aqua, MODIS-Terra, and iQuam, were co-located and extracted for 1-pixel box centered at each actual in situ measurement location with a time difference window restricted to a maximum of ±3 h of the satellite overpass. Over the period July 2002 to May 2020, the MODIS SSTs (N = 3786 triplets) exhibited a slight cool night-time bias compared to iQuam SSTs, with a mean ± SD of −0.36 ± 0.77 °C for Aqua and −0.27 ± 0.83 °C for Terra. Daytime MODIS SST observations (N = 5186 triplets) had a lower negative bias for both Aqua (Bias = −0.052 °C, SD = 0.93 °C) and Terra (Bias = −0.24 °C, SD = 0.90 °C). Using extended triple collocation analysis, the statistical validation of system- and model-based products against in situ-based product indicated the highest ETC-based determination coefficients ( ρ t , X 2   ≥ 0.98) with the lowest error variances ( σ ε 2   ≤ 0.32), whereas direct comparison underestimated the determination coefficients and overestimated the error estimates for all MODIS algorithms. The ETC-based error variances for MODIS Aqua/Terra NLSSTs were 0.25/0.19 and 0.26/0.32 in daytime and night-time, respectively. In addition, MODIS-Aqua was relatively more sensitive to the SST signal than MODIS-Terra at night and vice versa as seen in the unbiased signal-to-noise ratios for all observation types. [ABSTRACT FROM AUTHOR]

The Arabian Gulf is one of the regions in the world experiencing major changes due to increased economic growth rates and development practices. As a shallow water body within a hot desert, the Gulf is exposed to obvious warming in the sea surface temperatures (SST). Remotely sensed SST data were utilized to estimate decadal change in SST with a focus on coral reef locations. There is a positive trend in monthly time series SSTs, with a maximum value of about 0.7 °C/decade for the western side of the Gulf. This high trend of SST is associated with significant coral reef bleaching and it coincides with major climate/ocean interactions. Most of the Arabian countries along the Gulf have coastal developments at low-land areas of high vulnerability to sea level rise. Digital elevation models showed that there are more than 3100 km2 of coastal areas that occur at 1 m level along the Arabian countries of the Gulf. Coastal protection and conservation measures are crucial to protect low-lying coasts of urban use. [ABSTRACT FROM AUTHOR]