Coastlines are fundamental to humans for habitation, commerce, and natural resources. Many coastal ecosystem disasters, caused by extreme sea surface temperature (SST), were reported when the global climate shifted from warming hiatus after 1998. The task of understanding SST variations within context is an urgent matter. Our study on 1982 2013 revealed a significant cooling trend in low mid latitudes (31.4% coastlines) 1998, while 17.9% coastlines changed concurrently. reversals Northern...

The multi-temporal scales of two physical characteristics (areas and occurrence time) the Ross Sea Polynya (RSP) in Antarctica were analysed using a sea-ice concentration data set (1979–2014) derived from Scanning Multichannel Microwave Radiometer, Special Sensor Imager Sounder. Then, Ensemble Empirical Mode Decomposition (EEMD) was applied to sets decompose signals into finite numbers intrinsic mode functions residual mode: long time trend. This approach allowed us understand long-term...

Abstract The variability of the South Pacific convergence zone (SPCZ) is evaluated using ocean surface wind products derived from atmospheric reanalysis ERA-Interim for period 1981–2014 and QuickSCAT 1999–2009. From these products, indices were developed to represent SPCZ strength, area, centroid location. Excellent agreement found between two during QuikSCAT in terms spatiotemporal structures SPCZ. longer product used study variations properties on intraseasonal, seasonal, interannual,...

Synthetic aperture sonar (sas) systems are designed to observe stationary scatterers located near the sediment interface. Less commonly, a sas system may be used scattering features above in water column. The Undersea Remote Sensing (USRS) project, sponsored by Office of Naval Research, was collaborative Directed Research Initiative (DRI) focused on studying dynamic estuarine column features. During USRS DRI, researchers from multiple institutions gathered tidal at various estuaries along...

Data captured by a Synthetic Aperture Sonar (SAS) near Mobile Bay during the 2021 Undersea Remote Sensing experiment funded Office of Naval Research reveals surface bubble clouds from wave breaking events and large aggregation fish. Tools developed for using SAS data to image hydrodynamic features in water column were applied observations fish aggregation. Combining imagery height sonar array with detection tracking algorithm enables trajectories, velocities, behavior be observed. Fitting...

We examine several characteristics of the Western Pacific Warm Pool (WP) in past thirty years mixed interannual variability and climate change. Our study presents three-dimensional WP centroid (WPC) movement, heat content anomaly (HC) volume (WPV) on to decadal time scales. show statistically significant correlation between each parameter's NINO 3, 3.4, 4, SOI, PDO indices. The longitudinal component WPC is most strongly correlated with 4 (R = 0.78). depth has highest -0.6) NINO3.4. WPV...

In recent years, it has been observed that there are different types of El Niño events. The warm events can be divided into two categories: those centered in the central Pacific (CP) and eastern (EP). We examined variability western pool (WPWP) horizontal migration size from January 1982 to December 2011 by applying Ensemble Empirical Mode Decomposition (EEMD) Hilbert‐Huang Spectrum (HHS) optimally interpolated sea surface temperature (OISST) data set. analysis shows long‐term residual trend...

A high frequency (HF) AUV-mounted forward-looking sonar deployed in the shallow Long Island Sound recorded acoustic scattering measurements from large bedform ripples. The axis of transmission was horizontal and laterally oblique to ripple plane, but at wide aperture, so that broadside ripples believed be a significant contributor return. effects are explored through finite element model evaluation comparison. In this study, seafloor orders magnitude larger than wavelengths used survey....

Tidal forcing in rivers and estuaries has a large impact on the use high-frequency acoustics for bathymetric mapping. Changes sound speed profile due to changing salinity temperature conditions affect acoustic propagation, bubbles, entrained tidal flow, cause high backscattering attenuation. In this study, forward-looking, sonar was used observe estuarine dynamics near mouth of Connecticut River June 2017. The deployed REMUS 600 AUV under fresh water plume river during flood tide, lower...

Estuaries are a challenging environment to use acoustically navigated Autonomous Underwater Vehicles (AUVs) due highly variable currents, relatively shallow and bathymetry, large buoyancy changes, suspended sediments, marine biota, bubble plumes. The benefit using AUVs is their ability perform repeat automated surveys targeted sampling of features either remote control or on-board redirects. Our REMUS 100 equipped with up/down looking ADCPs, CTDs, optical backscatter sensors. Long Base Line...

Rivers and estuaries can be highly energetic present a challenging environment for sonar deployment observation. To better understand this environment, high-frequency, wide-sector forward-looking bathymetric was used to observe tidal phenomena in the lower Connecticut River June 2017. The stationary system provided Eulerian measurements of estuary complete cycle, covering large portion main channel. able map observed region differentiate between bathymetry non-stationary water column. data...