Trends and change points in surface and bottom thermal environments of the US Northeast Continental Shelf Ecosystem

Abstract

Temperature is an important factor in defining the habitats of marine resource species. While satellite sensors operationally measure ocean surface temperatures, we depend on in situ measurements to characterize benthic habitats. Ship‐based measurements were interpolated to develop a time series of gridded spring and fall, surface and bottom temperature fields for the US Northeast Shelf. Surface and bottom temperatures have increased over the study period (1968–2018) at rates between 0.18–0.31°C per decade and over a shorter time period (2004–2018) at rates between 0.26–1.49°C per decade. A change point analysis suggests that a warming regime began in the surface waters in 2011 centered on Georges Bank and the Nantucket Shoals; in following years, most of the Northeast Shelf had experienced a shift in surface temperature. A similar analysis of bottom temperature suggests a warming regime began in 2008 in the eastern Gulf of Maine; in following years, change points in temperature occurred further to the west in the Gulf of Maine, finally reaching the Middle Atlantic Bight by 2010. The spatial pattern in bottom water warming is consistent with well‐known oceanographic patterns that advect warming North Atlantic waters into the Gulf of Maine. The varying spatial and temporal progression of warming in the two layers suggests they were actuated by different sets of forcing factors. We then compared these trends and change points to responses of lower and higher trophic level organisms and identified a number of coincident shifts in distribution and biomass of key forage and fisheries species.

Evaluating benthic impact of the Gulf of Maine lobster fishery using the Swept Area Seabed Impact (SASI) model

“…Ongoing changes in the distribution of fishing effort may cause varying degrees of benthic disturbance that shift over time and affect the total amount of EFH that is damaged. For example, lobster fishing effort has tracked abundance shifts northeastward (Steneck and Wilson 2001;Kleisner et al 2017), attributable to rapid warming (Pershing et al 2015;Friedland et al 2020) and increased habitat suitability (Tanaka and Chen 2016;Le Bris et al 2018;Goode et al 2019;Mazur et al 2020). Additionally, limited entry to the GoM lobster fishery has shifted the age of license holders to 50-65 years old (Stoll et al 2016;Stoll 2017), few younger potential lobster fishers are replacing those that exit the fishery (Fig.…”

Effects of ocean acidification on larval Atlantic surfclam (Spisula solidissima) from Long Island Sound in Connecticut

“…By the year 2100, under the RCP 8.5 scenario (high emissions) used in climate modeling, CO 2 levels will be >1000 µatm, and under the RCP 6.0 scenario, CO 2 levels will be in the range of 720-1000 µatm (IPCC, 2014). Projected increases in CO 2 by 2100 are expected to result in a reduction of 0.2-0.4 in pH and in a 50% decline in aragonite saturation level (Ω aragonite ), a measure often used in relation to Ω because aragonite is a common form of calcium carbonate in ocean waters (Feely et al, 2004(Feely et al, , 2010Hartin et al, 2016). It has been predicted that, by the year 2300, CO 2 levels will be >2000 µatm and will correspond to an additional drop of 0.4 in pH (Feely et al, 2004(Feely et al, , 2010Hartin et al, 2016).…”

“…The findings of these studies indicate that an Ω aragonite of ~1.5 results in physiological responses in marine bivalve species. These studies focused on bivalve species that reside in estuarine water, where changes in temperature, salinity, and partial pressure of CO 2 (ρCO 2 ) can occur at daily rates (Feely et al, 2010;Dickinson et al, 2013;Duarte et al, 2013), and their results may not be applicable to coastal bivalve species.…”

“…The process of ocean acidification (OA) occurs when increased atmospheric carbon dioxide (CO 2 ) from anthropogenic activities (i.e., burning of fossil fuels and deforestation) is absorbed by ocean waters (Caldeira and Wickett, 2003;Raven et al 1 ;Doney et al, 2009). Consequently, concentrations of dissolved CO 2 and bicarbonate ions (HCO 3 − ) rise, while concentration of carbonate ions (CO 3 2− ), pH, and calcium carbonate saturation level (Ω) decline (Feely et al, 2004(Feely et al, , 2010Hönisch et al, 2012;Duarte et al, 2013). In recent years, the ocean's natural capacity for buffering, a process that normally occurs over a geologic timescale of 10,000-100,000 years, has been unable to keep pace with the rate of acidification (Hönisch et al, 2012;, resulting in a global ocean pH drop of…”

The Middle Atlantic Bight Cold Pool is warming and shrinking: Indices from in situ autumn seafloor temperatures

“…This statement). The bivariate relationships between day of year and temperature were overwhelmingly linear and have been widely used to standardize multiyear surveys (Friedland et al, 2020). However, we should note that there were a few instances where destratification caused nonlinear changes in temperature during the time periods around April 3 and October 11 but did not affect overall trends.…”