Temperature variations in the northern Gulf of Alaska across synoptic to century-long time scales

Danielson, Seth L.; Hennon, Tyler D.; Monson, Daniel H.; Suryan, Robert M.; Campbell, Robert W.; Baird, Steven J.; Holderied, Kristine; Weingartner, Thomas J.

doi:10.1016/j.dsr2.2022.105155

Cited by 23 publications

(24 citation statements)

References 71 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Sub-surface marine heat extreme events occurred throughout the timeseries but became more prevalent during the 2013-2016 marine heat wave and affected up to 80% of the shelf seafloor (Figure 10a). This subsurface marine heat wave started in 2015 and therefore later than at the surface, which is consistent with in situ observations (Danielson et al, 2022). The timing of our modeled heat waves on the shelf seafloor is similar to the timing of events found in an ocean reanalysis study (Amaya et al, 2023), although they used the 90th percentile and considered a larger shelf area (bottom grid cells shallower than 400 m), which could have led to the differences in the spatial extent and duration of the heat waves.…”

Section: Quadruple Compound Extreme Events On Shelf Seafloor Influenc...supporting

confidence: 91%

“…While several marine heat waves occurred throughout the simulation, the 2013–2016 and 2018–2020 marine heat waves lasted longer and were more extreme than the previous ones, which aligns with previous observational and modeling studies (Amaya et al., 2020; Di Lorenzo & Mantua, 2016). The 2013–2016 marine heat wave was preceded by a 7‐year‐long cold phase (Danielson et al., 2022), with frequent low Ω arag (Figures 6c and 7c) and high [H + ] (Figures 6b and 7b) extreme events that affected a large proportion of the gyre area (Figures 7a–7c; Hauri et al., 2021). Negative Ω arag extreme events also affected up to 95% of the surface water on the shelf at times (Figure 6c), whereas positive [H + ] extreme events were not as pronounced there (Figure 6b).…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

More Than Marine Heatwaves: A New Regime of Heat, Acidity, and Low Oxygen Compound Extreme Events in the Gulf of Alaska

Hauri,

Pagès,

Hedstrom

et al. 2024

AGU Advances

View full text Add to dashboard Cite

Recent marine heatwaves in the Gulf of Alaska have had devastating impacts on species from various trophic levels. Due to climate change, total heat exposure in the upper ocean has become longer, more intense, more frequent, and more likely to happen at the same time as other environmental extremes. The combination of multiple environmental extremes can exacerbate the response of sensitive marine organisms. Our hindcast simulation provides the first indication that more than 20% of the bottom water of the Gulf of Alaska continental shelf was exposed to quadruple heat, positive hydrogen ion concentration [H+], negative aragonite saturation state (Ωarag), and negative oxygen concentration [O2] compound extreme events during the 2018–2020 marine heat wave. Natural intrusion of deep and acidified water combined with the marine heat wave triggered the first occurrence of these events in 2019. During the 2013–2016 marine heat wave, surface waters were already exposed to widespread marine heat and positive [H+] compound extreme events due to the temperature effect on the [H+]. We introduce a new Gulf of Alaska Downwelling Index (GOADI) with short‐term predictive skill, which can serve as indicator of past and near‐future positive [H+], negative Ωarag, and negative [O2] compound extreme events near the shelf seafloor. Our results suggest that the marine heat waves may have not been the sole environmental stressor that led to the observed ecosystem impacts and warrant a closer look at existing in situ inorganic carbon and other environmental data in combination with biological observations and model output.

show abstract

Section: Quadruple Compound Extreme Events On Shelf Seafloor Influenc...supporting

confidence: 91%

Section: Resultsmentioning

confidence: 99%

More Than Marine Heatwaves: A New Regime of Heat, Acidity, and Low Oxygen Compound Extreme Events in the Gulf of Alaska

Hauri,

Pagès,

Hedstrom

et al. 2024

AGU Advances

View full text Add to dashboard Cite

show abstract

“…Although we found no evidence that low adult female survival in (Bond et al, 2015;Chen et al, 2021;Danielson et al, 2022). Viable pup production was annually variable (up to ~0.20) and was particularly high in 2014 for unknown reasons (Figure 5).…”

Section: Causal Mechanisms Underlying Reproductive Senescence Inmentioning

confidence: 61%

Age‐specific reproduction in female Steller sea lions in Southeast Alaska

Hastings,

Jemison,

Pendleton

et al. 2023

Ecology and Evolution

View full text Add to dashboard Cite

Age‐, region‐, and year‐specific estimates of reproduction are needed for monitoring wildlife populations during periods of ecosystem change. Population dynamics of Steller sea lions (Eumetopias jubatus) in Southeast Alaska varied regionally (with high population growth and survival in the north vs. the south) and annually (with reduced adult female survival observed following a severe marine heatwave event), but reproductive performance is currently unknown. We used mark‐resighting data from 1006 Steller sea lion females marked as pups at ~3 weeks of age from 1994 to 1995 and from 2001 to 2005 and resighted from 2002 to 2019 (to a maximum age of 25) to examine age‐, region‐, and year‐specific reproduction. In the north versus the south, age of first reproduction was earlier (beginning at age 4 vs. age 5, respectively) but annual birth probabilities of parous females were reduced by 0.05. In an average year pre‐heatwave, the proportion of females with pup at the end of the pupping season peaked at ages 12–13 with ~0.60/0.65 (north/south) with pup, ~0.30/0.25 with juvenile, and ~0.10 (both regions) without a dependent. In both regions, reproductive senescence was gradual after age 12: ~0.40, 0.40, and 0.20 of females were in these reproductive states, respectively, by age 20. Correcting for neonatal mortality, true birth probabilities at peak ages were 0.66/0.72 (north/south). No cost of reproduction on female survival was detected, but pup production remained lower (−0.06) after the heatwave event, which if sustained could result in population decline in the south. Reduced pup production and greater retention of juveniles during periods of poor prey conditions may be an important strategy for Steller sea lions in Southeast Alaska, where fine‐tuning reproduction based on nutritional status may improve the lifetime probability of producing pups under good conditions in a variable and less productive environment.

show abstract

“…As in many biomes worldwide, there is long-term warming in the NGA (Danielson et al, 2022) as well as increased freshening of surface waters (Figure 2). Together, these trends have increased water column stratification.…”

Section: Resultsmentioning

confidence: 99%

Recent Marine Heatwaves Affect Marine Ecosystems from Plankton to Seabirds in the Northern Gulf of Alaska

Strom¹

2023

Oceanog

View full text Add to dashboard Cite

Several decades of research and monitoring in the northern Gulf of Alaska (NGA) have revealed climate-related shifts in ocean temperature and salinity. Accompanying these shifts have been changes in the abundance and diversity of species, from single-celled plankton to fish, seabirds, and marine mammals. Research is documenting long-term change in the region and revealing the mechanisms by which recent marine heatwaves affect the ability of higher trophic levels to survive in these waters. Heatwaves in the northern Gulf of Alaska are likely to become longer, more frequent, and more intense, making long-term monitoring of ecosystem changes critical to understanding and predicting effects on valuable commercial fisheries and culturally significant native harvesting. In addition, documentation of change is necessary for projecting regional and global future climate scenarios and for informing climate-related policy decisions.

show abstract

Temperature variations in the northern Gulf of Alaska across synoptic to century-long time scales

Cited by 23 publications

References 71 publications

More Than Marine Heatwaves: A New Regime of Heat, Acidity, and Low Oxygen Compound Extreme Events in the Gulf of Alaska

More Than Marine Heatwaves: A New Regime of Heat, Acidity, and Low Oxygen Compound Extreme Events in the Gulf of Alaska

Age‐specific reproduction in female Steller sea lions in Southeast Alaska

Recent Marine Heatwaves Affect Marine Ecosystems from Plankton to Seabirds in the Northern Gulf of Alaska

Contact Info

Product

Resources

About