Spatial congruence between multiple stressors in the Mediterranean Sea may reduce its resilience to climate impacts
"Climate impacts on marine ecosystems may be exacerbated by other, more local stressors interacting synergistically, such as pollution and overexploitation of marine resources. The reduction of these human stressors has been proposed as an achievable way of retaining ecosystems within a “safe operating space” (SOS), where they remain resilient to ongoing climate change. However, the operability of an SOS requires a thorough understanding of the spatial distribution of these climate and human impacts. [...]"
Source: Scientific Reports
Authors: Francisco Ramírez et al.
Generality in multispecies responses to ocean acidification revealed through multiple hypothesis testing
"Decades of research have demonstrated that many calcifying species are negatively affected by ocean acidification, a major anthropogenic threat in marine ecosystems. However, even closely related species may exhibit different responses to ocean acidification and less is known about the drivers that shape such variation in different species. Here, we examine the drivers of physiological performance under ocean acidification in a group of five species of turf‐forming coralline algae. [...]"
Source: Global Change Biology
Authors: Allison K. Barner et al.
The Ocean is losing its breath: declining oxygen in the world's ocean and coastal waters; summary for policy makers
"Oxygen is critical to the health of the ocean. It structures aquatic ecosystems, impacts the biogeochemical cycling of carbon, nitrogen and other key elements, and is a fundamental requirement for marine life from the intertidal zone to the greatest depths of the ocean." [...]
Source: UNESCO (UNESDOC)
Authors: Denise Breitburg et al.
Hazards of decreasing marine oxygen: the near-term and millennial-scale benefits of meeting the Paris climate targets
"Ocean deoxygenation is recognized as key ecosystem stressor of the future ocean and associated climate-related ocean risks are relevant for current policy decisions. In particular, benefits of reaching the ambitious 1.5 °C warming target mentioned by the Paris Agreement compared to higher temperature targets are of high interest. Here, we model oceanic oxygen, warming and their compound hazard in terms of metabolic conditions on multi-millennial timescales for a range of equilibrium temperature targets. [...]"
Source: Earth System Dynamics
Authors: Gianna Battaglia and Fortunat Joos
Ocean science research is key for a sustainable future
"Human activity has already affected all parts of the ocean, with pollution increasing and fish-stocks plummeting. The UN’s recent announcement of a Decade of Ocean Science provides a glimmer of hope, but scientists will need to work closely with decision-makers and society at large to get the ocean back on track. [...]"
Source: Martin Visbeck
Author: Nature Communications
Read the full article here.
Oceans suffocating as huge dead zones quadruple since 1950, scientists warn
Areas starved of oxygen in open ocean and by coasts have soared in recent decades, risking dire consequences for marine life and humanity
"Ocean dead zones with zero oxygen have quadrupled in size since 1950, scientists have warned, while the number of very low oxygen sites near coasts have multiplied tenfold. Most sea creatures cannot survive in these zones and current trends would lead to mass extinction in the long run, risking dire consequences for the hundreds of millions of people who depend on the sea. [...]"
Source: The Guardian
Declining oxygen in the global ocean and coastal waters
"Oxygen is fundamental to life. Not only is it essential for the survival of individual animals, but it regulates global cycles of major nutrients and carbon. The oxygen content of the open ocean and coastal waters has been declining for at least the past half-century, largely because of human activities that have increased global temperatures and nutrients discharged to coastal waters. [...]"
Authors: Denise Breitburg et al.
Patterns of deoxygenation: sensitivity to natural and anthropogenic drivers
"Observational estimates and numerical models both indicate a significant overall decline in marine oxygen levels over the past few decades. Spatial patterns of oxygen change, however, differ considerably between observed and modelled estimates. Particularly in the tropical thermocline that hosts open-ocean oxygen minimum zones, observations indicate a general oxygen decline, whereas most of the state-of-the-art models simulate increasing oxygen levels. Possible reasons for the apparent model-data discrepancies are examined. [...]"
Source: Philosophical Transactions of the Royal Socie
Authors: Andreas Oschlies et al.
Deep oceans may acidify faster than anticipated due to global warming
"Oceans worldwide are undergoing acidification due to the penetration of anthropogenic CO2 from the atmosphere. The rate of acidification generally diminishes with increasing depth. Yet, slowing down of the thermohaline circulation due to global warming could reduce the pH in the deep oceans, as more organic material would decompose with a longer residence time. [...]"
Source: Nature Climate Change
Authors: Chen-Tung Arthur Chen
Read the full article here.
Function of the High Seas and Anthropogenic Impacts Science Update 2012 - 2017
The Zoological Department of Oxford University has reviewed and synthesised major marine science findings which have been published since Rio+20 in 2012.
The purpose of this synthesis is to determine how our understanding of the ocean at an Earth System level, with a particular focus on the role of the high seas, has changed in the last five years.
"During the last five years scientists have utilised novel technologies and methods to explore new locations and investigate both the fundamental processes of the ocean and the mounting anthropogenic impacts on the marine environment. Studies have highlighted the important functions that the high seas perform for the planet and have often focused on the complexity and interconnected nature of these processes."