Marine heat waves: the devastating impact of climate change on the oceans

Emissions from greenhouse gases They are warming the ocean with profound consequences at all levels, from abundance of organisms to ecosystem processes. The immediate factor is the interaction between anthropogenic warming and natural fluctuations in local temperature. Now a new paper, just published in the Annual Review of Ecology, Evolution and Systematics, highlights the interaction between the two conditions.

These two properties cause atypically warm phenomenasuch as marine heat waves, with increasing frequency and magnitude.

However, the interaction between the continuously warming climate and local temperature peaks is often underestimated. Investigation on climate change They often focus on the global warming trend.

But they also experience organisms in the ocean temperature fluctuations, and that is less explored and therefore less understood. What we’re trying to do is add more reality to ocean change studies by taking into account both the smooth, upward trend in climate warming and the variability of that trend.

The paper proposes a new approach to understanding and modeling marine effects with suggestions for future research.

Coral is an example that illustrates the need for a refreshed look. Even if such an organism is already trying to adapt to the trend of rising temperatures, then it will be hit by a heat wave that will cause a large and sudden increase in temperature.

These peaks tend to cause coral bleaching, which occurs when under metabolic stress they expel the beneficial microscopic algae that live in them and turn white. If the temperature remains high and the algae cannot return to its host coral, the bleached coral will die. Witman noted that heat waves in the Mediterranean caused an increase in coral bleaching and death of corals and sea fans.

Extreme events such as heat waves can alter O damage marine ecosystems in a way that leaves them more vulnerable to both progressive climate change and further temperature fluctuations. AND more realistic model “It can help scientists better identify areas where corals are most likely to die in extreme events, so the organisms that depend on them will be at risk over time.”

In other cases, temperature variability can trigger the opposite response in the affected organism: the ability to acclimatize or adapt to extreme temperatures depending on their frequency and intensity. These responses to variable events are exacerbated and exacerbated by the effects caused by rapid and constant increase ocean temperatures.

He collaborated on the research with Andrew Pershing of the nonprofit Climate Central, who studied biology at Brown; and John Bruno, a professor of biology at the University of North Carolina at Chapel Hill who earned a doctorate in ecology and evolutionary biology from the same university.

The work looked at how organisms and communities adapt or adjust to both smooth trends and variable changes, and then examined the processes that influence the speed at which marine communities adapt to changes in their physical environment, as well as the processes that might make adaptation or acclimatization difficult. The researchers emphasized that all these factors illustrate why it is crucial to consider both types of change when studying marine climate.

If we simply study how organisms respond to a smooth trend, we miss all the variability that drives ecological change. It’s not just the worsening of physiological stress over time; There are also variable events that have their own chain effects.

A global model has been created that shows temperature variability relative to trend and highlights areas where extreme temperatures are likely to be particularly harmful effects. In areas Gulf of Mainhe The Caribbean Sea and Mediterranean Seathere is a high probability of extraordinary warming and ecological surprises.

Key foundation species in these areas, such as seaweed and coral, have already experienced significant changes climate related. These areas in particular deserve exploration to improve our understanding of what will happen in the future, as well as our idea of ​​what we call the new ocean.

*Jon D. Witman professor of biology at Brown University and lead author of the study. The information contained in this press article comes from research entitled “Soft and prickly: The importance of variability in the marine ecology of climate change”, published in Annual Review of Ecology, Evolution and Systematics, which was also authored by Andrew J. Pershing and John F. Bruno. In addition to the press release issued by Brown University.