State of the Oceans — Log 90

Jul 11

YOUR WEEKLY BRIEFING FROM PARLEY

This image by Cinzia Osele Bismarck / Coral Reef Image Bank. Header image by Yen-Yi Lee / Coral Reef Image Bank.

GLOBAL HEATING

By 2100, 60% of all fish species will be unable to survive in their current ranges if climate warming reaches a worst-case scenario of 4-5C. The finding comes from a study that assessed 700 fish species’ ability to adapt to different warming-scenarios. Specifically, the researchers examined reproduction and the risks young fish face from reduced oxygen-intake – a result of ocean heating. The experts warn that losing just 10% of fish species – a very realistic prediction – could have consequences for entire ecosystems: “Some tropical fish are already living at their uppermost tolerance. Humankind is pushing the planet outside of a comfortable temperature range and we are starting to lose suitable habitat.”

The study comes as new projections from the U.N.’s World Meteorological Society show increasing odds the world could cross a critical climate threshold by 2024. The new forecasts show there is a slight chance the annual global temperature will be 1.5 degrees C warmer than preindustrial levels for the first time within one of the next five years. That figure is important because it's a target countries agreed to in the 2015 Paris climate agreement. Keeping annual global temperatures from rising more than 1.5 degrees will greatly reduce the risks and impacts of climate change. The world has already warmed by more than 1ºC since the Industrial Revolution, and atmospheric CO2 is nearing the highest it’s been in 15 million years.

INNOVATION

To address climate change, researchers suggest spreading rock dust across the world’s farmlands – a simple technique that could store billions of tons of CO2 from the atmosphere every year, according to a new paper in Nature. The theory relies on a basic chemical reaction: as rock particles break down, they increase soil’s ability to capture CO2 from the air. If adopted on half of all farms, the approach could absorb two billion tons of CO2 annually, equal to Japan and Germany’s combined emissions. “Enhanced Rock Weathering,” as it’s called, might sound complicated, but most farmers already spread some form of rock dust to make soils less acidic – and the material is widely available. While emission reductions remain the priority, scientists agree that removing CO2 from the atmosphere is also critical.

MARINE CONSERVATION

Protecting marine habitat is critical for wildlife, and it’s also a natural solution in the fight against climate change. Seagrass meadows, for example, can store carbon from the atmosphere 30 times faster than forests on land. Yet around the world these ecosystems are threatened by ocean warming, pollution and coastal development. New research suggests that over 160,000 hectares of Australia’s seagrass meadows have disappeared since the 1950s. In terms of emissions, that loss is equal to putting more than five million cars on the road every year. As one researcher – a PhD student – explains: “This study serves as a stark reminder of how important these environments are. Without seagrass acting as a buffer, the energy from the ocean releases carbon by moving the seabed sand around.”

MICROPLASTICS

For the first time, researchers are attempting to estimate the number of microplastics in Atlantic Canada. The three-year, government-funded study has already identified fishing gear as a major source of microplastics in Nova Scotia and Newfoundland. The study has also found microplastics in every water sample so far, a result that is surprising researchers: “It definitely was even more than we thought we would find. Microplastics end up ubiquitously across marine environments.” The study is one of a few strides Canada has taken to combat plastic pollution. Multiple provinces are collaborating with the federal government to create a zero plastic waste strategy while a separate coalition has launched twenty projects that range from addressing lost fishing gear to building ropeless traps.

OCEAN HEALTH

According to new research, a common Indonesian sea sponge produces a chemical that could help fight cancer. Specifically, bacteria within the sponge create a substance called manzamine A, which has been shown to counter cervical cancer cells in laboratory settings. Unlike most cancer treatments, this chemical has the potential to suppress tumor growth without harming healthy cells and causing toxic side-effects. While manzamine A’s effects in humans remain unknown, the study’s authors believe these sponges – which filter seawater – could also benefit economies and environments: “It would be a promising development tool to put sponge culture facilities where there’s high nutrient loads to improve water quality and build a business around the manufacture of the drug.”