Massive seagrass beds in Western Australia’s Shark Bay — a UNESCO World Heritage Site — haven’t recovered much from the devastating heat wave of 2011, according to a new study demonstrating how certain vital ecosystems …
A large international team of researchers has found another troubling indicator of climate change: the Arctic Ocean around the North Pole is getting warmer, and in the process, becoming more like the Atlantic Ocean to its south. Specifically, the eastern Eurasian Basin is now more ice-free and showing mixing of vertical layers of water, a phenomenon common in the Atlantic. Record-breaking loss of sea ice has become a common feature in the Arctic every summer the last 10 years or so. Since 2011, the eastern Eurasian Basin region has been nearly free of ice at the end of every summer.
Changes in the way that ocean temperatures were measured in recent decades made it look like the oceans were getting cooler, but now independent data has confirmed that this so-called ‘hiatus’ in global warming never actually happened. The cause of the apparent hiatus in rising sea-surface temperatures was first identified in 2015 in a paper in the journal Science by scientists at the National Oceanic and Atmospheric Administration (NOAA). The paper proved controversial, but since its publication, several studies have backed up the idea that the hiatus didn’t in fact happen. The apparent hiatus has been linked to poor statistical methods, among other factors.
Mother-of-pearl or nacre (pronounced nay-ker), the lustrous, tough-as-nails biomineral that lines some seashells, has been shown to be a faithful record of ancient ocean temperature. Writing online Thursday, Dec. 15, in the journal Earth and Planetary Science Letters, a team led by University of Wisconsin-Madison physics Professor Pupa Gilbert describes studies of the physical attributes of nacre in modern and fossil shells showing that the biomineral provides an accurate record of temperature as the material is formed, layer upon layer, in a mollusk.
Seaweed-eating fish are becoming increasingly voracious as the ocean warms due to climate change and are responsible for the recent destruction of kelp forests off the NSW north coast near Coffs Harbour, research shows. The study includes an analysis of underwater video, covering a 10-year period between 2002 and 2012, during which the water warmed by 0.6 degrees. “Kelp forests provide vital habitat for hundreds of marine species, including fish, lobster and abalone,” says study first author Dr Adriana Vergés of UNSW and the Sydney Institute of Marine Science.
An ice sheet in West Antarctica is breaking from the inside out. The significant new findings published yesterday in Geophysical Research Letters show that the ocean is melting the interior of the Pine Island Glacier, which is about the size of Texas. The crack seems to be accelerating, said Ian Howat, associate professor of earth sciences at Ohio State University and the study’s lead author. The findings are the first confirmation of something glaciologists have long suspected was happening, he said.
The sun set on the North Pole more than a month ago, not to rise again until spring. Usually that serves as a cue for sea ice to spread its frozen tentacles across the Arctic Ocean. But in the depths of the polar night, a strange thing started to happen in mid-October. Sea ice growth slowed to a crawl and even started shrinking for a bit. Intense warmth in both the air and oceans is driving the mini-meltdown at a time when Arctic sea ice should be rapidly growing. This follows last winter, when temperatures saw a huge December spike.
A new multi-institutional study of the so-called global warming “hiatus” phenomenon — the possible temporary slowdown of the global mean surface temperature (GMST) trend said to have occurred from 1998 to 2013 — concludes the hiatus simply represents a redistribution of energy within Earth system, which includes the land, atmosphere and the ocean.
In a ghost town of dead coral off a remote Pacific island, scientists have found a little more life. In excursions a year ago and then last April, scientists examined the normally-stunning coral reefs around the island of Kiritimati and pronounced it mostly a boneyard of dead coral. About 85 per cent of the coral was dead, 10 per cent was sick and bleached but still technically alive, and only 5 per cent was doing okay. The same scientists returned this month and found that 6 to 7 per cent of the coral is alive and not bleached, says Julia Baum, coral reef scientist from the University of Victoria, in Canada.
Coral reefs around the globe already are facing unprecedented damage because of warmer and more acidic oceans. It’s hardly a problem affecting just the marine life that depends on them or deep-sea divers who visit them.
It’s boom time for large whales in the Arctic – an unexpected benefit of the unprecedented sea ice reduction seen in the region over the past 30 years.
A new study has found for the first time that ocean warming is the primary cause of retreat of glaciers on the western Antarctic Peninsula. The Peninsula is one of the largest current contributors to sea-level rise and this new finding will enable researchers to make better predictions of ice loss from this region.