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Ocean tide size linked to supercontinent cycle

Daily tides are driven primarily by Earth’s rotation and the gravitational force of the moon on oceans. However, in a new study in Geophysical Research Letters, researchers suggest that tidal magnitudes are also influenced, on longer timescales, by the size and shape of the ocean basins, and are therefore driven by plate tectonics.

07 Sep 2018

Sea-level rise could cut off wastewater service to millions in U.S.

Scientists report in a recent study that with just 30 centimeters of sea-level rise, roughly 4 million people in the U.S. could lose access to municipal wastewater services — services that allow three-quarters of America to run the tap and flush the toilet. And with even higher seas, the number goes up.

21 Jun 2018

When more humidity means less water

Scientists have long assumed that temperature is the main control on melting of winter snowpacks across the mountainous western United States. In a recent study, however, scientists suggest that regional humidity may have a larger impact than temperature.

16 May 2018

El Nino "flavors" affect California rainfall

Twenty years ago, the 1997–98 El Niño surpassed the 1982–83 event to become the strongest El Niño ever recorded, contributing to famine and drought in Southeast Asia, devastating floods in Southern California, and other natural disasters. By many metrics, the 2015–16 El Niño bested both to claim the title of the strongest El Niño on record. This most recent event, nicknamed the “Godzilla El Niño,” did contribute to extreme weather in parts of the world, including disastrous fires in Indonesia and the longest, global coral-bleaching event on record. However, it did not have the anticipated effect on California, which, at the time, was in the midst of a severe multi-year drought. In a recent study, researchers suggest the 2015–16 El Niño was the wrong “flavor” to bring heavy precipitation to the state.

13 May 2018

Earth's "hum" heard at ocean bottom

Lapping waves or crashing surf may come to mind for most people when they imagine the sounds of the ocean. But the ocean has other voices as well, including one produced by interactions of waves with the seafloor along the continental slope. Unlike waves on the shoreline, this steady, low sound, or “hum,” is inaudible to the human ear and has even proven difficult to detect in recordings made by ocean bottom seismometers (OBS). But in a new study in Geophysical Research Letters, researchers analyzing OBS data have now clearly identified the hum for the first time, which may allow it to be used to develop a better picture of Earth’s interior structure.

04 Apr 2018

LIP split by South Atlantic breakup was sourced from deep

Massive volumes of rock called large igneous provinces (LIPs) have formed many times throughout Earth’s history, fed by some of the planet’s mightiest volcanic events. The volcanic eruptions, sometimes lasting millions of years and pouring hundreds of thousands of cubic kilometers of lava onto the surface, have influenced continental breakups, past climate change and mass extinction events. For everything that’s known about LIPs, however, many questions about them remain, including how far below the surface the erupted magma originate. In a recent study, researchers report that the origins of the Paraná-Etendeka LIP likely lay deep in Earth’s interior.

16 Mar 2018

No river meant no floods for ancient Indus settlements

Large Middle Eastern rivers like the Nile, Tigris, Euphrates and Tiber were critical for the development of early urban societies in Egypt, Mesopotamia and Ancient Rome. And researchers have long thought that the rise, and eventual decline, of cities in the ancient Indus Civilization, which spread across about 1 million square kilometers of what’s now northwestern India and Pakistan from roughly 4,600 to 3,900 years ago, also depended on major rivers, namely those emerging from the Himalayas. But a new study looking at river sediments from the time of the civilization and earlier suggests that wasn’t the case for every ancient Indus city; some may have benefited from being farther away from large rivers and their periodic floods.

23 Jan 2018

Mediterranean drawdown may have caused burst of volcanism

Between 5 million and 6 million years ago, during an event known as the Messinian Salinity Crisis (MSC), large amounts of seawater evaporated from the Mediterranean Sea leaving massive salt deposits in the basin. How much the sea surface dropped during the MSC is debated, but in a new study in Nature Geoscience, researchers suggest that a large, kilometer-scale drawdown of the Mediterranean Sea may explain not just the thick salt deposits but also a pulse of magmatic activity around the region that occurred at the same time as the MSC.

17 Jan 2018

Driftwood reveals ancient Arctic currents and sea-ice levels

Arctic driftwood up to 12,000 years old is giving scientists a better understanding of how ocean currents and sea ice in the far north have changed through the Holocene. In a new study, published in the Journal of Geophysical Research: Oceans, scientists at the University of Oxford in England studied more than 900 pieces of driftwood collected from Arctic shorelines since the 1950s to investigate how shifting Arctic Ocean currents help melt or fortify sea ice.

28 Dec 2017

Opportunist organisms rafted across the Pacific on plastic

Since World War II, fiberglass and plastic — which are stronger, lighter and require less maintenance than wood — have become the materials of choice for coastal infrastructure like docks. An unforeseen consequence of this transition, however, is that when structures built from these durable materials break free from their moorings and drift out to sea, they can serve as resilient rafts for opportunistic organisms. 

21 Nov 2017

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