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As one of the largest heat reservoirs in the climate system, the global ocean absorbs more than 90% of the excess energy from ongoing anthropogenic warming. In the last century, the greatest warming in the ocean has occurred in the upper 500 m, with relatively weak warming in the deep ocean, corresponding to a small ocean heat storage efficiency of ~0.1.

Nestled in the Uinta Mountains of northern Utah, a series of pristine lakes are facing a new threat—humans. Geography professor and chair Katrina Moser led a team of researchers in the region this summer to better understand how human activity, like agriculture and warming temperatures because of climate change, is leading to dramatic changes in a water system far from populous areas.

The Copernicus Sentinel-2 mission has snapped a souvenir of the Burning Man festival in the Black Rock desert in Nevada.

This study explores the b-value variations prior to M ≥ 6.0 earthquakes in Taiwan, examining their potential as earthquake precursors. Focusing on the 2018 Hualien earthquake and others between 1999 and 2021, we ...

Abstract

Real Time Precise Point Timing (RT-PPT) receivers can achieve sub-nanosecond accuracy through precise clock offset estimation and receiver clock discipline. However, when satellite signals are lost, the receiver clock drifts, causing timing errors due to clock noise and environmental factors. Strict autonomous holdover is therefore essential for high-precision timing receivers. This paper proposes a time holdover method based on online clock modelling. At the timing stage, the frequency bias compared to the time reference is estimated and eliminated by the closed control loop. Meanwhile, the recursive least square algorithm is used to estimate the parameters of the clock temperature and ageing effects online. In the event of signal interruption, the initial frequency bias is reduced by one-step prediction, while the clock offset caused by temperature and ageing is compensated for using the estimated parameters. To verify the validity of the method, real experiments were carried out using an RT-PPT receiver with different types of oscillators. The results show that with the method proposed in this paper, we can achieve holdover accuracy better than 1ns in 1h using a rubidium clock after correcting for the initial frequency bias, with an improvement of more than 67% over the free-running clock. And the holdover accuracy of the receiver using an OCXO after correcting for temperature and ageing is better than 1us in 24h, with a performance improvement of more than 70% over the free-running clock.

Nature Geoscience, Published online: 20 September 2024; doi:10.1038/s41561-024-01546-7

Reply to: NO2 satellite retrievals biased by absorption in water

Nature Geoscience, Published online: 20 September 2024; doi:10.1038/s41561-024-01545-8

NO2 satellite retrievals biased by absorption in water

Abstract

Based on decades of single-spacecraft measurements near 1 au as well as data from heliospheric and planetary missions, multi-spacecraft simultaneous measurements in the inner heliosphere on separations of 0.05–0.2 au are required to close existing gaps in our knowledge of solar wind structures, transients, and energetic particles, especially coronal mass ejections (CMEs), stream interaction regions (SIRs), high speed solar wind streams (HSS), and energetic storm particle (ESP) events. The Mission to Investigate Interplanetary Structures and Transients (MIIST) is a concept for a small multi-spacecraft mission to explore the near-Earth heliosphere on these critical scales. It is designed to advance two goals: (a) to determine the spatiotemporal variations and the variability of solar wind structures, transients, and energetic particle fluxes in near-Earth interplanetary (IP) space, and (b) to advance our fundamental knowledge necessary to improve space weather forecasting from in situ data. We present the scientific rationale for this proposed mission, the science requirements, payload, implementation, and concept of mission operation that address a key gap in our knowledge of IP structures and transients within the cost, launch, and schedule limitations of the NASA Heliophysics Small Explorers program.

The tiniest and oldest creatures on—and in—Earth have a huge role in achieving a sustainable future for the planet, an international team of scientists, including faculty researchers from The Ohio State University, asserts in a new Cell article published today.

Just a month after its launch, ESA's Arctic Weather Satellite has already delivered its first images, notably capturing Storm Boris, which has been wreaking havoc across central Europe.

There is a high risk of increased metal emissions from coastal areas in the future. In a new model published in Limnology and Oceanography Letters, researchers from the University of Gothenburg show that climate change and overpopulation can flush out heavy metals that have long been buried in sediments, and where on Earth the risk of this is greatest.

A new study co-led by the Smithsonian and the University of Arizona offers the most detailed glimpse yet of how Earth's surface temperature has changed over the past 485 million years.

Ice may look safe for a game of pick-up hockey on the lake, but as a new study out of York University found, looks can be deceiving. Warming winters are not only affecting ice thickness and timing—when a lake freezes and thaws—but also quality, making it potentially unstable and unsafe.

The summer of 2024 was the hottest on record and, unfortunately, this came as no surprise. Summers have been getting hotter and drier around the world, including in the Northern Hemisphere, leading to intense droughts and heat waves in North America and Europe and posing serious risks to society such as wildfires, crop failures and health hazards.

Some of the most dramatic climatic events in our planet's history are "Snowball Earth" events that happened hundreds of millions of years ago, when almost the entire planet was encased in ice up to 0.6 miles (1 kilometer) thick.

The Amazon, often called the "lungs of the planet," is the world's largest tropical forest, playing a crucial role in the global climate system due to its vast carbon storage. While it is typically warm and humid all year round, continued climate change poses the threat of more frequent and severe droughts and heat extremes.

Climate change is forcing people to adapt to changing environmental conditions. But what really makes the difference is how they do it. The recently published "Hamburg Climate Futures Outlook 2024" by 73 authors shows that, in the long run, only sustainable adaptation can succeed. This global assessment by University of Hamburg's Cluster of Excellence Climate, Climatic Change, and Society (CLICCS) also provides practical recommendations.

Indiana University researchers have uncovered key insights into the dangerous phenomenon of "river avulsion," offering a way to predict when and where rivers may suddenly and dramatically change course. Published in Nature, this breakthrough study sheds light on a process that has shaped human history through devastating floods and continues to threaten millions of people worldwide.

Imagine the conductor of a vast orchestra stood not at the front, but in the middle of all the musicians, dictating how they work together and the music they produce. The musicians are not stationary; they move past each other and interact, but all the while still controlled by the unmoving conductor.

The Arctic frequently experiences temperatures that support the formation of mixed-phase clouds that contain supercooled liquid droplets and ice crystals. The composition of such clouds plays a crucial role in the region's energy balance and climate system. Clouds with more liquid last longer and reflect more sunlight than those with more ice crystals.