I. Climate Change

1.Reducing Errors in Satellite-Derived Arctic Sea Ice Thicknesses

Salty snow throws off satellite-based estimates of Arctic sea ice thickness by up to 25%. A new method seeks to fix that.

https://eos.org/research-spotlights/reducing-errors-in-satellite-derived-arctic-sea-ice-thicknesses

2.Ocean Circulation, Carbon Cycling During the Last Deglaciation

Past Global Changes (PAGES) OC3 Working Group second workshop on Ocean Circulation and Carbon Cycling during Last Deglaciation: Regional Synthesis of Carbon Isotopes Data; Corvallis, Oregon, 27–29 June 2017

https://eos.org/meeting-reports/ocean-circulation-carbon-cycling-during-the-last-deglaciation

II. Geochemistry, Mineralogy, Volcanology

1.Exploring the Restless Floor of Yellowstone Lake

Yellowstone Lake, far from any ocean, hosts underwater hot springs similar to those on mid-ocean ridges. A research team is investigating the processes that drive the lake’s hydrothermal systems.

https://eos.org/project-updates/exploring-the-restless-floor-of-yellowstone-lake

2.“North Pacific Nutrient Leakage” During Glacials

Carbon isotope data suggest an alternative source of nutrients to the Eastern Equatorial Pacific during glacial periods.

https://eos.org/editor-highlights/north-pacific-nutrient-leakage-during-glacials

III. Hydrology, Cryosphere & Earth Surface

1.Ice Caves atop a Volcano Give Taste of Otherworldly Science

Researchers brave perils and tumbling trash to probe glacial caves on Mount Rainier, improving their understanding of its extraordinary environment and helping to advance space exploration.

https://eos.org/articles/ice-caves-atop-a-volcano-give-taste-of-otherworldly-science

IV. Biogeosciences

1.Sandy Beaches Are Hotbeds of Biochemical Activity

A new study explores the role of wet sand in coastal ecology.

https://eos.org/research-spotlights/sandy-beaches-are-hotbeds-of-biochemical-activity

V. Geology & Geophysics

1.AGU Editor Picks for 2017 Fall Meeting, Part II

AGU's journal editors give their recommendations for some of the most interesting paper, panel, and poster sessions coming up at this year’s meeting.

https://eos.org/editors-vox/agu-editor-picks-for-2017-fall-meeting-part-ii

2.AGU Editor Picks for 2017 Fall Meeting, Part I

AGU's journal editors give their recommendations for some of the most interesting paper, panel, and poster sessions coming up at this year’s meeting.

https://eos.org/editors-vox/agu-editor-picks-for-2017-fall-meeting-part-i

3.AGU College of Fellows Announces Program Plans

A new group that represents the American Geophysical Union’s Fellows kicks off its programs through 2018 with a town hall at the 2017 AGU Fall Meeting about scientific publishing.

https://eos.org/agu-news/agu-college-of-fellows-announces-program-plans

4.Introducing the New Editor in Chief forG-Cubed

Find out who is taking over atGeochemistry, Geophysics, Geosystems, AGU’s premier interdisciplinary journal, and his vision for the coming years.

https://eos.org/editors-vox/introducing-the-new-editor-in-chief-for-g-cubed

VI. Geophysical Research Letters

1. Enhanced Chlorophyll Concentrations Induced by Kuroshio Intrusion Fronts in the Northern South China Sea

New evidences were provided that Kuroshio intrusion in winter is able to increase phytoplankton growth in the open ocean of the northern South China Sea (SCS) based on multiple data sources. Strong fronts due to Kuroshio intrusion and interactions with the SCS water are associated with intense upwelling, supplying high nutrients from the subsurface SCS water and increasing phytoplankton productivity in the frontal region. High chlorophyll is more dynamically related to these fronts than to the alongshore wind, wind stress curl, and eddy kinetic energy on interannual time scale. Further examinations suggest that fronts associated with Kuroshio intrusion into the SCS are linked with large-scale climate variability. During El Niño years, stronger Kuroshio intrusion results in stronger fronts that generate intensified local upwelling and enhanced Luzon winter blooms.

http://onlinelibrary.wiley.com/doi/10.1002/2017GL075336/full

2. Increasing Coupling Between NPGO and PDO Leads to Prolonged Marine Heatwaves in the Northeast Pacific

The marine heatwave of 2014/2015 in the Northeast Pacific caused significant impacts on marine ecosystems and fisheries. While several studies suggest that land and marine heatwaves may intensify under climate change, less is known about the prolonged multiyear nature (~2 years) of the Northeast Pacific events. Examination of reanalysis products and a 30-member climate model ensemble confirms that prolonged multiyear marine heatwaves are linked to the dynamics of the two dominant modes of winter sea surface temperature variability in the North Pacific, the Pacific Decadal Oscillation (PDO), and the North Pacific Gyre Oscillation (NPGO). Specifically, we find a significant correlation between winter warm NPGO anomalies and the following winter PDO arising from extratropical/tropical teleconnections. In the model projections for 2100 under the RCP8.5 scenario, this NPGO/PDO 1 year lag correlation exhibits a significant positive trend (~35%) that favors more prolonged multiyear warm events (>1°C) with larger spatial coverage (~18%) and higher maximum amplitude (~0.5°C for events >2°C) over the Northeast Pacific.

http://onlinelibrary.wiley.com/doi/10.1002/2017GL075930/full

3. Heat Flux Distribution of Antarctica Unveiled

Antarctica is the largest reservoir of ice on Earth. Understanding its ice sheet dynamics is crucial to unraveling past global climate change and making robust climatic and sea level predictions. Of the basic parameters that shape and control ice flow, the most poorly known is geothermal heat flux. Direct observations of heat flux are difficult to obtain in Antarctica, and until now continent-wide heat flux maps have only been derived from low-resolution satellite magnetic and seismological data. We present a high-resolution heat flux map and associated uncertainty derived from spectral analysis of the most advanced continental compilation of airborne magnetic data. Small-scale spatial variability and features consistent with known geology are better reproduced than in previous models, between 36% and 50%. Our high-resolution heat flux map and its uncertainty distribution provide an important new boundary condition to be used in studies on future subglacial hydrology, ice sheet dynamics, and sea level change.

http://onlinelibrary.wiley.com/doi/10.1002/2017GL075609/full

4. Strong Relations Between ENSO and the Arctic Oscillation in the North American Multimodel Ensemble

Arctic Oscillation (AO) variability impacts climate anomalies over the middle to high latitudes of the Northern Hemisphere. Recently, state-of-the-art climate prediction models have proved capable of skillfully predicting the AO during the winter, revealing a previously unrealized source of climate predictability. Hindcasts from the North American Multimodel Ensemble (NMME) show that the seasonal, ensemble mean 200 hPa AO index is skillfully predicted up to 7 months in advance and that this skill, especially at longer leads, is coincident with previously unknown and strong relations (r> 0.9) with the El Niño–Southern Oscillation (ENSO). The NMME is a seasonal prediction system that comprises eight models and up to 100 members with forecasts out to 12 months. Observed ENSO-AO correlations are within the spread of the NMME member correlations, but the majority of member correlations are stronger than observed, consistent with too high predictability in the model, or overconfidence.

http://onlinelibrary.wiley.com/doi/10.1002/2017GL074854/full

5. Titan's Topography and Shape at the End of the Cassini Mission

With the conclusion of the Cassini mission, we present an updated topographic map of Titan, including all the available altimetry, SARtopo, and stereophotogrammetry topographic data sets available from the mission. We use radial basis functions to interpolate the sparse data set, which covers only ∼9% of Titan's global area. The most notable updates to the topography include higher coverage of the poles of Titan, improved fits to the global shape, and a finer resolution of the global interpolation. We also present a statistical analysis of the error in the derived products and perform a global minimization on a profile-by-profile basis to account for observed biases in the input data set. We find a greater flattening of Titan than measured, additional topographic rises in Titan's southern hemisphere and better constrain the possible locations of past and present liquids on Titan's surface.

http://onlinelibrary.wiley.com/doi/10.1002/2017GL075518/full

VII. AGU Blogs

1.Global Glacier Change Bulletin-Many Glaciers Same Story

The World Glacier Monitoring Service has released the second bulletin ofGlobal Glacier Change. The bulletin provides detailed global and regional information on alpine glaciers particularly for 2014 and 2015. There is data reported from 621 glaciers. The glaciers vary in type and location, yet their response is the same retreat and mass balance loss as a result of the global temperature increases. There are currently 41 reference glaciers with at least 30 consecutive years of detailed field measurement of mass balance.

https://blogs.agu.org/fromaglaciersperspective/2017/12/04/global-glacier-change-bulletin-many-glaciers-story/

2.People and Pyroclastics: Mount Agung at the Confluence of Science and Society

A few days before the status of Mount Agung in East Bali went from Level I (normal) to II (alert). Then quickly elevated again and went to Level III (standby). We weren’t too worried. We had bags packed. Important stuff. Emergency route was planned and we would evacuate to go stay with friends.

https://blogs.agu.org/mountainbeltway/2017/12/01/calderas-culture-mount-agung-confluence-science-society/

3.Delaware Quake May be Africa's “Fault”

This is one of those days that illustrate why broadcast meteorologists must learn all of the Earth science they can. An earthquake struck 10 km east of Dover, Delaware at 4:47 PM EST this Thursday evening.

https://blogs.agu.org/wildwildscience/2017/12/01/delaware-quake-may-africas-fault/