Current AGU Journal Covers

Current covers of AGU Journals.  For older covers, see the archives of each journal.  High resolution images are available in the issue information PDF of each issue.

in GBC

In Crusius et al., (top left) Expanded map of sampling region. The map at right shows the sampling stations (green circles) on the shelf/slope transect extending seaward from near the mouth of the Copper River (AK) (Station 1) to beyond the shelf break (Station 5).

Surface water currents are denoted with blue arrows and include the Alaska Coastal Current (ACC) along the shelf, the Alaska Current, and Alaskan Stream [modified from Lippiatt et al., 2011]. The thin blue contour line is the 500 m depth contour and gives the approximate position of the shelf break, while the white contour is the 100 m depth contour. Station locations and depth contours are superimposed on a MODIS true-color image from 9 April 2010,
the same day Stations 4 and 5 were sampled. True-color image generated using HDFlook.

Early Results: Juno at Jupiter in GRL

Juno’s MicroWave Radiometer (MWR) passively observes beneath Jupiter’s cloud tops. This artist’s conception shows real data from the 6 MWR channels, arranged by wavelength.

Equatorial plasma bubble generation/inhibition during 2015 St. Patrick's Day storm in Space Weather

Ionospheric response during the storm over Taiwan and Indian longitudes on 17
March 2015. The data assimilation results over (left column) Taiwan and (right column) Indian longitudes are plotted, showing (
first row) electron
density (Ne), (second row) zonal electric field (
E
φ
), and (third row) meridional wind (
v
), respectively, at 1900 LT. The altitude gradient of flux tube
integrated electron density (1/N[dN/dh]) at (dotted) 1900 LT and (dashed) 1930 LT is overplotted on the electron density contou
rs in Figure 4 (first row)

Evolution Model for the Absheron Mud Volcano: From In Situ Observations to Numerical Modeling in JGR: Earth Surface

High-resolution bathymetric map of the area of the Absheron
mud volcano acquired with a multi-beam echo sounder.

Fiber-Optic Network Observations of Earthquake Wavefields in GRL

The cover figure shows examples of local and regional seismic events observed using surface fiber-optic cables and distributed acoustic sensing (DAS).
Left: installation photographs from three sites with fiber optic cables including Richmond, CA (top), Fairbanks, AK (middle), and Stanford, CA (bottom). Right: a small catalog of seismic events observed using these surface DAS cables from 5 to 500
km epicentral distance. Events are color-coded to the site of observations.

Dry deposition of particles to canopies—A look back and the road forward in JGR: Atmospheres

Comparison of the nontransport processes that affect PM

2.5
concentration in the
lowest 100 m of the atmosphere as estimated from a regional-scale air quality model simulation for June 2013. The area over which the results
(averages) apply is about 500 km × 500 km, as indicated by the inner square of the CAMx domain illustration inset. The time scale markings indicate
noon (EST). The dry deposition estimates result from an assumption about the deposition velocity that is a focus of the current presentation. The time
period selected for this illustration was free of rainfall.

Building the Pamir-Tibetan Plateau—Crustal stacking, extensional collapse, and lateral extrusion in the Central Pamir: 1. Geometry and kinematics in Tectonics

 In Rutte et al. [DOI: 10.1002/2016TC004293], image shows (a–d) Panoramic views of the Muskol dome. Distortion increases toward the image edges. Figures 4a and 4b

are along section A in Figure 8. Thrusts and north vergent, recumbent, isoclinal folds in Figure 4d are in left part of Figure 4c. (e–h) Fault scarps in colluvial and alluvial deposits
and range front normal faults along the active Sarez-Karakul graben system

An Optimally Stable and Accurate Second-Order SSP Runge-Kutta IMEX Scheme for Atmospheric Applications in JAMES

 Rokhzad et al studied optimization of dissipation and dispersion errors for two-frequency system of equations using IMEX Runge-Kutta schemes. They found A-stability property to be more useful than L-stability property, more specifically for stiff limits, since A-stability allows to increase the range of stability (first row) and decrease the phase errors (second and third rows), which are related to larger stable time step size and more accurate solutions respectively.

Modulations of Saturn's UV Auroral Oval Location by Planetary Period Oscillations in JGR: Space Physics

Image shows an ultraviolet imaging spectrograph (UVIS) image of Saturn’s northern
hemisphere from 2008 DOY 239 at 03:37. The authors find systematic changes to the auroral oval location that correspond to planetary period oscillations.

Relationship Between the Orientation of Maximum Permeability and Intermediate Principal Stress in Fractured Rocks in WRR

Image shows surfaces, apertures, and flow field for isotropic and anisotropic fractures. (a) top row: Isotropic fracture. Bottom row: Anisotropic fracture. From left to right: The composite surface, h, the rigid aperture field,
a, the mechanical aperture field under elastic compression, am, and the contact stress,
σ, and flow velocity field. (b) The aperture distribution of and afor both cases and (c) the power law distributed contact cluster size.

Coupled topographic and vegetation patterns in coastal dunes: Remote sensing observations and ecomorphodynamic implications in JGR: Biogeosciences

In Yousefi Lalimi et al.(DOI: 10.1002/2016JG003540), the image shows (a and d) DTM, (b and e) LAI, and (c and f) NDVI for site 1 (Figures 4a–4c) and site 2 (Figures 4d–4f). The first crest-line (closest to the shoreline) and the shoreline are shown in each map.

Air-sea fluxes for Hurricane Patricia (2015): Comparison with supertyphoon Haiyan (2013) and under different ENSO conditions in JGR: Oceans

Hurricane Patricia (Oct., 2015) and Supertyphoon Haiyan (Nov. 2013) are the 2 ‘Champion Tropical Cyclones in the recorded human history. These 2 cyclones can be called category ‘6’ super cyclones, because both reached an astonishing peak intensity, far exceeding the existing highest category of 5 in the tropical cyclone scale. This illustration shows the approach of these 2 super cyclones’ to the Philippines and Mexico, i.e. the 2 sides of the Pacific Ocean. These 2 champion cyclones are compared and reasons are explore on their extra-ordinary intensifications. The tropical cyclone trajectories and intensity are obtained from the best track archives of National Hurricane Centers (NHC; http://ftp.nhc.noaa.gov/atcf/archive/) and the US Joint Typhoon Warning Centre (JTWC; https://metoc.ndbc.noaa.gov/web/guest/jtwc/best_tracks/). The visible images are provided from the Rapid Response imagery from the Land, Atmosphere Near real-time Capability for EOS (LANCE) system operated by the NASA/GSFC/Earth Observing System Data and Information System (EOSDIS)(https://lance.modaps.eosdis.nasa.gov/cgibin/imagery/gallery.cgi). The image of Hurricane Patricia over Mexico was taken from the MODIS instrument aboard NASAs Terra satellite on Oct. 23, 2015 at 17:30 UTC/1:30 p.m. EDT. The image of supertyphoon Haiyan approaching the Philippines was taken from the MODIS instrument aboard NASAs Aqua satellite on Nov. 7, 2013 at 04:25 UTC/Nov. 6 at 11:25 p.m. EDT. Thanks to NASA/EOSDIS (https://lance.modaps.eosdis.nasa.gov/cgi-bin/imagery/gallery.cgi) for providing the visible images from Terra and Aqua/MODIS, and to NHC (http://ftp.nhc.noaa.gov/atcf/archive/), JTWC(https://metoc.ndbc.noaa.gov/web/guest/jtwc/best_tracks/) for TCs best track and intensity data.

Structure and dynamics of a subglacial discharge plume in a Greenlandic fjord in JGR: Oceans

photograph of the JetYak as it approaches the glacier face taken from a helicopter. Inserts

show a picture of the JetYak and of the boat from which it was controlled.

Investigation on the Multiparameter of Hydrate‐Bearing Sands Using Nano‐Focus X‐Ray Computed Tomography in JGR: Solid Earth

(a) methane bubbles showed in the pores with green color; (b) free water showed in the
pores with red color; (c) methane hydrate showed in the pores with yellow color; and (d) the continuous pore channels of hydrat
e‐bearing porous
media with 14% hydrate saturation.

Primary Production and Calcification Rates of Algae‐Dominated Reef Flat and Seagrass Communities in JGR: Biogeosciences

Field survey sites at (a) Heron Reef, southern Great Barrier Reef, Australia, and (b) Saipan
Lagoon, Commonwealth of the Northern Mariana Islands, where flow respirometry drifts were conducted. One site was surveyed in Shark Bay on the
east side of Heron Island. Two sites were surveyed in Saipan Lagoon off of Pau Pau Beach, an algae‐dominated, coral reef flat, and San Roque, a seagrass
community. The black lines denote flow respirometry tracks, the yellow point is where current meter and Wetlabs PAR sensor were placed, and the
yellow arrow is general current direction. WorldView 2 imagery provided by the Remote Sensing Research Centre at the University of Queensland and
CNMI Bureau of Environmental and Coastal Quality.

Ceres's obliquity history and its implications for the permanently shadowed regions in GRL

Ceres has plenty of permanently shadowed regions (mapped in blue) at the present day when its obliquity is small. However, due to obliquity changes in the past, only few permanent shadows remain.

Holocene Event Record of Aysén Fjord (Chilean Patagonia): An Interplay of Volcanic Eruptions and Crustal and Megathrust Earthquakes in JGR: Solid Earth

 Offshore sedimentary trace of the Quitralco Fault, showing vertical stratigraphic offset.
(a) Multibeam bathymetry map where the gray shading of the fault trace represents the offset at the seafloor, which is consistent with “surface” rupture of the bedrock below the fjord’s sedimentary infill following the Mw6.2 earthquake’s (epicenter indicated by red star) moment tensor (Legrand et al., 2011): Black, no vertical offset, where fault trace is parallel to along-fault movement; white, largest offset, at an angle with movement along the fault. Location of deltaic sediments dated in Vargas et al. (2013) is indicated (white dot), (b) zoom from part of TOPAS profile 024 (dashed line, where offset is maximal) that shows the seismic expression of the fault, with indication of fault offset values for each stratigraphic level. The shaded area indicates the megaturbidite that levels vertical offset at SL-F.

Further evidence for early lunar magnetism from troctolite 76535 in JGR: Planets

In Garrick-Bethell et al. [DOI: 10.1002/2016JE005154], photographs of two opposite faces of 76535, 153 are shown. Lines indicate the approximate

sizes and locations of subsamples 1, 2, and 3.

The Incorporation of Field Portable Instrumentation Into Human Planetary Surface Exploration in Earth and Space Science

Image shows (a) a typical setup of multispectral frame imager and external calibration
targets in the field. (b) Scanning hyperspectral imager (image credit: Spectrum Photonics, Inc.). (c–d) Example data product fr
om infrared spectral
imaging. The scene is at Kilauea field site seen in visible light (c) and false color infrared (d), derived from the multispect
ral frame imager. Compositional
and/or textural variations in the scene are captured. 

The export and fate of organic matter in the ocean: New constraints from combining satellite and oceanographic tracer observations in GBC

In DeVries and Weber, DeVries and Weber combined satellite and oceanographic tracer data to estimate the flux of sinking organic carbon out of the ocean‘s euphotic zone, and the efficiency with which the carbon is transferred to the deeper ocean.

Their findings demonstrate that the highest rates of organic carbon export are found in upwelling regions along coasts, near the equator, and in the sub-polar oceans (light blue to red colors). This carbon is transferred into the deeper ocean most efficiently in the high latitudes and near oxygen minimum zones, where cold temperatures and reduced oxygen concentrations lead to slow respiration rates.