新着論文紹介 AGU・EGU (2013.3/25-3/31)

Geochemistry, Geophysics, Geosystems

Geophysical Research Letters
1. A connection to deep groundwater alters ecosystem carbon fluxes and budgets: example from a Costa Rican rainforest
David P. Genereux, Laura A. Nagy, Christopher L. Osburn and Steven F. Oberbauer
Key Points
Input of regional groundwater can alter ecosystem C concentrations and fluxes
This must be considered for accurate assessment of C budget & source/sink status

2. Regional patterns and proximal causes of the recent snowpack decline in the Rocky Mountains, USA
Gregory T. Pederson, Julio L. Betancourt and Gregory J. McCabe
Key Points
Post-1980s west-wide snowpack declines are driven by spring (Feb-Mar) warming
Low to middle elevation spring snow cover declined by 20%
Recent declines reflect a positive reinforcement of anthropogenic warming

3. Convectively Injected Water Vapor in the North American Summer Lowermost Stratosphere
Michael J. Schwartz, William G. Read, Michelle L. Santee, Nathaniel J. Livesey, Lucien Froidevaux, Alyn Lambert and Gloria L. Manney
Key Points
Aircraft encounter convectively injected water in the N American stratosphere.
Satellite observations show regions/seasons of stratospheric H2O enhancement.
Associated chlorine activation/ozone loss, if present, is at very low levels.

4. A canonical response of precipitation characteristics to Global Warming from CMIP5 models
William K.-M. Lau, H.-T. Wu and K.-M. Kim
Key Points
A canonical rainfall response is found in CMIP-5 models
increased floods and droughts under global warming are connected
Changing rainfall types are more sensitive than total rainfall

5. Extratropical forcing of ENSO
Ghyslaine Boschat, Pascal Terray and Sébastien Masson
Key Points
definition of a new extratropical SST precursor for ENSO predictability
the new precursor offers an independent source of forcing for ENSO
accurate prediction of the amplitude of ENSO events during recent decades

6. Role of mode and intermediate waters in future ocean acidification: analysis of CMIP5 models
L. Resplandy, L. Bopp, J. C. Orr and J. P. Dunne
Key Points
Highest acidification rates are located in mode and intermediate waters (MIW)
MIW combine large carbon uptake with high pH sensitivity to increasing CO2
Low pH in MIW could influence surface pH in upwelling regions

7. The International Bathymetric Chart of the Southern Ocean (IBCSO) Version 1.0 – A new bathymetric compilation covering circum-Antarctic waters
Jan Erik Arndt, Hans Werner Schenke, Martin Jakobsson, Frank O. Nitsche, Gwen Buys, Bruce Goleby, Michele Rebesco, Fernando Bohoyo, Jongkuk Hong, Jenny Black, Rudolf Greku, Gleb Udintsev, Felipe Barrios, Walter Reynoso-Peralta, Morishita Taisei and Rochelle Wigley
Key Points
The first regional bathymetric compilation covering the entire Southern Ocean
A new keystone dataset for Antarctic research
The southern equivalent to IBCAO is now released

8. Surface ozone variability and the jet position: Implications for projecting future air quality
Elizabeth A. Barnes and Arlene M. Fiore
Key Points
Ozone variability is a function of the jet position
Surface ozone variability follows the jet in future climate simulations
Regional ozone-temperature relationships may change in the future

9. Initial-value predictability of Antarctic sea ice in the Community Climate System Model 3
Marika M Holland, Edward Blanchard-Wrigglesworth, Jennifer Kay and Steven Vavrus
Key Points
Antarctic ice predictability on seasonal to inter-annual timescales is assessed
Results suggest significant predictability with an eastward propagating signal
A re-emergence of predictability occurs due to ocean heat content anomalies

10. On the Nature of Meandering of the Springtime Western Boundary Current in the Bay of Bengal
Avijit Gangopadhyay, G.N. Bharat Raj, Ayan H. Chaudhuri, M. T. Babu and Debasis Sengupta
Key Points
WBC in BOB is continuous along the coast and separates at around 18N
The mean WBC has two anticyclones on its offshore side
Interannual variability includes cyclonic eddies on the inshore side of the WBC

11. Changes to Environmental Parameters that Control Tropical Cyclone Genesis under Global Warming
Hiroyuki Murakami, Tim Li and Melinda Peng
Key Points
Environmental variables controlling TC genesis will change under global warming
Predicting TC genesis events will become easier under the warmed environment
TC genesis in the NA resembles more like that in the current WNP climate state
12. Prevalence of strong bottom currents in the greater Agulhas system
Meghan F. Cronin, Tomoki Tozuka, Arne Biastoch, Jonathan V. Durgadoo and Lisa M. Beal
Key Points
Strong bottom currents are prevalent beneath surface jets in the Agulhas system
Surface currents can affect formation of contourites
Noncohesive sediment is lifted more easily by dust storms than by benthic storms

13. Towards resolution-independent dust emissions in global models: Impacts on the seasonal and spatial distribution of dust
D. A. Ridley, C. L. Heald, J. R. Pierce and M. J. Evans
Key Points
Better representation of sub-grid winds reduces resolution dependence of dust
Improved dust seasonality and spatial distribution for coarse resolution models
Sea-salt emissions are found to be relatively independent of model resolution

14. Future European temperature change uncertainties reduced by using land heat flux observations
Annemiek I. Stegehuis, Adriaan J. Teuling, Philippe Ciais, Robert Vautard and Martin Jung
Key Points
European temperature projection uncertainty can be reduced by flux observations
ENSEMBLES temperature projections might be underestimated in parts of Europe

15. Quasi-Stationary North Equatorial Undercurrent Jets across the Tropical North Pacific Ocean
Bo Qiu, Daniel L. Rudnick, Shuiming Chen and Yuji Kashino
Key Points
Three, spatially-coherent, eastward flowing jets beneath westward-flowing NEC.
NEUC jet cores tend to migrate northward when the jets progress eastward.
Jets tend to shoal to lighter density surfaces, as they progress eastward.

JGR Oceans
1. Sea ice thickness estimations from ICESat Altimetry over the Bellingshausen and Amundsen Seas, 2003-2009
Hongjie Xie, Ahmet Emre Tekeli, Stephen F. Ackley, Donghui Yi and H. Jay Zwally
Key Points
evaluation of two different methods for estimating ice thickness from ICESat
empirical equation is preferable than the buoyancy equation for the region
AMSR-E snow depth counting for 95% ice thickness overestimation

2. Mechanisms of aerosol-forced AMOC variability in a state of the art climate model
Matthew B Menary, Christopher D Roberts, Matthew D Palmer, Paul R Halloran, Laura Jackson, Richard A Wood, Wolfgang A Mueller, Daniela Matei and Sang-Ki Lee
Key Points
Aerosols force a long term AMOC strengthening in HadGEM2-ES of ~3Sv
This occurs via atmospheric circulation modulating the NA freshwater budget
Independent ocean models and atmospheric analyses provide qualitative support

3. Detecting Labrador Sea Water formation from space
R. Gelderloos, C. A. Katsman and K. Våge
Key Points
Labrador Sea Water can be detected using satellite altimetry data

4. Seasonal variability of water masses and transport on the Antarctic continental shelf and slope in the southeastern Weddell Sea
Jennifer A. Graham, Karen J. Heywood, Cédric P. Chavanne and Paul R. Holland
Key Points
Wind stress plays a key role determining Antarctic water mass characteristics.
Autumn freshening is strongly influenced by increased along-shore advection.
Antarctic Slope Current peaks during Fall, when wind stress increases.

5. Annual maximum water levels from tide gauges: Contributing factors and geographic patterns
Mark A. Merrifield, Ayesha S. Genz, Christopher P. Kontoes and John J. Marra
Key Points
Mean annual maximum water levels can be specified on a global scale
Tidal and non-tidal contributions to annual maximum water levels are quantified

1. Atlantic Water advection versus sea-ice advances in the eastern Fram Strait during the last 9ka – multiproxy evidence for a two-phase Holocene
Kirstin Werner, Robert F. Spielhagen, Dorothea Bauch, H. Christian Hass and Evgeniya Kandiano
Key Points
Stepwise transition of Holocene to modern situationin eastern Fram Strait
Strong heat flux 9-5 ka, coolings at 8.2., 6.9, 6.1, and 5.2 ka
Neoglacial parallel to flooding of Arctic shelves/modern sea-ice production

2. Erosion and reworking of Pacific sediments near the Eocene-Oligocene boundary
Ted C. Moore Jr.
Key Points
Reworking of Eocene radiolarians occurred as pulses through the late Eocene
Largest reworking pulses at in the E/O boundary interval
Physical erosion and redeposition likely caused by internal wave turbulence

Climate of the past
1. Impact of precipitation intermittency on NAO-temperature signals in proxy records
M. Casado, P. Ortega, V. Masson-Delmotte, C. Risi, D. Swingedouw, V. Daux, D. Genty, F. Maignan, O. Solomina, B. Vinther, N. Viovy, and P. Yiou