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James G. Hudson and Stephen Noble

1. Introduction Low stratus clouds that predominate the east sides of oceans provide a majority of the indirect aerosol effect (IAE; Warren et al. 1988 ; Platnick and Twomey 1994 ; Kogan et al. 1996 ), which remains the largest climate uncertainty ( Alley et al. 2007 ). The high radiative temperatures and large albedo contrasts with the underlying ocean provide substantial global cooling that can be increased by the advection and injection of anthropogenic cloud condensation nuclei (CCN

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Ernest Agee, Andrea Orton, and John Rogers

develop the CO 2 sequestration facilities that can substantially curtail the effects of anthropogenic GHG warming. Fig . 3. The international arena of Antarctica. Potentially favorable locations for CO 2 sequestration facilities are along the coastal regions, with favorable katabatic winds and supporting research stations that can benefit from the excess thermal waste of the cooling plants. 4. Design of the CO 2 sequestration facility The components of the proposed Antarctic facility are

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Jinhua Yu, Yuqing Wang, and Kevin Hamilton

displayed a warming from 0.5° to ∼0.6°C since the mid-nineteenth century ( Houghton et al. 2001 ), with warming from 0.25° to ∼0.5°C during the past several decades ( Rayner et al. 2003 ; Santer et al. 2006 ). State-of-the-art coupled general circulation models (CGCMs) with realistic anthropogenic forcing can simulate these warming trends reasonably well ( Houghton et al. 2001 ; Barnett et al. 2005 ). A TC can be regarded to the first approximation as a natural Carnot heat engine ( Emanuel 1986

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Nora R. Mascioli, Arlene M. Fiore, Michael Previdi, and Gustavo Correa

atmospheric aerosols, which typically cool the climate, both directly and via interactions with clouds ( Boucher et al. 2013 ). Aerosols are short-lived in the atmosphere and their emissions from anthropogenic sources are projected to decline over the next century. It is therefore important to understand how they are affecting the present climate in order to accurately project the effects of their removal. Here, we use a set of “single forcing” experiments performed by a state-of-the-art general

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A. Tuel and E. A. B. Eltahir

, precipitation, etc.) are defined with respect to the 1976–2005 reference period. 3. Quantifying the SLP response to upper-level circulation change CMIP5 GCMs robustly agree on the pattern of Northern Hemisphere upper-tropospheric circulation change under continued anthropogenic forcing: a strengthening of the midlatitude jet ( Barnes and Polvani 2013 ) and associated shift in the pattern of quasi-stationary waves ( Brandefelt and Krnich 2008 ) ( Fig. 3 ). A direct consequence of these changes is the

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Daisuke Nohara, Akio Kitoh, Masahiro Hosaka, and Taikan Oki

the Program for Climate Model Diagnosis and Intercomparison (PCMDI), as listed in Table 1 . Variables analyzed include the monthly mean precipitation, evaporation, and runoff of the 20C3M and SRES A1B experiments. Evaporation is obtained by calculating the latent heat flux divided by the latent heat of vaporization by ignoring fusion and sublimation. The 20C3M experiment has been simulated by AOGCM with natural (e.g., volcanoes and solar) and anthropogenic (e.g., greenhouse gases, ozone, and

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Thomas R. Knutson, Joseph J. Sirutis, Gabriel A. Vecchi, Stephen Garner, Ming Zhao, Hyeong-Seog Kim, Morris Bender, Robert E. Tuleya, Isaac M. Held, and Gabriele Villarini

extreme events. In addition, the statistical significance of some of our results might be enhanced through longer simulations even for the present models. Overall, our results provide further support to previous studies projecting that anthropogenic warming in the Atlantic basin over the twenty-first century will lead to fewer tropical storms and hurricanes overall but that the mean intensity of Atlantic hurricanes basinwide will increase. A projected increase in the frequency of very intense

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Adam A. Scaife, Chris K. Folland, Lisa V. Alexander, Anders Moberg, and Jeff R. Knight

observational data only for 1901–64. The results (not shown) were nearly the same, indicating that correlations between the NAO and the temperature and precipitation extremes are little affected by the choice of period. 6. Conclusions Using a novel set of experiments with a general circulation model, we have examined the effect of a realistic multidecadal increase in the NAO on surface climate extremes over Europe in winter. Using ensembles whose difference removes the modeled effects of anthropogenic

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Shakeel Asharaf and Bodo Ahrens

feedbacks ( Giorgetta et al. 2013 ). Physical parameters, such as, land use, orography, soil type, and vegetation fraction were used as RCM lower boundary conditions [see Smiatek et al. (2008) for more details about the physical parameters]. For the CCLM_B1 simulation, the driving data were taken from the experiment IPCC-AR4 MPI-ECHAM5 T63L31 MPI-OM GR1.5L40 SRESA1B run no.1: Atmosphere 6-hour values (IPCC-AR4 EH5-T63L31 OM-GR1.5L40 20C 1 6H) in the twentieth century with anthropogenic forcing B1 (EC

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Francis T. Hane

In their recent report, Coffel and Horton ( Coffel and Horton 2015 ) present calculations supporting their hypothesis that temperature changes caused by anthropogenic global warming (AGW) may result in aircraft weight restrictions for takeoffs at certain airports. I have recalculated the performance data the authors rely on referencing the Boeing 737–800 Flight Operations Manual (FOM) ( Boeing 2013a ). The FOM is the Federal Aviation Administration (FAA) certified document relied on by airline

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