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The general expression derived previously (A.P. Kouzov, J.V. Buldyreva, A.V. Sokolov, J. Chem. Phys. 149, 044305 (2018)) for the frequency‐dependent rotational relaxation matrix describing collisions of linear molecules is put into an energy‐corrected‐sudden (ECS) form convenient for spectra modeling. The translational interaction spectral functions characterizing the intracollisional dynamics and determining the relaxation matrix elements are factorized into a frequency‐dependent and an anisotropy ranks‐dependent parts. The particular case of isotropic Raman Q‐branch enables to establish connections of these parts with the adiabaticity factor accounting for the molecular rotation during the collision and the bimolecular relaxation rates, respectively. Analyses of these rates allow suggesting their realistic exponential‐polynomial model representations with a few adjustable parameters determined from fits on experimentally available Qiso line widths. Thanks to the universal character of the non‐Markovian approach, the same parameters enable realistic computations of N2 anisotropic Raman spectra up to very far spectral wings and without any additional parameter with respect to the Markovian ECS. [ABSTRACT FROM AUTHOR]

The article analyses the properties of mixed waves (wind waves and swell are not separated) in the Baltic Sea over the time interval of 40 years (1979–2018). Particular attention is paid to the presence and statistical significance of temporal trends in average annual significant wave heights (SWH) in various areas of the sea. The results are based on the output of mathematical modelling performed using the MIKE SW spectral wave model on an irregular forced by the ERA-Interim reanalysis data. The model was calibrated and validated using data from wave buoys located in different parts of the Baltic Sea. Average annual SWH had some upward trend in the first decade of the analysed forty years (1979–1989) while after 1990 the downward trend is dominant in almost the entire area of the Baltic Sea. The parametric and non-parametric statistical approaches showed that the trends revealed are statistically significant at a 90% level. Analysis of monthly average SWH using non-parametric methods revealed statistically significant SWH decrease at a 90% confidence level for February and March between 1990 and 2018 in all Baltic Sea sub-regions except the northern Bothnian Sea. • The average annual significant wave height in the Baltic Sea decreased in 1990–2018. • Decrease rate in the Baltic Proper (northern and southern parts) is 4–6 mm per year. • Decrease in monthly mean significant wave height occurred in February and March. • Statistical significance of changes was confirmed by parametric and non-parametric approaches. [ABSTRACT FROM AUTHOR]

We present results from large ensembles of projected twenty-first century changes in seasonal precipitation and near-surface air temperature for the nation of South Africa. These ensembles are a result of combining Monte Carlo projections from a human-Earth system model of intermediate complexity with pattern-scaled responses from climate models of the Coupled Model Intercomparison Project Phase 5 (CMIP5). These future ensemble scenarios consider a range of global actions to abate emissions through the twenty-first century. We evaluate distributions of surface-air temperature and precipitation change over three sub-national regions: western, central, and eastern South Africa. In all regions, we find that without any emissions or climate targets in place, there is a greater than 50% likelihood that mid-century temperatures will increase threefold over the current climate’s two-standard deviation range of variability. However, scenarios that consider more aggressive climate targets all but eliminate the risk of these salient temperature increases. A preponderance of risk toward decreased precipitation (3 to 4 times higher than increased) exists for western and central South Africa. Strong climate targets abate evolving regional hydroclimatic risks. Under a target to limit global climate warming to 1.5 °C by 2100, the risk of precipitation changes within South Africa toward the end of this century (2065–2074) is commensurate to the risk during the 2030s without any global climate target. Thus, these regional hydroclimate risks over South Africa could be delayed by 30 years and, in doing so, provide invaluable lead-time for national efforts to prepare, fortify, and/or adapt. [ABSTRACT FROM AUTHOR]

We demonstrate the enhancement in sensitivity of half Wheatstone bridge configurated magneto-resistive sensors with a design of the magnetic flux guide. The efficacy of our flux guide design, in comparison to the conventional micro-magnetic flux concentrator for improving the flux gain, is studied using finite element method and verified with the experimental result. We observed a sensitivity of 260%/mT for our half Wheatstone bridge sensor with a very small coercivity of 0.01 mT at room temperature. Our work will contribute to paving a road map for mass production of sensitive magneto-resistive sensors with small footprints (2.5 mm2 in this study). [ABSTRACT FROM AUTHOR]

Non‐Markovian effects having a strong influence on far‐wing intensities of spectroscopic signatures by molecular gases are analyzed theoretically with the use of a non‐Markovian relaxation matrix derived for rapidly colliding linear rotators (J. Chem. Phys. 149, 044305 [2018]) for the benchmark case of rototranslational Raman spectra of molecular nitrogen recorded at high densities up to very far wings (Phys. Lett. A 157, 44 [1991]). This matrix is built here on the base of the translational‐spectrum model of Birnbaum and Cohen and the recently computed, from known potential energy surfaces, two leading classical spectral moments (J. Ram. Spectrosc. 2020, DOI: 10.1002/jrs.5923). Theoretical intensity computations, going beyond the commonly used impact approximation, give much less overestimated values in the far wing and constitute a promising tool for getting accurate theoretical description of broad‐band spectra. [ABSTRACT FROM AUTHOR]

Explicit classical‐limit formulae for two leading spectral moments characterizing the anisotropy of the interaction potential are derived for fast collisions of linear rotators in the binary regime. With the help of these moments, model Fourier‐transforms of the time‐correlation functions comprising non‐Markovian effects are restored, which enables a novel and straight approach to pressure transformation of broad spectral bands and pressure‐broadening characteristics of (vib)rotational spectral lines, as demonstrated on a simple Markov‐limit example of isotropic and anisotropic Raman line widths of molecular nitrogen. [ABSTRACT FROM AUTHOR]

Abstract: The Massachusetts Institute of Technology Integrated Global System Model (IGSM) is designed for analyzing the global environmental changes that may result from anthropogenic causes, quantifying the uncertainties associated with the projected changes, and assessing the costs and environmental effectiveness of proposed policies to mitigate climate risk. The IGSM consists of the Massachusetts Institute of Technology Earth System Model (MESM) of intermediate complexity and the Economic Projections and Policy Analysis model. This paper documents the current version of the MESM, which includes a two‐dimensional (zonally averaged) atmospheric model with interactive chemistry coupled to the zonally averaged version of Global Land System model and an anomaly‐diffusing ocean model. [ABSTRACT FROM AUTHOR]

Interleukin-11 (IL-11) is a multifunctional cytokine implicated in several normal and pathological processes. The decoding of IL-11 function and development of IL-11-targeted drugs dictate the use of laboratory animals and need of the better understanding of species specificity of IL-11 signaling. Here, we present a method for the recombinant interleukin-11 (rIL-11) production from the important model animals, mouse and macaque. The purified mouse and macaque rIL-11 interact with extracellular domain of human IL-11 receptor subunit α and activate STAT3 signaling in HEK293 cells co-expressing human IL-11 receptors with efficacies resembling those of human rIL-11. Hence, the evolutionary divergence does not impair IL-11 signaling. Furthermore, compared to human rIL-11 its macaque orthologue is 8-fold more effective STAT3 activator, which favors its use for treatment of thrombocytopenia as a potent substitute for human rIL-11. Compared to IL-6, IL-11 signaling exhibits lower species specificity, likely due to less conserved intrinsic disorder propensity within IL-6 orthologues. The developed express method for preparation of functionally active macaque/mouse rIL-11 samples is suited for exploration of the molecular mechanisms underlying IL-11 action and for development of the drug candidates for therapy of oncologic/hematologic/inflammatory diseases related to IL-11 signaling. [ABSTRACT FROM AUTHOR]

The effect of substrates on the magnetic and transport properties of Ni2Mn15In0.5 ultra-thin films were studied theoretically and experimentally. High quality 8-nm films were grown by laser-assisted molecular beam epitaxy deposition. Magnetotransport measurements revealed that the films undergo electronic structure transformation similar to those of bulk materials at the martensitic transformation. The temperature of the transformation depends strongly on lattice parameters of the substrate. To explain this behavior, we performed DFT calculations on the system and found that different substrates change the relative stability of the ferromagnetic (FM) austenite and ferrimagnetic (FiM) martensite states. We conclude that the energy difference between the FM austenite and FiM martensite states in Ni2Mn15In0.5 films grown on MgO (001) substrates is ΔE = 0.20 eV per NiMnIn f.u, somewhat lower compared to ΔE = 0.24 eV in the bulk material with the same lattice parameters. When the lattice parameters of Ni2Mn15In0.5 film have values close to those of the MgO substrate, the energy difference becomes ΔE = 0.08 eV per NiMnIn f.u. These results suggest the possibility to control the martensitic transition in thin films through substrate engineering. [ABSTRACT FROM AUTHOR]

Interleukin-11 (IL-11) and S100P are oncoproteins co-expressed in numerous cancers, which might favor their interaction during oncogenesis. We have explored the possibility of this interaction by surface plasmon resonance spectroscopy, intrinsic fluorescence, and chemical crosslinking. Recombinant forms of IL-11 and S100P interact with each other under physiological level of calcium ions. IL-11 molecule has at least two S100P-binding sites with dissociation constants of 32 nM and 288 nM, which is 5–13-fold lower than its affinity to extracellular domain of IL-11 receptor subunit α. S100P does not alter IL-11-induced STAT3 activation in HEK293 cells co-expressing IL-11 receptors, but could affect other tumorigenic signaling pathways. The highly specific IL-11 – S100P interaction occurring under physiologically relevant conditions should be taken into consideration upon development of the antineoplastics inhibiting IL-11 signaling. [ABSTRACT FROM AUTHOR]

Conducting probabilistic climate projections with a particular climate model requires the ability to vary the model's characteristics, such as its climate sensitivity. In this study, the authors implement and validate a method to change the climate sensitivity of the National Center for Atmospheric Research (NCAR) Community Atmosphere Model, version 3 (CAM3), through cloud radiative adjustment. Results show that the cloud radiative adjustment method does not lead to physically unrealistic changes in the model's response to an external forcing, such as doubling CO2 concentrations or increasing sulfate aerosol concentrations. Furthermore, this method has some advantages compared to the traditional perturbed physics approach. In particular, the cloud radiative adjustment method can produce any value of climate sensitivity within the wide range of uncertainty based on the observed twentieth century climate change. As a consequence, this method allows Monte Carlo-type probabilistic climate forecasts to be conducted where values of uncertain parameters not only cover the whole uncertainty range, but cover it homogeneously. Unlike the perturbed physics approach that can produce several versions of a model with the same climate sensitivity but with very different regional patterns of change, the cloud radiative adjustment method can only produce one version of the model with a specific climate sensitivity. As such, a limitation of this method is that it cannot cover the full uncertainty in regional patterns of climate change. [ABSTRACT FROM AUTHOR]

Although policymaking in response to the climate change threat is essentially a challenge of risk management, most studies of the relation of emissions targets to desired climate outcomes are either deterministic or subject to a limited representation of the underlying uncertainties. Monte Carlo simulation, applied to the MIT Integrated Global System Model (an integrated economic and earth system model of intermediate complexity), is used to analyze the uncertain outcomes that flow from a set of century-scale emissions paths developed originally for a study by the U.S. Climate Change Science Program. The resulting uncertainty in temperature change and other impacts under these targets is used to illustrate three insights not obtainable from deterministic analyses: that the reduction of extreme temperature changes under emissions constraints is greater than the reduction in the median reduction; that the incremental gain from tighter constraints is not linear and depends on the target to be avoided; and that comparing median results across models can greatly understate the uncertainty in any single model. [ABSTRACT FROM AUTHOR]

The impact of carbon–nitrogen dynamics in terrestrial ecosystems on the interaction between the carbon cycle and climate is studied using an earth system model of intermediate complexity, the MIT Integrated Global Systems Model (IGSM). Numerical simulations were carried out with two versions of the IGSM’s Terrestrial Ecosystems Model, one with and one without carbon–nitrogen dynamics. Simulations show that consideration of carbon–nitrogen interactions not only limits the effect of CO2 fertilization but also changes the sign of the feedback between the climate and terrestrial carbon cycle. In the absence of carbon–nitrogen interactions, surface warming significantly reduces carbon sequestration in both vegetation and soil by increasing respiration and decomposition (a positive feedback). If plant carbon uptake, however, is assumed to be nitrogen limited, an increase in decomposition leads to an increase in nitrogen availability stimulating plant growth. The resulting increase in carbon uptake by vegetation exceeds carbon loss from the soil, leading to enhanced carbon sequestration (a negative feedback). Under very strong surface warming, however, terrestrial ecosystems become a carbon source whether or not carbon–nitrogen interactions are considered. Overall, for small or moderate increases in surface temperatures, consideration of carbon–nitrogen interactions result in a larger increase in atmospheric CO2 concentration in the simulations with prescribed carbon emissions. This suggests that models that ignore terrestrial carbon–nitrogen dynamics will underestimate reductions in carbon emissions required to achieve atmospheric CO2 stabilization at a given level. At the same time, compensation between climate-related changes in the terrestrial and oceanic carbon uptakes significantly reduces uncertainty in projected CO2 concentration. [ABSTRACT FROM AUTHOR]

The response of the ocean’s meridional overturning circulation (MOC) to increased greenhouse gas forcing is examined using a coupled model of intermediate complexity, including a dynamic 3-D ocean subcomponent. Parameters are the increase in CO2 forcing (with stabilization after a specified time interval) and the model’s climate sensitivity. In this model, the cessation of deep sinking in the north “Atlantic” (hereinafter, a “collapse”), as indicated by changes in the MOC, behaves like a simple bifurcation. The final surface air temperature (SAT) change, which is closely predicted by the product of the radiative forcing and the climate sensitivity, determines whether a collapse occurs. The initial transient response in SAT is largely a function of the forcing increase, with higher sensitivity runs exhibiting delayed behavior; accordingly, high CO2-low sensitivity scenarios can be assessed as a recovering or collapsing circulation shortly after stabilization, whereas low CO2-high sensitivity scenarios require several hundred additional years to make such a determination. We also systemically examine how the rate of forcing, for a given CO2 stabilization, affects the ocean response. In contrast with previous studies based on results using simpler ocean models, we find that except for a narrow range of marginally stable to marginally unstable scenarios, the forcing rate has little impact on whether the run collapses or recovers. In this narrow range, however, forcing increases on a time scale of slow ocean advective processes results in weaker declines in overturning strength and can permit a run to recover that would otherwise collapse. [ABSTRACT FROM AUTHOR]

When the dimensions of a metallic conductor are reduced so that they become comparable to the de Broglie wavelengths of the conduction electrons, the absence of scattering results in ballistic electron transport and the conductance becomes quantized. In ferromagnetic metals, the spin angular momentum of the electrons results in spin-dependent conductance quantization and various unusual magnetoresistive phenomena. Theorists have predicted a related phenomenon known as ballistic anisotropic magnetoresistance (BAMR). Here we report the first experimental evidence for BAMR by observing a stepwise variation in the ballistic conductance of cobalt nanocontacts as the direction of an applied magnetic field is varied. Our results show that BAMR can be positive and negative, and exhibits symmetric and asymmetric angular dependences, consistent with theoretical predictions. [ABSTRACT FROM AUTHOR]

Simulation of both the climate of the twentieth century and a future climate change requires taking into account numerous forcings, while climate sensitivities of general circulation models are defined as the equilibrium surface warming due to a doubling of atmospheric CO2 concentration. A number of simulations with the Massachusetts Institute of Technology (MIT) climate model of intermediate complexity with different forcings have been carried out to study to what extent sensitivity to changes in CO2 concentration (SCO2) represent sensitivities to other forcings. The MIT model, similar to other models, shows a strong dependency of the simulated surface warming on the vertical structure of the imposed forcing. This dependency is a result of “semidirect” effects in the simulations with localized tropospheric heating. A method for estimating semidirect effects associated with different feedback mechanisms is presented. It is shown that forcing that includes these effects is a better measure of expected surface warming than a forcing that accounts for stratospheric adjustment only. Simulations with the versions of the MIT model with different strengths of cloud feedback show that, for the range of sensitivities produced by existing GCMs, SCO2 provides a good measure of the model sensitivity to other forcings. In the case of strong cloud feedback, sensitivity to the increase in CO2 concentration overestimates model sensitivity to both negative forcings, leading to the cooling of the surface and “black carbon”–like forcings with elevated heating. This is explained by the cloud feedback being less efficient in the case of increasing sea ice extent and snow cover or by the above-mentioned semidirect effects, which are absent in the CO2 simulations, respectively. [ABSTRACT FROM AUTHOR]

The transient response of both surface air temperature and deep ocean temperature to an increasing external forcing strongly depends on climate sensitivity and the rate of the heat mixing into the deep ocean, estimates for both of which have large uncertainty. In this paper a method for estimating rates of oceanic heat uptake for coupled atmosphere-ocean general circulation models from results of transient climate change simulations is described. For models considered in this study, the estimates vary by a factor of 2½. Nevertheless, values of oceanic heat uptake for all models fall in the range implied by the climate record for the last century. It is worth noting that the range of the model values is narrower than that consistent with observations and thus does not provide a full measure of the uncertainty in the rate of oceanic heat uptake. [ABSTRACT FROM AUTHOR]

Focuses on the methodology of performing formal uncertainty analysis in climate projections using the MIT 2 dimensional climate model. Climatic impact of greenhouse gases; Uncertainties in climate modeling; How to describe uncertainty in climate change for prescribed changes in radiative forces.

Collisional mixing of (vib)rotational lines appearing in spectroscopic signatures of dense planetary atmospheres and combustion environments is rigorously handled for the case of two linear colliders in terms of incomplete (non-Markovian) collisions related to off-energy-shell scattering amplitudes. Contrary to the standard impact-approximation approaches valid solely in band-centre regions, a new uniform broadband spectrum description is developed on the basis of a frequency-dependent rotational relaxation matrix which accurately accounts for the influence of the extra photon energy with respect to the molecular transitions. This matrix is built using a symmetric Liouville-space metric and obeys all known fundamental rules. Its direct calculation from refined potential-energy surfaces and promising modeling methods for forthcoming practical computations are outlined. A simple preliminary test for N2-N2 isotropic Raman line widths argues in favor of considerable effects of the internal perturber's structure on modeled spectral characteristics. [ABSTRACT FROM AUTHOR]

The authors have fabricated a thin film copper phthalocyanine to crystalline ferroelectric copolymer poly(vinylidene fluoride with trifluoroethylene) heterojunction diode. The formation of a diode is expected from the band offsets between the two thin film molecular systems, as ascertained from combined photoemission and inverse photoemission studies. From the temperature and field dependence of the heterojunction, dipole interactions are implicated at the interface between copper phthalocyanine and poly(vinylidene fluoride with trifluoroethylene) and affect the band offsets and resultant diode properties. [ABSTRACT FROM AUTHOR]

New ExoMol line lists AloHa for aluminium hydride (AlH and AlD) are presented improving the previous line lists WYLLoT. The revision is motivated by the recent experimental measurements and astrophysical findings involving the highly excited rotational states of AlH in its A 1Π − X 1Σ+ system. A new high-resolution emission spectrum of 10 bands from the A 1Π − X 1Σ+ system of AlD, in the region 17 300–32 000 cm−1 was recorded with a Fourier transform spectrometer, which probes the predissociative A 1Π v  = 2 state. The AlD new line positions are combined with all available experimental data on AlH and AlD to construct a comprehensive set of empirical rovibronic energies of AlH and AlD covering the X 1Σ+ and A 1Π electronic states using the MARVEL approach. We then refine the spectroscopic model WYLLoT to our experimentally derived energies using the nuclear-motion code Duo and use this fit to produce improved line lists for 27AlH, 27AlD, and 26AlH with a better coverage of the rotationally excited states of A 1Π in the predissociative energy region. The lifetimes of the predissociative states are estimated and are included in the line list using the new ExoMol data structure, alongside the temperature-dependent continuum contribution to the photoabsorption spectra of AlH. The new line lists are shown to reproduce the experimental spectra of both AlH and AlD well, and to describe the AlH absorption in the recently reported Proxima Cen spectrum, including the strong predissociative line broadening. The line lists are included into the ExoMol data base www.exomol.com. [ABSTRACT FROM AUTHOR]

A simple and practical ac modulation method to reduce the hysteresis in tunneling magnetoresistive (TMR) sensor is demonstrated. It is shown that with a suitable ac modulation magnetic field that is applied along the sensing direction of the TMR sensor, the hysteresis in the sensor can be reduced to a negligible level. Also, depending on the amplitude of the modulation field, the sensitivity and the dynamic range of the TMR sensor can be tuned to meet practical requirements in specific applications. The influence of the modulation on the noise of TMR sensor is also studied. [ABSTRACT FROM AUTHOR]

Probabilistic estimates of climate system properties often rely on the comparison of model simulations to observed temperature records and an estimate of the internal climate variability. In this study, we investigate the sensitivity of probability distributions for climate system properties in the Massachusetts Institute of Technology Earth System Model to the internal variability estimate. In particular, we derive probability distributions using the internal variability extracted from 25 different Coupled Model Intercomparison Project Phase 5 models. We further test the sensitivity by pooling variability estimates from models with similar characteristics. We find the distributions to be highly sensitive when estimating the internal variability from a single model. When merging the variability estimates across multiple models, the distributions tend to converge to a wider distribution for all properties. This suggests that using a single model to approximate the internal climate variability produces distributions that are too narrow and do not fully represent the uncertainty in the climate system property estimates. Key Points: Estimates are highly sensitive when using a single source to approximate internal variabilityProbabilistic estimates are too narrow if the internal variability comes from a single modelEstimates tend to converge when enough samples of internal variability are used [ABSTRACT FROM AUTHOR]

For over 20 years, the Massachusetts Institute of Technology Earth System Model (MESM) has been used extensively for climate change research. The model is under continuous development with components being added and updated. To provide transparency in the model development, we perform a baseline evaluation by comparing model behavior and properties in the newest version to the previous model version. In particular, changes resulting from updates to the land surface model component and the input forcings used in historical simulations of climate change are investigated. We run an 1800-member ensemble of MESM historical climate simulations where the model parameters that set climate sensitivity, the rate of ocean heat uptake, and the net anthropogenic aerosol forcing are systematically varied. By comparing model output to observed patterns of surface temperature changes and the linear trend in the increase in ocean heat content, we derive probability distributions for the three model parameters. Furthermore, we run a 372-member ensemble of transient climate simulations where all model forcings are fixed and carbon dioxide concentrations are increased at the rate of 1%year-1. From these runs, we derive response surfaces for transient climate response and thermosteric sea level rise as a function of climate sensitivity and ocean heat uptake. We show that the probability distributions shift towards higher climate sensitivities and weaker aerosol forcing when using the new model and that the climate response surfaces are relatively unchanged between model versions. Because the response surfaces are independent of the changes to the model forcings and similar between model versions with different land surface models, we suggest that the change in land surface model has limited impact on the temperature evolution in the model. Thus, we attribute the shifts in parameter estimates to the updated model forcings. [ABSTRACT FROM AUTHOR]

A response by Al Sokolov and colleagues to a letter to the editor on their article on the conductance of ferromagnetic point contacts at room temperature as a function of the angle of an applied magnetic field, published in a 2007 issue of "Nature Nanotechnology," is presented.

For over twenty years, the Massachusetts Institute of Technology Earth System Model (MESM) has been used extensively for climate change research. The model is under continuous development with components being added or updated. To provide transparency in the model development, we perform a baseline evaluation of the newest version by comparing model behavior and properties to the previous model version. In particular, the impacts resulting from updates to the land surface model component and the input forcings used in historical simulations of climate change are investigated. We run an 1800-member ensemble of MESM historical climate simulations where the model parameters that set climate sensitivity, ocean heat uptake, and the net anthropogenic aerosol forcing are systematically varied. By comparing model output to observed patterns of surface temperature changes, the linear trend in the increase in ocean heat content, and upper-air temperature changes, we derive probability distributions for the three model parameters. Furthermore, we run a 372-member ensemble of transient climate simulations where model forcings are held fixed, absent an increase in carbon dioxide concentrations at the rate of 1 \% per year. From these runs, we derive a response surface for transient climate response and thermosteric sea level rise as a function of climate sensitivity and ocean heat uptake. We compare the probability distributions and response surfaces derived using the current version of MESM to the preceding version to evaluate the impact of the updated land surface model and forcing suite. We show that the probability distributions shift towards higher climate sensitivities and weaker aerosol forcing in response to the new forcing suite. The climate response surfaces are relatively unchanged between model versions, indicating that the updated land surface model has limited impact on temperature evolution in the model. [ABSTRACT FROM AUTHOR]

Historical time series of surface temperature and ocean heat content changes are commonly used metrics to diagnose climate change and estimate properties of the climate system. We show that recent trends, namely the slowing of surface temperature rise at the beginning of the 21st century and the acceleration of heat stored in the deep ocean, have a substantial impact on these estimates. Using the Massachusetts Institute of Technology Earth System Model (MESM), we vary three model parameters that influence the behavior of the climate system: effective climate sensitivity (ECS), the effective ocean diffusivity of heat anomalies by all mixing processes (Kv), and the net anthropogenic aerosol forcing scaling factor. Each model run is compared to observed changes in decadal mean surface temperature anomalies and the trend in global mean ocean heat content change to derive a joint probability distribution function for the model parameters. Marginal distributions for individual parameters are found by integrating over the other two parameters. To investigate how the inclusion of recent temperature changes affects our estimates, we systematically include additional data by choosing periods that end in 1990, 2000, and 2010. We find that estimates of ECS increase in response to rising global surface temperatures when data beyond 1990 are included, but due to the slowdown of surface temperature rise in the early 21st century, estimates when using data up to 2000 are greater than when data up to 2010 are used. We also show that estimates of Kv increase in response to the acceleration of heat stored in the ocean as data beyond 1990 are included. Further, we highlight how including spatial patterns of surface temperature change modifies the estimates. We show that including latitudinal structure in the climate change signal impacts properties with spatial dependence, namely the aerosol forcing pattern, more than properties defined for the global mean, climate sensitivity, and ocean diffusivity. [ABSTRACT FROM AUTHOR]

Growing societal pressures, technological trends and government and industry actions are moving the world toward decarbonization and away from the "business-as-usual". As such, the concept of a single/obvious "business as usual" or "reference" scenario is no longer relevant. Instead, there are multiple plausible futures that should be explored. We contribute one such scenario that carefully considers emission-reduction trends and actions that are likely in the future, absent globally coordinated mitigation effort. We explore the long-term implications for energy, emissions, and temperature outcomes if the world continues to address climate change in the way it has so far—through piecemeal actions and growing social and technological pressures. This Growing Pressures scenario results in a central scenario outcome of about 3 °C of surface temperature warming, which is higher than the "well below 2 °C" level aspired by the Paris Agreement, but lower than many widely used "no-policy" scenarios. Ongoing and growing pressures of change, the roots of which are clearly visible today, could deliver a plausible energy transition scenario to near zero emissions that plays out over the coming century. While a more aggressive transition is clearly required, this finding highlights the need to bring actions forward in time to achieve an improved outcome making use of clearly identifiable policies and technologies. [ABSTRACT FROM AUTHOR]

The oxo-bridged hexanuclear iron cluster formulated [Fe III6 (μ4-O)2(edteH)2(piv)4(SCN)4]·2MeCN·2H2O (1) (where edteH = N,N,N′,N′-tetrakis(2-hydroxyethyl)ethylenediamine; piv = pivalic acid) has been synthesized by the reaction of FeCl2·4H2O with edteH4 and piv in the presence of KSCN in CH2Cl2/MeCN. The single crystal X-ray measurements indicated that the cluster is centrosymmetric in structure. The magnetic study demonstrated the presence of very strong antiferromagnetic coupling between the iron centers and the Brillouin fitting showed the best fit with S = 5/2 and g = 1.87. In addition, the water oxidation activity of the cluster has been studied by electrochemical techniques. Electrochemical experiments revealed that the electrode modified by 1 has high efficiency for the oxidation of water and needs an overpotential of 484 mV under a constant current density of 15 mA cm−2 with a Tafel slope of 114 mV dec−1 in neutral media. Experiments indicated that in the presence of 1, a yellow solid film was formed on the electrode surface under the applied electrochemical conditions. This yellow material is likely a compound of iron and oxygen and has a crystalline nature. Our findings revealed that along with the cluster, this compound is active in water oxidation reactions. [ABSTRACT FROM AUTHOR]

In this study, a hysteresis reduction technique for tunneling magnetoresistive (TMR) sensor for low magnetic field sensing is proposed, where a small ac modulation magnetic field is applied. The magnetic tunnel junctions (MTJs) were connected into an asymmetric Wheatstone bridge to form a sensor, and the output voltage of the TMR sensor was measured using a small ac modulation field and test field along the sensor’s sensing direction. The results showed that hysteresis in the TMR sensor can be effectively reduced to exhibit a linear response. Further, the frequency response of the TMR sensor was studied. Finally, the feasibility of the TMR sensor for low-field detection with small ac modulation was demonstrated. [ABSTRACT FROM AUTHOR]

• Crystallization kinetics of cross-linked PBT was studied by DSC and FSC. • Cross-links in PBT strongly retard crystallization and homogeneous nucleation. • Cross-links in PBT increase the glass transition temperature. • POM analysis confirms the retardation of crystallization. Kinetics of crystallization of the samples of cross-linked polybutylene terephthalate with different cross-link densities was studied experimentally using conventional differential scanning calorimetry (cooling rates 5 to 40 K·min–1) and fast scanning calorimetry (cooling rates 0.5 to 5000 K·s–1). The samples were obtained by copolycondensation of terephthaloyl chloride, 1,4-butanediol, and glycerol. The cross-linking degree was characterized using 1H NMR spectroscopy. An increase of the number of glycerol cross-links in polymer leads to a decrease in the crystallization and melting temperatures and suppression of crystallization process. The critical rate of crystallization decreases monotonically with increasing cross-linking degree from 2700 K·s–1 for linear polybutylene terephthalate to 110 K·s–1 for the sample with 270 mol·m–3 cross-link density. At the cross-link densities higher than 270 mol·m–3, the polymer does not crystallize even at 5 K·min–1 cooling rate. The observed dependence of the cold crystallization enthalpy on the previous cooling rate suggests that the homogeneous nuclei formation process also slows down with an increase in the cross-linking degree. [ABSTRACT FROM AUTHOR]

wide variety of scenarios for future development have played significant roles in climate policy discussions. This paper presents projections of greenhouse gas (GHG) concentrations, sea level rise due to thermal expansion and glacial melt, oceanic acidity, and global mean temperature increases computed with the MIT Integrated Global Systems Model (IGSM) using scenarios for twenty-first century emissions developed by three different groups: intergovernmental (represented by the Intergovernmental Panel on Climate Change), government (represented by the U.S. government Climate Change Science Program) and industry (represented by Royal Dutch Shell plc). In all these scenarios the climate system undergoes substantial changes. By 2100, the CO concentration ranges from 470 to 1020 ppm compared to a 2000 level of 365 ppm, the CO-equivalent concentration of all greenhouse gases ranges from 550 to 1780 ppm in comparison to a 2000 level of 415 ppm, oceanic acidity changes from a current pH of around 8 to a range from 7.63 to 7.91, in comparison to a pH change from a preindustrial level by 0.1 unit. The global mean temperature increases by 1.8 to 7.0°C relative to 2000. Such increases will require considerable adaptation of many human systems and will leave some aspects of the earth's environment irreversibly changed. Thus, the remarkable aspect of these different approaches to scenario development is not the differences in detail and philosophy but rather the similar picture they paint of a world at risk from climate change even if there is substantial effort to reduce emissions. [ABSTRACT FROM AUTHOR]

We present revised probability density functions for climate model parameters (effective climate sensitivity, the rate of deep-ocean heat uptake, and the strength of the net aerosol forcing) that are based on climate change observations from the 20th century. First, we compare observed changes in surface, upper-air, and deep-ocean temperature changes against simulations of 20th century climate in which the climate model parameters were systematically varied. The estimated 90% range of effective climate sensitivity is 2–5 K but no corresponding upper bound can be placed on the equilibrium climate sensitivity. The net aerosol forcing strength for the 1980s has 90% bounds of −0.70 to −0.27 W m−2. The rate of deep-ocean heat uptake corresponds to an effective diffusivity, , with a 90% range of 0.04–4.1 cm2 s−1. Second, we estimate the effective climate sensitivity and rate of deep-ocean heat uptake for 11 of the IPCC AR4 AOGCMs. By comparing against the acceptable combinations inferred from the observations, we conclude that the rates of deep-ocean heat uptake for the majority of AOGCMs lie above the observationally based median value. This implies a bias in the predictions inferred from the IPCC models alone. [ABSTRACT FROM AUTHOR]

The sensitivity of the ocean’s climate to the diapycnal diffusivity in the ocean is studied for a global warming scenario in which CO2 increases by 1% yr-1 for 75 yr. The thermohaline circulation slows down for about 100 yr and recovers afterward, for any value of the diapycnal diffusivity. The rates of slowdown and of recovery, as well as the percentage recovery of the circulation at the end of 1000-yr integrations, are variable, but a direct relation with the diapycnal diffusivity cannot be found. At year 70 (when CO2 has doubled) an increase of the diapycnal diffusivity from 0.1 to 1.0 cm2 s-1 leads to a decrease in surface air temperature of about 0.4 K and an increase in sea level rise of about 4 cm. The steric height gradient is divided into thermal component and haline component. It appears that, in the first 60 yr of simulated global warming, temperature variations dominate the salinity ones in weakly diffusive models, whereas the opposite occurs in strongly diffusive models. The analysis of the vertical heat balance reveals that deep-ocean heat uptake is due to reduced upward isopycnal diffusive flux and parameterized-eddy advective flux. Surface warming, induced by enhanced CO2 in the atmosphere, leads to a reduction of the isopycnal slope, which translates into a reduction of the above fluxes. The amount of reduction is directly related to the magnitude of the isopycnal diffusive flux and parameterized-eddy advective flux at equilibrium. These latter fluxes depend on the thickness of the thermocline at equilibrium and hence on the diapycnal diffusion. Thus, the increase of deep-ocean heat uptake with diapycnal diffusivity is an indirect effect that the latter parameter has on the isopycnal diffusion and parameterized-eddy advection. [ABSTRACT FROM AUTHOR]

The ocean heat uptake (OHU) is studied using the Massachusetts Institute of Technology (MIT) ocean general circulation model (OGCM) with idealized ocean geometry. The OGCM is coupled with a statistical–dynamic atmospheric model. The simulation of OHU in the coupled model is consistent with other coupled ocean–atmosphere GCMs in a transient climate change when CO[sub 2] concentration increases by 1% yr[sup –1] . The global average surface air temperature increases by 1.7°C at the time of CO[sub 2] concentration doubling (year 70). The ocean temperature increases by about 1.0°C near the surface, 0.1°C at 1000 m in the Pacific, and 0.3°C in the Atlantic. The maximum overturning circulation (MOTC) in the Atlantic at 1350 m decreases by about 4.5 Sv (1 Sv ≡ 10[sup 6] m[sup 3] s[sup –1] ). The center of MOTC drifts upward about 300 m, and therefore a large OTC anomaly (14 Sv) is found at 2700 m. The MOTC recovers gradually, but the OTC anomaly at 2700 m does not seem to recover after CO[sub 2] concentration is kept constant during 400-yr simulation period. The diagnosis of heat flux convergence anomaly indicates that the warming in the lower latitudes of the Atlantic is associated with large-scale advection. But, the warming in the higher latitudes is associated with the heat brought down from the surface by convection and eddy mixing. In global average, the treatments of convection and eddy mixing are the two main factors affecting the OHU. The uncertainty of OHU due to subgrid-scale eddy mixing is studied. In the MIT OGCM this mixing is a combination of Gent–McWilliams bolus advection and Redi isopycnal diffusion (GMR), with a single diffusivity being used to calculate the isopycnal and thickness diffusion. Experiments are carried out with values of the diffusivity of 500, 1000, and 2000 m[sup 2] s[sup –1] . The total OHU is insensitive to these changes. The insensitivity is mainly due to the changes in the vertical heat flux by GMR mixing being compensated by changes in the other vertical heat flux components. In the Atlantic when the diffusivity is reduced from 1000 to 500 m[sup 2] s[sup –1] , the surface warming can penetrate deeper. Therefore, the warming decreases by about 0.15°C above 2000 m but increases by about 0.15°C below 2500 m. Similarly, when the diffusivity is increased from 1000 to 2000 m[sup 2] s[sup –1] , the surface warming becomes shallower; the warming increases by about 0.2°C above 1000 m but decreases by about 0.2°C below 1000 m. These changes in the vertical distribution of the OHU also contribute to the insensitivity of the total OHU to changes in the GMR mixing. The analysis of heat flux convergence indicates that the difference of OHU seems to be associated with the MOTC circulation. [ABSTRACT FROM AUTHOR]

The deep-ocean heat uptake (DOHU) in transient climate changes is studied using an ocean general circulation model (OGCM) and its adjoint. The model configuration consists of idealized Pacific and Atlantic basins. The model is forced with the anomalies of surface heat and freshwater fluxes from a global warming scenario with a coupled model using the same ocean configuration. In the global warming scenario, CO[SUB2] concentration increases) 1yr[SUP-1]. The heat uptake calculated from the coupled model and from the adjoint are virtually identical, showing that the heat uptake by the OGCM is a linear process. After 70 yr the ocean heat uptake is almost evenly distributed within the layers above 200 m, between 200 and 700 m, and below 700 m (about 20 × 10[SUP22] J in each). The effect of anomalous surface freshwater flux on the DOHU is negligible. Analysis of the Coupled Model Intercomparison Project (CMIP-2) data for the same global warming scenario shows that qualitatively similar results apply to coupled atmosphere-ocean GCMs. The penetration of surface heat flux to the deep ocean in the OGCM occurs mainly in the North Atlantic and the Southern Ocean, since both the sensitivity of DOHU to the surface heat flux and the magnitude of anomalous surface heat flux are large in these two regions. The DOHU relies on the reduction of convection and Gent-McWilliams--Redi mixing in the North Atlantic, and the reduction of Gent--McWilliams--Redi mixing in the Southern Ocean. [ABSTRACT FROM AUTHOR]

We derive joint probability density distributions for three key uncertain properties of the climate system, using an optimal fingerprinting approach to compare simulations of an intermediate complexity climate model with three distinct diagnostics of recent climate observations. On the basis of the marginal probability distributions, the 5 to 95% confidence intervals are 1.4 to 7.7 kelvin for climate sensitivity and -0.30 to -0.95 watt per square meter for the net aerosol forcing. The oceanic heat uptake is not well constrained, but ocean temperature observations do help to constrain climate sensitivity. The uncertain in the net aerosol forcing is much smaller than the uncertainty range for the indirect aerosol forcing alone given in the Intergovernmental Panel on Climate Change Third Assessment Report. [ABSTRACT FROM AUTHOR]

A nonequilibrium rapid-quenching method has been used to fabricate NiMnIn and NiMnGa alloys that are chemically and morphologically similar but crystallographically and physically very different. NiMnGa crystallizes in a Ni2In-type hexagonal structure, whereas NiMnIn is a cubic Heusler alloy. Both alloys yield a topological Hall effect contribution corresponding to bubble-type skyrmion spin structures, but it occurs in much lower magnetic fields in NiMnIn as compared to NiMnGa. The effect is unrelated to net Dzyaloshinskii-Moriya interactions, which are absent in both alloys due to their inversion-symmetric crystal structures. Based on magnetic-force microscopy, we explain the difference between the two alloys by magnetocrystalline anisotropy and uniaxial and cubic anisotropies yielding full-fledged and reduced topological Hall effects, respectively. Since NiMnIn involves small magnetic fields (0.02–0.3 kOe) at and above room temperature, it is of potential interest in spin electronics. [ABSTRACT FROM AUTHOR]

The effect of intermediate interfacial oxidation on the in-plane magnetization of multilayer stack Pt/Co/Gd 2 O 3 , on a p-type silicon substrate, has been investigated by magneto-optical Kerr effect (MOKE) measurements, the anomalous Hall effect, and magnetoresistance measurements. While voltage controlled perpendicular magnetic anisotropy of a metal/oxide heterostructure is known, this heterostructure displays an inverse relationship between voltage and coercivity. The anomalous Hall effect demonstrates a significant change in hysteresis, with the applied bias sign. There is a higher perpendicular magnetic anisotropy with positive bias exposure. [ABSTRACT FROM AUTHOR]

Static thermal requirements ( T ) are widely used to model the timing of phenology, yet may significantly bias phenological projections under future warming conditions, since recent studies argue that climate warming will increase T for triggering vegetation phenology. This study investigates the temporal trend and inter-annual variation of T derived from satellite-based spring and autumn phenology for the alpine and temperate vegetation on the Tibetan Plateau from 1982 to 2011. While we detected persistent warming in both spring and autumn across this time period, we did not find a corresponding long-term increase in T for most of the study area. Instead, we found a substantial interannual variability of T that could be largely explained by interannual variations in other climatic factors. Specifically, the number of chilling days and fall temperature were robust variables for predicting the dynamics of T for spring onset and autumn senescence, respectively. Phenology models incorporating a dynamic T algorithm performed slightly better than those with static T values in reproducing phenology derived from SPOT-VGT NDVI data. To assess the degree to which T variation affects large-scale phenology and carbon cycling projections, we compared the output from versions of the Terrestrial Ecosystem Model that incorporated static and dynamic T values in their phenology algorithms. Under two contrasting future climate scenarios, the dynamic T setting reduced the projected growing season length by up to 1-3 weeks by the late twenty-first century, leading to a maximum reduction of 8.9 % in annual net primary production and ~15 % in cumulative net ecosystem production for this region. Our study reveals that temporal dynamics of T meaningfully affect the carbon dynamics on the Tibetan Plateau, and should thus be considered in future ecosystem carbon modeling. [ABSTRACT FROM AUTHOR]

In the circumpolar north (45–90°N), permafrost plays an important role in vegetation and carbon (C) dynamics. Permafrost thawing has been accelerated by the warming climate and exerts a positive feedback to climate through increasing soil C release to the atmosphere. To evaluate the influence of permafrost on C dynamics, changes in soil temperature profiles should be considered in global C models. This study incorporates a sophisticated soil thermal model (STM) into a dynamic global vegetation model (LPJ-DGVM) to improve simulations of changes in soil temperature profiles from the ground surface to 3 m depth, and its impacts on C pools and fluxes during the 20th and 21st centuries. With cooler simulated soil temperatures during the summer, LPJ-STM estimates ~ 0.4 Pg C yr − 1 lower present-day heterotrophic respiration but ~ 0.5 Pg C yr − 1 higher net primary production than the original LPJ model resulting in an additional 0.8 to 1.0 Pg C yr − 1 being sequestered in circumpolar ecosystems. Under a suite of projected warming scenarios, we show that the increasing active layer thickness results in the mobilization of permafrost C, which contributes to a more rapid increase in heterotrophic respiration in LPJ-STM compared to the stand-alone LPJ model. Except under the extreme warming conditions, increases in plant production due to warming and rising CO 2 , overwhelm the e nhanced ecosystem respiration so that both boreal forest and arctic tundra ecosystems remain a net C sink over the 21st century. This study highlights the importance of considering changes in the soil thermal regime when quantifying the C budget in the circumpolar north. [ABSTRACT FROM AUTHOR]

Globally, 15.5 million km of land are currently identified as protected areas, which provide society with many ecosystem services including climate-change mitigation. Combining a global database of protected areas, a reconstruction of global land-use history, and a global biogeochemistry model, we estimate that protected areas currently sequester 0.5 Pg C annually, which is about one fifth of the carbon sequestered by all land ecosystems annually. Using an integrated earth systems model to generate climate and land-use scenarios for the twenty-first century, we project that rapid climate change, similar to high-end projections in IPCC's Fifth Assessment Report, would cause the annual carbon sequestration rate in protected areas to drop to about 0.3 Pg C by 2100. For the scenario with both rapid climate change and extensive land-use change driven by population and economic pressures, 5.6 million km of protected areas would be converted to other uses, and carbon sequestration in the remaining protected areas would drop to near zero by 2100. [ABSTRACT FROM AUTHOR]

In this study, we present a new modeling framework and a large ensemble of climate projections to investigate the uncertainty in regional climate change over the United States (US) associated with four dimensions of uncertainty. The sources of uncertainty considered in this framework are the emissions projections, global climate system parameters, natural variability and model structural uncertainty. The modeling framework revolves around the Massachusetts Institute of Technology (MIT) Integrated Global System Model (IGSM), an integrated assessment model with an Earth System Model of Intermediate Complexity (EMIC) (with a two-dimensional zonal-mean atmosphere). Regional climate change over the US is obtained through a two-pronged approach. First, we use the IGSM-CAM framework, which links the IGSM to the National Center for Atmospheric Research (NCAR) Community Atmosphere Model (CAM). Second, we use a pattern-scaling method that extends the IGSM zonal mean based on climate change patterns from various climate models. Results show that the range of annual mean temperature changes are mainly driven by policy choices and the range of climate sensitivity considered. Meanwhile, the four sources of uncertainty contribute more equally to end-of-century precipitation changes, with natural variability dominating until 2050. For the set of scenarios used in this study, the choice of policy is the largest driver of uncertainty, defined as the range of warming and changes in precipitation, in future projections of climate change over the US. [ABSTRACT FROM AUTHOR]

We designed scenarios for impact assessment that explicitly address policy choices and uncertainty in climate response. Economic projections and the resulting greenhouse gas emissions for the 'no climate policy' scenario and two stabilization scenarios: at 4.5 W/m and 3.7 W/m by 2100 are provided. They can be used for a broader climate impact assessment for the US and other regions, with the goal of making it possible to provide a more consistent picture of climate impacts, and how those impacts depend on uncertainty in climate system response and policy choices. The long-term risks, beyond 2050, of climate change can be strongly influenced by policy choices. In the nearer term, the climate we will observe is hard to influence with policy, and what we actually see will be strongly influenced by natural variability and the earth system response to existing greenhouse gases. In the end, the nature of the system is that a strong effect of policy, especially directed toward long-lived GHGs, will lag by 30 to 40 years its implementation. [ABSTRACT FROM AUTHOR]

• Wells-Dawson polyoxometalate containing Ni (II) counter-ion. • Magnetic studies of newly synthesized Wells-Dawson polyoxometalate. • Electrochemical studies of Wells-Dawson polyoxometalate. • Crystal structure of the new Wells-Dawson polyoxometalate. • Super capacitance of Wells-Dawson polyoxometalate. The monomeric Ni(II) containing Wells-Dawson polyoxometalate (POM) complex K 2 Rb 6 Ni 0.33 [P 2 W 18 O 62 ]Cl 2 ∼15·3H 2 O (K 2 Rb 6 –1) was synthesized, for the first time, by the reaction of [Ni 2 (µ-OH 2)(O 2 CCMe 3) 4 (HO 2 CCMe 3) 4 ] and K 6 [P 2 W 18 O 62 ]. 19H 2 O in an aqueous medium. The compound was characterized by elemental analysis, FTIR, TGA, and single-crystal XRD (trigonal, space group R 3 ¯ m , cell length a = 37.3660(4), b = 37.3660(4), c = 12.8340(2) Å, α = 90, β = 90, γ = 120°, V = 15,518.4(3), Z = 9) techniques. The oxidation state of Ni(II) was calculated through bond valence sum (BVS) calculations. The electrochemical study indicated the super capacitance behavior of POM K 2 Rb 6 –1, and its magnetic susceptibility study showed magnetization with a temperature range of 5 K-300 K. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: Adequate quantification of evapotranspiration (ET) is crucial to assess how climate change and land cover change (LCC) interact with the hydrological cycle of terrestrial ecosystems. The Mongolian Plateau plays a unique role in the global climate system due to its ecological vulnerability, high sensitivity to climate change and disturbances, and limited water resources. Here, we used a version of the Terrestrial Ecosystem Model that has been modified to use Penman–Monteith (PM) based algorithms to calculate ET. Comparison of site-level ET estimates from the modified model with ET measured at eddy covariance (EC) sites showed better agreement than ET estimates from the MODIS ET product, which overestimates ET during the winter months. The modified model was then used to simulate ET during the 21st century under six climate change scenarios by excluding/including climate-induced LCC. We found that regional annual ET varies from 188 to 286mmyr−1 across all scenarios, and that it increases between 0.11mmyr−2 and 0.55mmyr−2 during the 21st century. A spatial gradient of ET that increases from the southwest to the northeast is consistent in all scenarios. Regional ET in grasslands, boreal forests and semi-desert/deserts ranges from 242 to 374mmyr−1, 213 to 278mmyr−1 and 100 to 199mmyr−1, respectively; and the degree of the ET increase follows the order of grassland, semi-desert/desert, and boreal forest. Across the plateau, climate-induced LCC does not lead to a substantial change (<5%) in ET relative to a static land cover, suggesting that climate change is more important than LCC in determining regional ET. Furthermore, the differences between precipitation and ET suggest that the available water for human use (water availability) on the plateau will not change significantly during the 21st century. However, more water is available and less area is threatened by water shortage in the Business-As-Usual emission scenarios relative to level-one stabilization emission scenarios. [Copyright &y& Elsevier]

The growing need for risk-based assessments of impacts and adaptation to climate change calls for increased capability in climate projections: specifically, the quantification of the likelihood of regional outcomes and the representation of their uncertainty. Herein, the authors present a technique that extends the latitudinal projections of the 2D atmospheric model of the Massachusetts Institute of Technology (MIT) Integrated Global System Model (IGSM) by applying longitudinally resolved patterns from observations, and from climate model projections archived from exercises carried out for the Fourth Assessment Report (AR4) of the Intergovernmental Panel on Climate Change (IPCC). The method maps the IGSM zonal means across longitude using a set of transformation coefficients, and this approach is demonstrated in application to near-surface air temperature and precipitation, for which high-quality observational datasets and model simulations of climate change are available. The current climatology of the transformation coefficients is observationally based. To estimate how these coefficients may alter with climate, the authors characterize the climate models' spatial responses, relative to their zonal mean, from transient increases in trace-gas concentrations and then normalize these responses against their corresponding transient global temperature responses. This procedure allows for the construction of metaensembles of regional climate outcomes, combining the ensembles of the MIT IGSM-which produce global and latitudinal climate projections, with uncertainty, under different global climate policy scenarios-with regionally resolved patterns from the archived IPCC climate model projections. This hybridization of the climate model longitudinal projections with the global and latitudinal patterns projected by the IGSM can, in principle, be applied to any given state or flux variable that has the sufficient observational and model-based information. [ABSTRACT FROM AUTHOR]

We discuss a strategy for investigating the impacts of climate change on Earth's physical, biological and human resources and links to their socio-economic consequences. As examples, we consider effects on agriculture and human health. Progress requires a careful understanding of the chain of physical changes-global and regional temperature, precipitation, ocean acidification, polar ice melting. We relate those changes to other physical and biological variables that help people understand risks to factors relevant to their daily lives-crop yield, food prices, premature death, flooding or drought events, land use change. Finally, we investigate how societies may adapt, or not, to these changes and how the combination of measures to adapt or to live with losses will affect the economy. Valuation and assessment of market impacts can play an important role, but we must recognize the limits of efforts to value impacts where deep uncertainty does not allow a description of the causal chain of effects that can be described, much less assigned a likelihood. A mixed approach of valuing impacts, evaluating physical and biological effects, and working to better describe uncertainties in the earth system can contribute to the social dialogue needed to achieve consensus on the level and type of mitigation and adaptation actions. [ABSTRACT FROM AUTHOR]