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Despite tectonic conditions and atmospheric CO2 levels (pCO2) similar to those of present-day, geological reconstructions from the mid-Pliocene (3.3-3.0 Ma) document high lake levels in the Sahel and mesic conditions in subtropical Eurasia, suggesting drastic reorganizations of subtropical terrestrial hydroclimate during this interval. Here, using a compilation of proxy data and multi-model paleoclimate simulations, we show that the mid-Pliocene hydroclimate state is not driven by direct CO2 radiative forcing but by a loss of northern high-latitude ice sheets and continental greening. These ice sheet and vegetation changes are long-term Earth system feedbacks to elevated pCO2. Further, the moist conditions in the Sahel and subtropical Eurasia during the mid-Pliocene are a product of enhanced tropospheric humidity and a stationary wave response to the surface warming pattern, which varies strongly with land cover changes. These findings highlight the potential for amplified terrestrial hydroclimate responses over long timescales to a sustained CO2 forcing.

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In this study, an assessment is made of the trends of actual evapotranspiration (AE) over China under global warming from an ensemble of the following data sets: National Centers for Environmental Prediction‐National Center for Atmospheric Research reanalysis I, National Centers for Environmental Prediction‐Department of Energy reanalysis II, Modern‐Era Retrospective Analysis for Research and Applications (MERRA), MERRA Version 2, European Centre for Medium‐Range Weather Forecasts Interim Re‐Analysis, and Japanese 55‐year Reanalysis. For China as a whole, annual AE exhibited a significant increasing trend from 1979 to 2015, and the rate of increase was highest in autumn and lowest in summer. By subdividing China into six climatic regions using the aridity index, significant increasing trends in AE are found over the hyperarid, arid, and humid regions, but slightly decrease over the dry subhumid and subhumid regions. For the hyperarid and arid regions, the increases in potential evapotranspiration and the water supply from melting glaciers due to both climate warming and human activities might be the main contributors to the AE increases. An increase in potential evapotranspiration driven by global warming is the main cause of the increased AE over the humid region. On a seasonal basis, most AE over China occurs in summer. However, increasing AE trends have been observed mainly in autumn and winter, and the increase is statistically significant over all of China's six climatic regions in winter. In view of data availability, reanalyses are compared with the results from Mezentsev‐Choudhury‐Yang equation (AE_Budyko). The correlations between individual reanalyses and AE_Budyko tend to be higher over the arid region.

This paper reports an extremely long spin relaxation time of optically polarized light-emitting states at room temperature in quasi-2D perovskites [(PEA)2(MA)4Pb5Br16 with n = 5], when the long-range orbit–orbit interaction between excited states is developed through orbital polarization. Our studies found that the quasi-2D perovskite [(PEA)2(MA)4Pb5Br16 with n = 5] demonstrates a long-range orbit–orbit interaction between excited states to conserve the spins of optically polarized light-emitting states, identified by the positive change on photoluminescence intensity (+ΔPL) in steady state upon switching the photoexcitation from linear to circular polarization. Meanwhile, the PL circular polarization (σ+σ+ – σ+σ–) can maintain in nanosecond under fixed photoexcitation (σ+). In contrast, the 2D/3D mixed perovskite (n > 5) shows a short-range orbit–orbit interaction between excited states through orbital magnetic dipoles, identified by the −ΔPL by switching from linear to circular photoexcitation. At the same time, the spin lifetime of light-emitting states becomes undetectable.

Submicron metallic lateral spin valves are fabricated with AlO x tunnel junctions as spin injection and detection barriers. The spin polarization is estimated to be ϳ20%, determined by both Hanle effect and variations of device dimensions. The polarization is maintained at a large dc injection current density Ͼ2 ϫ 10 6 A / cm 2 . Both the spin polarization and spin diffusion length are weakly temperature dependent.