A number of past studies have attempted to place modern Atlantic TC activity in a longer-term context using regional proxy evidence of past landfalling Atlantic hurricane activity [6][7][8] . Some studies 4 have sought to infer past changes in activity from plausible local conditioning factors such as wind strength and Sea Surface Temperature (SST), though the interpretations of these studies have been contested 5 . Qualitative comparisons between paleo-hurricane reconstructions appear to show some temporal coherence 8-9 .However, no past studies have attempted to synthesize multiple records from distinct regions into a basin-integrated reconstruction of Atlantic hurricane activity. Moreover, no past studies have sought to quantitatively relate estimated variations in hurricane or TC activity to reconstructions of the key large-scale climate factors known to have a 3 significant influence on modern Atlantic TC activity. Here we produce an empirical record of past landfalling Atlantic hurricane activity by combining information from multiple sedimentary records of TC-induced overwash. Further we compare these resulting estimates to independent statistical model predictions of past TC activity driven by proxy-based large-scale climate reconstructions.Sediment-based overwash reconstructions of TC landfall are limited in number, but span a wide geographic area across the North Atlantic basin impacted by hurricanes. Our compilation includes (Figure 1) a site from the Caribbean (Vieques, PR 6,9,10 ), one from the U.S. Gulf Coast 11 , one from the southeastern U.S. coast 8 , three from the mid-Atlantic coast (one from New York 9 and two from New Jersey 12,13 ) and two from southeastern New England (one from Rhode Island 14 and another from Massachusetts 15 ) yielding 5 distinct regional series. We obtained a probabilistic estimate of past basin-wide landfalling hurricane activity using an appropriately weighted combination of the information from these 5 regional series, and incorporating radiocarbon age model uncertainties.An independent estimate of past tropical cyclone activity was obtained using a statistical model for Atlantic TC counts. This previously developed and validated 16,3 statistical model conditions annual Atlantic TC counts on three key large-scale climate state variables tied to historical variations in Atlantic TC counts: (i) Sea Surface Temperature (SST) over the main development region (MDR) for tropical Atlantic TCs, which reflects favorability of the local thermodynamic environment, (ii) the El Niño/Southern Oscillation (ENSO) which influences the amount of (unfavorable) vertical wind shear, and (iii) the North Atlantic Oscillation (NAO) phenomena which affects the tracking of storms (which influences how favorable an environment they 4 encounter). The statistical model was driven by proxy-based reconstructions 17,18 of these three state variables (Figure 2), yielding a predicted history of Atlantic TC counts for past centuries We compared the sediment-based record against the above statistical e...

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It has been a goal to create artificial evaporators that have highly efficient solar steam generation (SSG) performance under omnidirectional illumination to solve the global drinking water crisis. Although some evaporators with high evaporation rates and efficiencies have been reported, their inefficient performance under oblique illumination conditions remain to be overcome. Pinecones, with their delicate transpiration channels, photo‐thermal moisture‐sensitive deployable structure, and 3D Fibonacci helically‐arranged scales, inspire the design of this efficient evaporator under omnidirectional illumination. Herein, ultra‐black pinecone (UBP) with multi‐branched, arterially porous, and hierarchical structures shows excellent SSG performance under omnidirectional illumination. UBP achieves a high evaporation rate and efficiency of 1.86 kg m−2 h−1 and 97.85% respectively, under one sun illumination. The SSG performance under oblique incidence conditions of UBP are not degraded but improved (2.194 g h−1 under incident angle of 90°) because the UBP can recover reflection and radiation energy losses, avoid cosine energy losses, and absorb heat from the warm environment. The UBP also exhibits high evaporation rate in real weather and good durability and salt resistance in concentrated brine, which ensures its great potential applications in wastewater treatment and solar desalination.

Bi2Te3-based compounds are important near room temperature thermoelectric materials with commercial applications in thermoelectric modules. However, new routes leading to improved thermoelectric performance are highly desirable. Incorporation of superparamagnetic nanoparticles was recently proposed as a means to promote the thermoelectric properties of materials, but its feasibility has rarely been examined in mainstream thermoelectric materials. In this study, high quality single-crystalline Bi2Te2.7Se0.3 nanoplates and Ni nanoparticles were successfully synthesized by solvothermal and thermal decomposition methods, respectively. Bulk nanocomposites consisting of Bi2Te2.7Se0.3 nanoplates and superparamagnetic Ni nanoparticles were prepared by spark plasma sintering. It was found that incorporation of Ni nanoparticles simultaneously increased the carrier concentration and provided additional scattering centers, which resulted in enlarged electric conductivities and Seebeck coefficients. The greatly improved ZT was achieved due to the increase in power factor. Spark plasma sintered bulk nanocomposites of Bi2Te2.7Se0.3 nanoplates incorporated by 0.4 mol %Ni nanoparticles (in molar ratio) showed a figure-of-merit ZT of 0.66 at 425 K, equivalent to 43% increase when compared to pure Bi2Te2.7Se0.3 nanoplates. The results revealed that incorporation of magnetic nanoparticles could be an effective approach for promoting the thermoelectric performance of conventional semiconductors.

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