Policy implications of warming permafrost

Permafrost is perennially frozen ground occurring in about 24% of the exposed land surface in the Northern Hemisphere. The distribution of permafrost is controlled by air temperature and, to a lesser extent, by snow depth, vegetation, orientation to the sun and soil properties. Any location with annual average air temperatures below freezing can potentially form permafrost. Snow is an effective insulator and modulates the effect of air temperature, resulting in permafrost temperatures up to 6°C higher than the local mean annual air temperature. Most of the current permafrost formed during or since the last ice age and can extend down to depths of more than 700 meters in parts of northern Siberia and Canada. Permafrost includes the contents of the ground before it was frozen, such as bedrock, gravel, silt and organic material. Permafrost often contains large lenses, layers and wedges of pure ice that grow over many years as a result of annual freezing and thawing of the surface soil laye

Cryomorphological topographies in the study of ice caves

Producción CientíficaThe current interest in ice caves requires that their varied manifestations be known as accurately as possible in view of their responses to a global change and also to their great potential as paleoenvironmental witnesses. This phenomenon has been known about for a long time but is still scarcely studied from the point of view of its cryological values and the evolution and distribution of many of their morphologies. For this, the development of cryomorphological topographies from traditional techniques to geodetic surveys with different tools, including terrestrial laser scanning, is one of the most current ways to characterize and quantify this type of cryospheric phenomena. It represents a new kind of periglacial cartography whose use is feasible in spite of the difficulties these environments present.Ministerio de Economía, Industria y Competitividad (project CGL2015-68144-R

Climate Change Impact Assessment for Surface Transportation in the Pacific Northwest and Alaska

WA-RD 772.

The Mysteries of Trend

Trends are ubiquitous in economic discourse, play a role in much economic theory, and have been intensively studied in econometrics over the last three decades. Yet the empirical economist, forecaster, and policy maker have little guidance from theory about the source and nature of trend behavior, even less guidance about practical formulations, and are heavily reliant on a limited class of stochastic trend, deterministic drift, and structural break models to use in applications. A vast econometric literature has emerged but the nature of trend remains elusive. In spite of being the dominant characteristic in much economic data, having a role in policy assessment that is often vital, and attracting intense academic and popular interest that extends well beyond the subject of economics, trends are little understood. This essay discusses some implications of these limitations, mentions some research opportunities, and briefly illustrates the extent of the difficulties in learning about trend phenomena even when the time series are far longer than those that are available in economics.Climate change, Etymology of trend, Paleoclimatology, Policy, Stochastic trend

Investigating the evolution of fractures in clay–based ceramics during repeated freeze-thawing cycles using micro X-ray computed tomography and image analysis

Acknowledgements Ignazio Allegretta was supported by a research grant on the project PON R&I – Progetto AIM1809249 – attivitá 1, linea 1. Data Availability The raw/processed data required to reproduce these findings cannot be shared at this time as they include more than 4TB of raw micro-tomographic data. However, for those researchers interested in analysing this dataset, tomographic data will be made available upon request by contacting the Dr. Carlo Porfido (e-mail: [email protected]). The FracPaQ toolbox, used for image analysis, is freely available to download from the following addresses: http://fracpaq.com/index.html.Peer reviewedPostprin

GPU-based 3D iceball modeling for fast cryoablation simulation and planning

Purpose The elimination of abdominal tumors by percutaneous cryoablation has been shown to be an effective and less invasive alternative to open surgery. Cryoablation destroys malignant cells by freezing them with one or more cryoprobes inserted into the tumor through the skin. Alternating cycles of freezing and thawing produce an enveloping iceball that causes the tumor necrosis. Planning such a procedure is difficult and time-consuming, as it is necessary to plan the number and cryoprobe locations and predict the iceball shape which is also influenced by the presence of heating sources, e.g., major blood vessels and warm saline solution, injected to protect surrounding structures from the cold. Methods This paper describes a method for fast GPU-based iceball modeling based on the simulation of thermal propagation in the tissue. Our algorithm solves the heat equation within a cube around the cryoprobes tips and accounts for the presence of heating sources around the iceball. Results Experimental results of two studies have been obtained: an ex vivo warm gel setup and simulation on five retrospective patient cases of kidney tumors cryoablation with various levels of complexity of the vascular structure and warm saline solution around the tumor tissue. The experiments have been conducted in various conditions of cube size and algorithm implementations. Results show that it is possible to obtain an accurate result within seconds. Conclusion The promising results indicate that our method yields accurate iceball shape predictions in a short time and is suitable for surgical planning

Protocol for large scale whole blood immune monitoring by mass cytometry and Cyto Quality Pipeline

Support has been received (PI: M.E.A.) from the IMI2-JU project GA No 831434 (3TR) and IMI-JU project GA No 115565 (PRECISESADS). P.R. has received support from EMBO (7966) and from Consejería de Salud de Junta de Andalucía (EF-0091-2018). C.M. acknowledges funding from Programa Nicolas Monardes (C2-0002-2019). J.M.M. is funded by European Union-NextGenerationEU, Ministry of Universities (Spain’s Government) and the Recovery, Transformation and Resilience Plan. These results form a part of the P.R. PhD thesis in Biomedicine at the University of Granada. We are grateful to Olivia Santiago and Jose Diaz Cuéllar for technical support as a Core facility in Genyo research center. Also, we would like to express our gratitude to the donors. The figures in this paper were created with BioRender.comMass cytometry (MC) is a powerful large-scale immune monitoring technology. To maximize MC data quality, we present a protocol for whole blood analysis together with an R package, Cyto Quality Pipeline (CytoQP), which minimizes the experimental artifacts and batch effects to ensure data reproducibility. We describe the steps to stimulate, fix, and freeze blood samples before acquisition to make them suitable for retrospective studies. We then detail the use of bar-coding and reference samples to facilitate multicenter and multi-batch experiments.For complete details on the use and execution of this protocol, please refer to Rybakowska et al. (2021a) and (2021b).IMI2-JU project GA 831434IMI-JUproject GA 115565European Molecular Biology Organization (EMBO) 7966Junta de Andalucía EF-0091-2018Programa Nicolás Monardes C2-0002-2019European Union-NextGenerationEUMinistry of Universities (Spain's Government) and the Recovery, Transformation and Resilience Pla

Planet Four: Terrains - Discovery of Araneiforms Outside of the South Polar Layered Deposits

We present the results of a systematic mapping of seasonally sculpted terrains on the South Polar region of Mars with the Planet Four: Terrains (P4T) online citizen science project. P4T enlists members of the general public to visually identify features in the publicly released Mars Reconnaissance Orbiter CTX images. In particular, P4T volunteers are asked to identify: 1) araneiforms (including features with a central pit and radiating channels known as 'spiders'); 2) erosional depressions, troughs, mesas, ridges, and quasi-circular pits characteristic of the South Polar Residual Cap (SPRC) which we collectively refer to as 'Swiss cheese terrain', and 3) craters. In this work we present the distributions of our high confidence classic spider araneiforms and Swiss cheese terrain identifications. We find no locations within our high confidence spider sample that also have confident Swiss cheese terrain identifications. Previously spiders were reported as being confined to the South Polar Layered Deposits (SPLD). Our work has provided the first identification of spiders at locations outside of the SPLD, confirmed with high resolution HiRISE imaging. We find araneiforms on the Amazonian and Hesperian polar units and the Early Noachian highland units, with 75% of the identified araneiform locations in our high confidence sample residing on the SPLD. With our current coverage, we cannot confirm whether these are the only geologic units conducive to araneiform formation on the Martian South Polar region. Our results are consistent with the current CO2 jet formation scenario with the process exploiting weaknesses in the surface below the seasonal CO2 ice sheet to carve araneiform channels into the regolith over many seasons. These new regions serve as additional probes of the conditions required for channel creation in the CO2 jet process. (Abridged)Comment: accepted to Icarus - Supplemental data files are available at https://www.zooniverse.org/projects/mschwamb/planet-four-terrains/about/results - Icarus print version available at http://www.sciencedirect.com/science/article/pii/S001910351730055

Arginine, a Key Residue for the Enhancing Ability of an Antifreeze Protein of the Beetle Dendroides canadensis

Antifreeze proteins (AFPs) can produce a difference between the nonequilibrium freezing point and the melting point, termed thermal hysteresis (TH). The TH activity of an antifreeze protein (AFP) depends on the specific AFP and its concentration as well as the presence of cosolutes including low molecular mass solutes and/or proteins. We recently identified series of carboxylates and polyols as efficient enhancers for an AFP from the beetle Dendroides canadensis. In this study, we chemically modified DAFP-1 using the arginine-specific reagent 1,2-cyclohexanedione. We demonstrated that 1,2-cyclohexanedione specifically modifies one arginine residue and the modified DAFP-1 loses its enhancing ability completely or partially in the presence of previously identified enhancers. The stronger the enhancement ability of the enhancer on the native DAFP-1, the stronger the enhancement effect of the enhancer on the modified DAFP-1. The weaker enhancers (e.g., glycerol) completely lose their enhancement effect on the modified DAFP-1 due to their inability to compete with 1,2-cyclohexanedione for the arginine residue. Regeneration of the arginine residue using hydroxylamine fully restored the enhancing ability of DAFP-1. These studies indicated that an arginine residue is critical for the enhancing ability of DAFP-1 and the guanidinium group of the arginine residue is important for its interaction with the enhancers, where the general mechanism of arginine−ligand interaction is borne. This work may initiate a complete mechanistic study of the enhancement effect in AFPs

Ice wedge polygon stability on steep slopes in West Greenland related to temperature and moisture dynamics of the active layer

Ice wedge polygons on steep slopes have generally been described as being covered by periglacial sediments and, typically, the active layer on slopes becomes mobile during thaw periods, which can lead to solifluction. In West Greenland close to the ice margin, however, the active layer and ice wedge polygons are stable despite their occurrence on steep slopes with inclinations of ≥30°. We conducted a soil survey (including sampling for soil analyses and radiocarbon dating) in the Umimmalissuaq valley and installed a field station ~4 km east of the current ice margin to monitor soil temperature and water tension at depths of 10, 20 and 35 cm of the active layer on a steep, north-facing slope in the middle of an ice wedge polygon from 2009 to 2015. Thawing and freezing periods lasted between 2 and 3 months and the active layer was usually completely frozen from November to April. We observed simultaneous and complete water saturation at all three depths of the active layer in one summer for 1 day. The amount of water in the active layer apparently was not enough to trigger solifluction during the summer thaw, even at slope inclinations above 30°. In addition, the dense shrub tundra absorbs most of the water during periods between thawing and freezing, which further stabilizes the slope. This process, together with the dry and continental climate caused by katabatic winds combined with no or limited frost heave, plays a crucial role in determining the stability of these slopes and can explain the presence of large-scale stable ice wedge polygon networks in organic matter-rich permafrost, which is about 5,000 years old. This study underlines the importance of soil hydrodynamics and local climate regime for landscape stability and differing intensities of solifluction processes in areas with strong geomorphological gradients and rising air temperatures