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GEWEX Quarterly, Vol. 33, No. 1
(International GEWEX Project Office, 2023-02) Zeng, Xubin; Polcher, Jan; Stephens, Graeme; van Oevelen, Peter; Attig Bahar, Faten; Koren, Gerbrand; Rabanal, Valentina; YESS Executive Committee; Byrnes, Danyka; Becker, Paige; Kollet, Stefan; Condon, Laura; Xue, Yongkang; Boone, Aaron; Yao, Tandong; Diallo, Ismaila; Lau, William K.M.; Nayak, Hara; LS4P team; Pomeroy, John; Moreno, Ignacio López; McPhee, James; DeBeer, Chris; Boutle, Ian; Lakatos, Monika; Horváth, Csaba; Ukazu, Bethel Ugochukwu; Wasswa, Peter; Lamptey, Patrick Nii Lante; Zaroug, Modathir
This issue of GEWEX Quarterly contains the articles on the following: a commentary reviewing the 30 Years of GEWEX BAMS paper; new GEWEX Panel and SSG members; YESS involvement in PAUWES, SRI Congress 2023, and the WCRP OSC; AGU H3S’s planning for new seminar series, 2023 AGU Fall Meeting events, and a fresh new look for its website; a new GEWEX initiative to improve groundwater modeling; LS4P examines the remote effect of Tibetan Plateau spring temperature and identifies high mountain land temperature as a possible first order source of S2S precipitation predictability (Phase I Highlights and Phase II Initiation); INARCH strives to increase insights into alpine cold regions hydrological processes; the Demistify project uses single-column model and large-eddy simulation intercomparisons to delve into radiation fog; PannEx holds 6th meeting to work towards a better understanding of Earth system components and their interactions in the Pannonian Basin; and a workshop on the role of early career researchers in contributing to Earth observations and geospatial science in Africa examines data access and availability, technology and technique handling, and collaboration.
An Integrative Approach to Evaluating Metabolic Indicators in Maned Wolves (Chrysocyon Brachyurus)
(2024-07-26) Jane Braswell; Hunt, Dr. Kathleen
Integrated datasets of physiology and behavior are critical to determining the impact of environmental threats on animal health. Continued advancements in biologging technology aid this effort; however, additional techniques, such as endocrinology, can help contextualize findings. Maned wolves (Chrysocyon brachyurus) experience broad-scale landscape alteration, presenting a need for reliable indices of metabolic health. I tested a protocol for long-term monitoring of metabolic health in free-ranging wildlife by integrating biologging and analysis of hair triiodothyronine (T3), a form of thyroid hormone, using captive maned wolves as a model. Hair samples were collected approximately every three months for just over one year from maned wolves (n=8) implanted with Reveal LINQ™ (Medtronic Inc., Minneapolis, MN) biologgers at the Smithsonian National Zoo and Conservation Biology Institute in Front Royal, Virginia, USA. Daily average heart rate (HR) and heart rate variability (HRV), and daily total activity were calculated from raw biologger data. T3 was measured in guard hair via a T3 enzyme-linked immunosorbent assay (Arbor Assays, MI), which passed analytical validations for maned wolf hair extract. To evaluate the feasibility of integrating these measures, I tested the impact of various determinants of metabolism (e.g. season, ambient temperature, activity, food intake, and body weight) on HR, HRV, and hair T3. I detected seasonal patterns in all metabolic indicators. Notably, HR increased and HRV decreased in winter, indicating increased activation of the sympathetic nervous system, and by inference, increased metabolic activity. Variation in HR and HRV was primarily explained by ambient temperature. Contrary to predictions, hair T3 was greatest in summer and lowest in winter and was positively impacted by ambient temperature. This may indicate that increased metabolic activity in winter was triggered by types of stressors that are not reflected in circulating thyroid hormone concentrations. Alternatively, apparent hormone concentrations in hair may reflect different time periods than expected or may not reflect plasma concentrations consistently. Ultimately, I demonstrate the feasibility of combining biologging metrics with analysis of T3 in hair, but also highlight the need for further investigation of hair T3 as a potential proxy of plasma T3, and of T3, in turn, as an indicator of energetic state. Because hormones are incorporated into hair as it grows, may be a particularly valuable sample type for retrospective analysis of animals’ physiological state over time. Thus, this integrated assessment of biologging parameters and endocrinology shows promise for application in situ, in combination with other ecological assessments, as the field aims to understand how free-ranging maned wolves’ meet the energetic demands of altered landscapes.
Transit Depth Variations of Young Warm Neptune AU Mic b
(2024-07-17) Aldridge, Kyle; Plavchan, Dr. Peter
We present a study of transit depth variations of AU Mic b. The 33 transit observations used in this study were made by nine telescopes and were previously used to investigate the transit timing variations of the AU Mic planetary system. We modeled the light curves with EXOFASTv2, allowing for independent constraints on planetary parameters and allowed for each transit to have an independent transit depth. We then constructed a broadband transmission spectrum. Then, we modeled AU Mic b’s atmospheric spectrum using NASA’s Planetary Spectrum Generator (PSG). AU Mic b’s 7-4 spin orbit resonance with its host star allowed us to probe transit depth at one of four possible stellar longitude ranges per transit number. At 0.7865 microns, as observed by TESS, AU Mic b has an average Rp/R⋆ of 0.05048+0.00073−0.00088, while at 4.5 microns, as observed by Spitzer, AU Mic b has an average Rp/R⋆ of 0.04552+0.00092−0.00097. Our model atmospheres, with an average Rp/R⋆ of 0.05111 at 4.5 microns, indicate AU Mic b should be larger if unaffected by noise or stellar activity. Our investigation of transit depth per stellar longitude range shows no obvious effect of spot modulation. Given these results, and the previous studies on the young warm Neptune K2-33b, that resulted in the rejection of starspots and photochemical hazes, we conclude circumplanetary material is likely to exist around AU Mic b. If AU Mic b has circumplanetary material, this would present the opportunity to study it at an early age and close distance. This would be useful because circumplanetary material is challenging to observe.
Maijuna Perspectives on the Establishment and Co-Management of the Maijuna-Kichwa Regional Conservation Area (MKRCA)
(2024-07-26) Cano, Natalia Arcos; Gilmore, Michael
Growing awareness of the critical role Indigenous People and Local Communities (IPLC) play in biodiversity conservation has underscored the need to shift conservation practices towards empowering IPLCs, supporting their land rights, traditional practices, and facilitating their political involvement. Despite IPLCs governing over 32% of global land, historically, these communities have faced systemic marginalization and violence in the name of conservation. In response, international calls to action and policies have aimed to enhance IPLC participation in environmental governance through mechanisms like co-management. Adaptive Co-management (ACM) emerges as a promising approach, combining adaptive management’s flexibility with co-management’s collaborative principles. This study evaluates the ACM framework within the Maijuna-Kichwa Regional Conservation Area (MKRCA) in the Peruvian Amazon, established to protect the ancestral lands and biocultural resources of the Maijuna and Kichwa communities. Using Community-Based Participatory Research (CBPR) and appreciative action inquiry, we conducted interviews with 36 community members to assess their perspectives on the MKRCA’s co-management. Findings reveal significant improvements in resource abundance and community safety but also highlight issues with governmental support, communication, and equitable participation. The study emphasizes the need for continuous evaluation and enhanced stakeholder engagement to optimize ACM’s effectiveness, offering culturally responsive recommendations to strengthen the MKRCA’s management and achieve its conservation objectives.
Examining the Emergence of Per- and Polyfluoroalkyl Substances as a Federal Policy Topic
(2024-05-10) Dobry, Charlotte; Kim, Younsung
Per- and polyfluoroalkyl substances (PFAS), colloquially referred to as “forever chemicals”, include approximately 15,000 chemicals. These chemicals have applications in commercial, household, and industrial settings, and have been detected nearly everywhere on earth. While data about PFAS’ environmental persistence and human health risks came to the attention of the U.S. Environmental Protection Agency around the turn of the century, protective policies regarding PFAS use and acceptable exposure levels has been slow to evolve. Using John J. Kingdon’s multiple streams framework as a theoretical lens, this study reviewed Congressional bills and surveyed policy community stakeholders to analyze the factors important in PFAS’ emergence as a policy agenda topic. We found that support from policy entrepreneurs as information brokers was crucial in advancing policy, whether inside or outside of government. Additionally, attorneys, scientists, and community organizers were identified as key individuals in defining PFAS as a problem and raising awareness on a larger scale. These findings contribute to better understanding how environmental topics such as emerging contaminants, where there is a period of information gathering necessary to inform policy development, may successfully rise as agenda topics.