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This study investigates the climatic response of the Arctic to key factors that could shape future climate scenarios: significantly reduced ice sheets, changes in vegetation, and elevated CO2 levels. Using the EC-Earth3.3 Earth system model (ESM), we explore the effects of these forcings under conditions reminiscent of the mid-Pliocene, a key reference for potential future warm climates. Our results reveal that the Arctic climate response varies significantly with different CO2 levels, primarily due to feedbacks involving sea ice and surface albedo. The effects of the reduced ice sheet are, in a pre-industrial CO2 environment (280 ppm), an Arctic warming of 2.4°C. This is driven by substantial sea ice loss in the Barents Sea, which reduces surface albedo. Surprisingly, at 400 ppm CO2, Arctic warming incurred from the ice sheet reduction is lower than expected, at 1.9°C, because sea ice loss is less pronounced compared to pre-industrial conditions, leading to smaller albedo changes. At 560 ppm, the warming is more substantial (2.9°C) but still less than expected, largely due to the already reduced sea-ice extent at this high CO2 level. Vegetation changes further modulate Arctic climate dynamics. At 400 ppm CO2, the expansion of needleleaf evergreen trees decreases surface albedo, adding an additional 0.5°C of warming. However, at 560 ppm CO2, the warming effect of vegetation growth was muted (0.3°C) due to the development of a more diverse canopy with brighter deciduous species, which mitigates the albedo-driven warming. Our findings underscore the complex interplay between CO2 levels, sea ice, and vegetation in determining in Arctic climate dynamics. They highlight that the importance of maintaining CO2 levels at or below 400 ppm to moderate Arctic warming effectively. This study emphasizes the value of integrating paleoclimate insights into future climate projections and underscores the need for a more detailed examination of feedback mechanisms to enhance the robustness of climate models.

Abstract The impact of mid‐Pliocene boundary conditions on Afro‐Asian summer monsoon (AfroASM) rainfall is examined using the fully coupled Earth System Model EC‐Earth3‐LR. Our focus lies on the effects of varying CO2 concentration, diminished ice sheets and vegetation dynamics. We find that the enhanced AfroASM rainfall is predominantly caused by the “warmer‐gets‐wetter” mechanism due to elevated CO2 levels. Additionally, the ice sheet, similar in size to that of the mid‐Pliocene era, creates several indirect effects. These include sea ice‐albedo feedback and inter‐hemispheric atmosphere energy transport. Such influences result in the southward shift of Hadley circulation and formation of Pacific‐Japan pattern, leading to reduced rainfall in North African and South Asian monsoon regions but increased rainfall in East Asian monsoon region. Interestingly, while dynamic vegetation feedback has a minimal direct effect on AfroASM rainfall, it significantly influences rainfall in the mid‐high latitudes of the North Hemisphere by enhancing water vapor feedback.

Background:. Breast cancer-related lymphedema impacts 30% to 47% of women who undergo axillary lymph node dissection (ALND). Studies evaluating the effectiveness of prophylactic lymphovenous bypass (LVB) at the time of ALND have had small patient populations and/or short follow-up. The aim of this study is to quantitatively and qualitatively evaluate prophylactic LVB in patients with breast cancer. Methods:. A retrospective review of patients who underwent ALND from 2018 to 2022 was performed. Patients were divided into cohorts based on whether they underwent prophylactic LVB at the time of ALND. Primary outcomes included 30-day complications and lymphedema. Lymphedema was quantitatively evaluated by bioimpedance analysis, with L-dex scores >7.1 indicating lymphedema. Results:. One-hundred five patients were identified. Sixty-four patients (61.0%) underwent ALND and 41 patients (39.0%) underwent ALND+LVB. Postoperative complications were similar between the cohorts. At a median follow-up of 13.3 months, lymphedema occurred significantly higher in the ALND only group compared with ALND+LVB group (50.0% vs 12.2%; P < 0.001). ALND without LVB was an independent risk factor for lymphedema development (odds ratio, 4.82; P = 0.003). Conclusions:. Prophylactic LVB decreases lymphedema and is not associated with increased postoperative complications. A multidisciplinary team approach is imperative to decrease lymphedema development in this patient population.

Amassing the available solar energy over the Sahara desert, through the installation of a large-scale solar farm, would satisfy the world’s current electricity needs. However, such land use changes may affect the global carbon cycle, possibly offsetting mitigation efforts. Here a fully coupled Earth System model EC-Earth was used to investigate the impact of a Saharan solar farm on the terrestrial carbon cycle, simulated with prescribed reduced surface albedo approximating the albedo effect of photovoltaic solar panels over the Sahara desert. The resulting changes to the carbon cycle were an enhancement of the carbon sink across Northern Africa, particularly around the Sahel but a simultaneous weakening of the carbon sink in the Amazon basin. This is observed through spatial pattern changes to the values of net biome production (NBP), more evident during Northern Hemisphere summer season. NBP changes are contributed by competing responses in the net primary production and heterotrophic respiration rates. These changes to carbon exchange correspond to a wetter and warmer climate occurring in Northern Africa and a drier and warmer climate in the Amazon, with stronger driving effects of precipitation. Due to these coupled responses and complex teleconnections, thorough investigation of remote impacts of solar farms are needed to avoid unintended consequences on the terrestrial carbon cycle.

The Indian Summer Monsoon (ISM) plays a vital role in the livelihoods and economy of those living on the Indian subcontinent, including the small, mountainous country of Bhutan. The ISM fluctuates over varying temporal scales and its variability is related to many internal and external factors including the El Niño Southern Oscillation (ENSO) and the Indian Ocean Dipole (IOD). In 2015, a Super El Niño occurred in the tropical Pacific alongside a positive IOD in the Indian Ocean and was followed in 2016 by a simultaneous La Niña and negative IOD. These events had worldwide repercussions. However, it is unclear how the ISM was affected during this time, both at a regional scale over the whole ISM area and at a local scale over Bhutan. First, an evaluation of data products comparing ERA5 reanalysis, TRMM and GPM satellite, and GPCC precipitation products against weather station measurements from Bhutan, indicated that ERA5 reanalysis was suitable to investigate ISM change in these two years. The reanalysis datasets showed that there was disruption to the ISM during this period, with a late onset of the monsoon in 2015, a shifted monsoon flow in July 2015 and in August 2016, and a late withdrawal in 2016. However, this resulted in neither a monsoon surplus nor a deficit across both years but instead large spatial-temporal variability. It is possible to attribute some of the regional scale changes to the ENSO and IOD events, but the expected impact of a simultaneous ENSO and IOD events are not recognizable. It is likely that 2015/16 monsoon disruption was driven by a combination of factors alongside ENSO and the IOD, including varying boundary conditions, the Pacific Decadal Oscillation, the Atlantic Multi-decadal Oscillation, and more. At a local scale, the intricate topography and orographic processes ongoing within Bhutan further amplified or dampened the already altered ISM.

Irregular climate events frequently occur in Southeast Asia due to the numerous climate patterns combining. Thailand sits at the confluence of these interactions, and consequently experiences major hydrological events, such as droughts. Proxy data, speleothem records, lake sediment sequences and tree ring chronologies were used to reconstruct paleo drought conditions. These trends were compared with modelled and historic El Niño Southern Oscillation (ENSO) data to assess if the ENSO climate phenomena is causing droughts in Thailand. Drought periods were found to occur both during El Niño events and ENSO neutral conditions. This indicates droughts are not a product of one climate pattern, but likely the result of numerous patterns interacting. There is uncertainty regarding how climate patterns will evolve under climate change, but changes in amplitude and variability could potentially lead to more frequent and wider reaching hydrological disasters. It is vital that policies are implemented to cope with the resulting social and economic repercussions, including diversification of crops and reorganisation of water consumption behaviour in Thailand.

Sleep-wake disturbances frequently present in Veterans with mild traumatic brain injury (mTBI). These TBI-related sleep impairments confer significant burden and commonly exacerbate other functional impairments. Therapies to improve sleep following mTBI are limited and studies in Veterans are even more scarce. In our previous pilot work, morning bright light therapy (MBLT) was found to be a feasible behavioral sleep intervention in Veterans with a history of mTBI; however, this was single-arm, open-label, and non-randomized, and therefore was not intended to establish efficacy. The present study, LION (light vs ion therapy) extends this preliminary work as a fully powered, sham-controlled, participant-masked randomized controlled trial (NCT03968874), implemented as fully remote within the VA (target n = 120 complete). Randomization at 2:1 allocation ratio to: 1) active: MBLT (n = 80), and 2) sham: deactivated negative ion generator (n = 40); each with identical engagement parameters (60-min duration; within 2-hrs of waking; daily over 28-day duration). Participant masking via deception balanced expectancy assumptions across arms. Outcome measures were assessed following a 14-day baseline (pre-intervention), following 28-days of device engagement (post-intervention), and 28-days after the post-intervention assessment (follow-up). Primary outcomes were sleep measures, including continuous wrist-based actigraphy, self-report, and daily sleep dairy entries. Secondary/exploratory outcomes included cognition, mood, quality of life, circadian rhythm via dim light melatonin onset, and biofluid-based biomarkers. Participant drop out occurred in 85%, collectively establishing feasibility and acceptability for MBLT in Veterans with mTBI.

There is a growing body of evidence that links increased social capital to minority student success in college. This paper seeks to expand specifically on the graduate experience of underrepresented minorities (URM) at a Hispanic Serving Institution (HSI) using the social capital framework. In a cross-sectional survey, 198 graduate students retrospectively considered the role of institutional resources and agents in their success towards graduation. Data revealed that motivational factors such as a sense of personal achievement, family support, peer support, career promotion, supportive faculty, program satisfaction, and faculty mentor played critical roles in the success of graduate students at HSI. Specifically, Latino students are more likely to report that faculty mentors played a significant role in their success compared to their non-Latino peers χ2(1, N = 195) = 5.33, p = 0.02. Latinos/as were also more likely to use writing support services than their non-Latino/a peers χ2(2, N = 190) = 7.59, p = 0.02. By identifying and increasing access to institutional resources and agents, underrepresented minorities in post-baccalaureate programs may encounter less barriers to graduate degree success.