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In the context of global climate change, heatwaves are becoming increasingly significant because of the adverse impacts on human health and ecosystems. However, the quantification of heatwaves relies on different temperature metrics, and little is known about how the different types of heatwaves are affected by soil moisture. Using a set of observational datasets during the period 1981–2020, this study investigates the characteristics of warm-season heatwaves over the contiguous United States (CONUS) derived from three different temperature metrics (temperature, wet-bulb temperature, and equivalent temperature), and examines how different types of heatwaves are associated with soil moisture. Increasing trends of all types of heatwaves are observed in most parts of CONUS except for the central US, posing potential risks to human health. Due to limited evaporative cooling over dry soil, there is a substantial negative relationship between soil moisture and temperature-only heatwaves across the CONUS. Meanwhile, in some regions of the western and central CONUS, there is an evident positive relationship between soil moisture and humidity-included heatwaves, which represent the combined effects of temperature and humidity. The event-based analysis in Nebraska emphasizes that temperature-only heatwaves occur over relatively dry soil conditions, while humid heatwaves tend to occur over somewhat wet soil. Our results highlight the importance of considering different types of heatwaves and their relationship with soil moisture from the land-atmosphere coupling perspective, offering valuable insights for local and regional climate planning and mitigation.

The glacier mass balance is an important variable to describe the climate system and is used for various applications like water resource management or runoff modelling. The direct or glaciological method and the geodetic method are the standard methods to quantify glacier mass changes, and both methods are an integral part of international glacier monitoring strategies. In 2011, we established two glacier mass-balance programmes on Yala and Rikha Samba glaciers in the Nepal Himalaya. Here we present the methods and data of the directly measured annual mass balances for the first six mass-balance years for both glaciers from 2011/2012 to 2016/2017. For Yala Glacier we additionally present the directly measured seasonal mass balance from 2011 to 2017, as well as the mass balance from 2000 to 2012 obtained with the geodetic method. In addition, we analysed glacier length changes for both glaciers. The directly measured average annual mass-balance rates of Yala and Rikha Samba glaciers are −0.80 ± 0.28 and −0.39 ± 0.32 m w.e. a−1, respectively, from 2011 to 2017. The geodetically measured annual mass-balance rate of Yala Glacier based on digital elevation models from 2000 and 2012 is −0.74 ± 0.53 m w.e. The cumulative mass loss for the period 2011 to 2017 for Yala and Rikha Samba glaciers is −4.80 ± 0.69 and −2.34 ± 0.79 m w.e., respectively. The mass loss on Yala Glacier from 2000 to 2012 is −8.92 ± 6.33 m w.e. The winter balance of Yala Glacier is positive, and the summer balance is negative in every investigated year. The summer balance determines the annual balance. Compared to regional mean geodetic mass-balance rates in the Nepalese Himalaya, the mean mass-balance rate of Rikha Samba Glacier is in a similar range, and the mean mass-balance rate of Yala Glacier is more negative because of the small and low-lying accumulation area. During the study period, a change of Yala Glacier's surface topography has been observed with glacier thinning and downwasting. The retreat rates of Rikha Samba Glacier are higher than for Yala Glacier. From 1989 to 2013, Rikha Samba Glacier retreated 431 m (−18.0 m a−1), and from 1974 to 2016 Yala Glacier retreated 346 m (−8.2 m a−1). The data of the annual and seasonal mass balances, point mass balance, geodetic mass balance, and length changes are accessible from the World Glacier Monitoring Service (WGMS, 2021), https://doi.org/10.5904/wgms-fog-2021-05.

Increasing the amount of soil organic carbon (SOC) has agronomic benefits and the potential to mitigate climate change. Previous regional predictions of SOC trends under climate change often ignore or do not explicitly consider the effect of crop adaptation (i.e., changing planting dates and varieties). We used the DayCent biogeochemical model to examine the effect of adaptation on SOC for corn and soybean production in the U.S. Corn Belt using climate data from three models. Without adaptation, yields of both corn and soybean tended to decrease and the decomposition of SOC tended to increase leading to a loss of SOC with climate change compared to a baseline scenario with no climate change. With adaptation, the model predicted a substantially higher crop yield. The increase in yields and associated carbon input to the SOC pool counteracted the increased decomposition in the adaptation scenarios, leading to similar SOC stocks under different climate change scenarios. Consequently, we found that crop management adaptation to changing climatic conditions strengthen agroecosystem resistance to SOC loss. However, there are differences spatially in SOC trends. The northern part of the region is likely to gain SOC while the southern part of the region is predicted to lose SOC.

Natural climate solutions provide opportunities to reduce greenhouse gas emissions and the United States is among a growing number of countries promoting storage of carbon in agricultural soils as part of the climate solution. Historical patterns of soil organic carbon (SOC) stock changes provide context about mitigation potential. Therefore, our objective was to quantify the influence of climate-smart soil practices on SOC stock changes in the top 30 cm of mineral soils for croplands in the United States using the DayCent Ecosystem Model. We estimated that SOC stocks increased annually in US croplands from 1995 to 2015, with the largest increase in 1996 of 16.6 Mt C (95% confidence interval ranging from 6.1 to 28.2 Mt CO 2  eq.) and the lowest increase in 2015 of 10.6 Mt C (95% confidence interval ranging from − 1.8 to 22.2 Mt C). Most climate-smart soil practices contributed to increases in SOC stocks except for winter cover crops, which had a negligible impact due to a relatively small area with cover crop adoption. Our study suggests that there is potential for enhancing C sinks in cropland soils of the United States although some of the potential has been realized due to past adoption of climate-smart soil practices.

Nitrogen (N) loss through ammonia ( NH 3 ) volatilization in agricultural soils is a significant source of atmospheric NH 3 , contributing to low N use efficiency in crops, risk to human health, environmental pollution, and is an indirect source of nitrous oxide ( N 2 O ) emissions. Our objective was to develop an ammonia volatilization method within the DayCent ecosystem model that incorporates key 4R N management practices (right type, right rate, right placement, and right timing) that influence NH 3 volatilization associated with application of urea-based nitrogen fertilizers to agricultural soils. The NH 3 volatilization method was developed with Bayesian calibration using sampling importance resampling methods and Bayes factors to select the level of complexity in the model that best represents NH 3 volatilization given the observed data. The final model included urea hydrolysis and the influence of urease inhibitors; short-term soil pH changes following fertilization; fertilizer incorporation into the soil (mechanically and through irrigation/precipitation); and specification of the fertilizer placement method (i.e. broadcast vs. banding and surface vs incorporated). DayCent predicts NH 3 volatilization with a root-mean-squared error of 158 (95% interval ranging from 133 to 192), bias of 7 (95% interval ranging from − 106 to 102) g NH 3 -N ha −1  day −1 , and with a Bayesian R 2 value of 0.39 (95% interval ranging from 0.17 to 0.62). Furthermore, the model incorporates key management options influencing NH 3 volatilization related to placement method and fertilizer type with and without urease inhibitors that can be used to evaluate management and policy options for reducing losses of NH 3 from urea fertilization.

Despite their importance for regional water resource planning and as indicators of climate change, records of in situ glacier mass balance remain short and spatially sparse in the Himalaya. Here, we present an updated series of in situ mass-balance measurements from Rikha Samba Glacier, Nepal, between 2011 and 2021. The updated in situ mass balance is −0.39 ± 0.32 m w.e. for this period. We use an energy-mass balance model to extend the annual mass-balance series back to 1974. The model is forced using daily meteorological variables from ERA5-Land reanalysis data that is linearly bias-corrected using observations from an automatic weather station situated near the glacier terminus. The modeled mass balance is consistent with the in situ mass-balance series measured 2011–2021 and with previous glaciological and geodetic estimates. The model results indicate a mass balance of −0.56 ± 0.27 m w.e. a−1 over the reconstruction period of 1974–2021, which is comparable to the mass losses experienced by other Himalayan glaciers during this time. An assessment of the sensitivity of the glacier mass balance to meteorological forcing suggests that a change in temperature of ±1 K has a stronger effect on the calculated mass balance compared to a ±20% change in either precipitation, or relative humidity, or solar radiation.

Key Clinical Message This case report emphasizes the crucial need to include vitamin B12 deficiency in the differential diagnosis of hemolytic anemia, despite its rarity as a presentation. The case illustrates that non‐immune hemolytic anemia can occur secondary to severe vitamin B12 deficiency, which can be effectively treated with vitamin B12 supplementation. Early recognition and comprehensive evaluation are essential for identifying this uncommon yet significant cause of hemolysis, ensuring prompt and appropriate treatment to improve patient outcomes.

Background: Atrial fibrillation (AF) is a common morbid arrhythmia that can cause thromboembolic events such as stroke. Despite advancements in diagnostic technologies, a significant number of AF patients may remain undetected and undiagnosed, and these asymptomatic patients possess sufficient risk of cardioembolic stroke. Identifying such patients through appropriate screening techniques and timely initiation of systemic anticoagulation therapy is essential to prevent such life‐threatening complications. Objectives: The objectives of this study encompass screening of AF among residents of the Dhulikhel Municipality and identifying its prevalence, along with evaluation of stroke risk and use of antithrombotic therapy in patients confirmed with AF. Methods: All residents of four wards of Dhulikhel Municipality, aged 50 years and above ( n  = 2048), underwent one‐time electrocardiogram (ECG) screening using a portable 12‐lead ECG machine. The cardiologist checked the cardiogram, and suspected AF cases were referred to the hospital for further evaluation and appropriate management. They were followed up to find out information on disease confirmation and management. Results: Out of 2048 participants, AF was detected in 16 participants, resulting in an overall prevalence of 0.78% (CI 0.4%–1.3%). The prevalence of AF was highest (2.98%) in population aged 80 years and above. Among individuals with AF, the median age was 71.5 (66.3–79.5) years, 50.0% were male and 75.0% had high stroke risk as indicated by a CHA 2 DS 2 ‐VASc score ≥ 2. Among these patients, only 41.66% were treated with oral anticoagulants (OACs), while 58.34% were treated either with single or dual antiplatelet therapy (DAPT). Conclusion: This study provided important insight into the prevalence of AF at the community level. Many AF patients were at high risk of stroke, but the OAC use was less than 50%. Screening of AF needs to be carried out on a larger scale in Nepal for early detection and timely management of the disease.

Nitrous oxide (N₂O) is an important greenhouse gas (GHG) that also contributes to depletion of ozone in the stratosphere. Agricultural soils account for about 60% of anthropogenic N₂O emissions. Most national GHG reporting to the United Nations Framework Convention on Climate Change assumes nitrogen (N) additions drive emissions during the growing season, but soil freezing and thawing during spring is also an important driver in cold climates. We show that both atmospheric inversions and newly implemented bottom-up modeling approaches exhibit large N₂O pulses in the northcentral region of the United States during early spring and this increases annual N₂O emissions from croplands and grasslands reported in the national GHG inventory by 6 to 16%. Considering this, emission accounting in cold climate regions is very likely underestimated in most national reporting frameworks. Current commitments related to the Paris Agreement and COP26 emphasize reductions of carbon compounds. Assuming these targets are met, the importance of accurately accounting and mitigating N₂O increases once CO₂ and CH₄ are phased out. Hence, the N₂O emission underestimate introduces additional risks into meeting long-term climate goals.

Nitrous oxide (ᴺ²ᴼ) is an important greenhouse gas (GHG) that also contributes to depletion of ozone in the stratosphere. Agricultural soils account for about 60% of anthropogenic ᴺ²ᴼ emissions. Most national GHG reporting to the United Nations Framework Convention on Climate Change assumes nitrogen (N) additions drive emissions during the growing season, but soil freezing and thawing during spring is also an important driver in cold climates. We show that both atmospheric inversions and newly implemented bottom-up modeling approaches exhibit large ᴺ²ᴼ pulses in the northcentral region of the United States during early spring and this increases annual ᴺ²ᴼ emissions from croplands and grasslands reported in the national GHG inventory by 6 to 16%. Considering this, emission accounting in cold climate regions is very likely underestimated in most national reporting frameworks. Current commitments related to the Paris Agreement and COP26 emphasize reductions of carbon compounds. Assuming these targets are met, the importance of accurately accounting and mitigating ᴺ²ᴼ increases once ᶜᴼ² and CH4 are phased out. Hence, the ᴺ²ᴼ emission underestimate introduces additional risks into meeting long-term climate goals.