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1. Agricultural production diversity and child nutrition in Ethiopia

   https://doi.org/10.1007/s12571-021-01173-9  

   Bakhtsiyarava, Maryia ; Grace, Kathryn ( April 2021 , Food Security)

   null (Ed.)

   Abstract This study investigates how two aspects of agricultural production diversity – farm production diversity and composition of production – relate to child height-for-age and weight-for-height in Ethiopia. We use longitudinal data on child anthropometric measurements, household farm production diversity and farm production composition from the Ethiopia Socioeconomic Survey for 2011, 2013, and 2015 available through the World Bank. Using longitudinal fixed effects models, we show that an increase in farm production diversity reduces the risk of chronic food insecurity (child height-for-age) but has no impact on acute measures of food insecurity (child weight-for-height). Results also suggest that, in a context of poor rainfall, more diversity in farm production can adversely impact child height-for-age, although livestock sales might mitigate that detrimental effect. These findings highlight the importance of considering the relationship between farm-level food production and child nutrition in a context of climate change. 

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2. CTEQ-TEA group updates: Photon PDF and Impact from heavy flavors in the CT18 global analysis

   https://doi.org/10.22323/1.398.0370  

   Guzzi, Marco ; Xie, Keping ; Hou, Tie-Jiun ; Nadolsky, Pavel ; Schmidt, Carl ; Yan, Mengshi ; Yuan, C.-P. ( March 2022 , CTEQ-TEA group updates: Photon PDF and Impact from heavy flavors in the CT18 global analysis)

   Sissa (Ed.)

   We discuss recent CTEQ-TEA group activities after the publication of the CT18 global analysis of parton distribution functions (PDFs) in the proton. In particular, we discuss a new calculation for the photon content in the proton, termed as CT18lux and CT18qed PDFs, and the impact of novel charm- and bottom-quark production cross section measurements at HERA on the CT18 global analysis. 

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3. As above, not so below: Long‐term dynamics of net primary production across a dryland transition zone

   https://doi.org/10.1111/gcb.16744  

   Brown, Renée F. ; Collins, Scott L. ( May 2023 , Global Change Biology)

   Drylands are key contributors to interannual variation in the terrestrial carbon sink, which has been attributed primarily to broad‐scale climatic anomalies that disproportionately affect net primary production (NPP) in these ecosystems. Current knowledge around the patterns and controls of NPP is based largely on measurements of aboveground net primary production (ANPP), particularly in the context of altered precipitation regimes. Limited evidence suggests belowground net primary production (BNPP), a major input to the terrestrial carbon pool, may respond differently than ANPP to precipitation, as well as other drivers of environmental change, such as nitrogen deposition and fire. Yet long‐term measurements of BNPP are rare, contributing to uncertainty in carbon cycle assessments. Here, we used 16 years of annual NPP measurements to investigate responses of ANPP and BNPP to several environmental change drivers across a grassland–shrubland transition zone in the northern Chihuahuan Desert. ANPP was positively correlated with annual precipitation across this landscape; however, this relationship was weaker within sites. BNPP, on the other hand, was weakly correlated with precipitation only in Chihuahuan Desert shrubland. Although NPP generally exhibited similar trends among sites, temporal correlations between ANPP and BNPP within sites were weak. We found chronic nitrogen enrichment stimulated ANPP, whereas a one‐time prescribed burn reduced ANPP for nearly a decade. Surprisingly, BNPP was largely unaffected by these factors. Together, our results suggest that BNPP is driven by a different set of controls than ANPP. Furthermore, our findings imply belowground production cannot be inferred from aboveground measurements in dryland ecosystems. Improving understanding around the patterns and controls of dryland NPP at interannual to decadal scales is fundamentally important because of their measurable impact on the global carbon cycle. This study underscores the need for more long‐term measurements of BNPP to improve assessments of the terrestrial carbon sink, particularly in the context of ongoing environmental change.

    

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4. New CTEQ global analysis with high precision data from the LHC

   https://doi.org/10.22323/1.352.0001  

   Yuan, C. P. ; Hou, Tie-Jiun ; Xie, Keping ; Jun, Gao ; Dulat, Sayipjamal ; Guzzi, Marco ; Hobbs, Timothy J. ; Huston, Joey Walter ; Nadolsky, Pavel ; Pumplin, Jon ; et al ( July 2019 , Proceedings of science)

   We present the new CTEQ-TEA global analysis of quantum chromodynamics (QCD). In this analysis, parton distribution functions (PDFs) of the nucleon are determined within the Hessian method at the next-to-next-to leading order (NNLO) in perturbative QCD, based on the most recent measurements from the Large Hadron Collider (LHC) and a variety of world collider data. Because of difficulties in fitting both the ATLAS 7 and 8 TeV W and Z vector boson production cross section data, we present two families of PDFs, named CT18 and CT18Z PDFs, respectively, without and with the ATLAS 7 TeV W and Z measurements. We study the impact of the CT18 family of PDFs on the theoretical predictions of standard candle cross sections at the LHC. 

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5. Surface Deformation and Seismicity Induced by Poroelastic Stress at the Raft River Geothermal Field, Idaho, USA

   https://doi.org/10.1029/2021GL095108  

   Li, Bing Q. ; Khoshmanesh, Mostafa ; Avouac, Jean‐Philippe ( September 2021 , Geophysical Research Letters)

   We investigate the relative importance of injection and production on the spatial‐temporal distribution of induced seismicity at the Raft River geothermal field. We use time‐series of InSAR measurements to document surface deformation and calibrate a hydro‐mechanical model to estimate effective stress changes imparted by injection and production. Seismicity, located predominantly in the basement, is induced primarily by poroelastic stresses from cold water reinjection into a shallower reservoir. The poroelastic effect of production from a deeper reservoir is minimal and inconsistent with observed seismicity, as is pore‐pressure‐diffusion in the basement and along reactivated faults. We estimate an initial strength excess of ∼20 kPa in the basement and sedimentary cover, but the seismicity rate in the sedimentary cover is four times lower, reflecting lower density of seed‐points for earthquake nucleation. Our modeling workflow could be used to assess the impact of fluid extraction or injection on seismicity and help design or guide operations.

    

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