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- Description:
- : Forests play a major role in the global carbon cycle. Previous studies on the capacity of forests to sequester atmospheric CO2 have mostly focused on carbon uptake, but the roles of carbon turnover time and its spatiotemporal changes remain poorly understood. Here, we used long-term inventory data (1955-2018) from 695 mature forest plots to quantify temporal trends in living vegetation carbon turnover time across tropical, temperate, and cold climate zones, and compared plot data to eight Earth system models (ESMs). Long-term plots consistently showed decreases in living vegetation carbon turnover time, likely driven by increased tree mortality across all major climate zones. Changes in living vegetation carbon turnover time were negatively correlated with CO2 enrichment in both forest plot data and ESM simulations. However, plot-based correlations between living vegetation carbon turnover time and climate drivers such as precipitation and temperature diverged from those of ESM simulations. Our analyses suggest that forest carbon sinks are likely to be constrained by a decrease in living vegetation carbon turnover time, and accurate projections of forest carbon sink dynamics will require an improved representation of tree mortality processes and their sensitivity to climate in ESMs.
- Subject:
- Forestry
- Creator:
- Anderegg, William R.L., Schraub, Marcus, Yu, Kailiang, Gessler, Arthur, Penuelas, Josep, Cailleret, Maxine, Peng, Changhui, Condit, Richard, Ferretti, Marco, Hubbell, Stephen P., Smith, William K., Sardans, Jordi, Levanic, Tom, Zhu, Kai, and Trugman, Anna T.
- Owner:
- KAILIANG YU
- Language:
- English
- Date Uploaded:
- 10/24/2019
- Date Modified:
- 12/09/2021
- Resource Type:
- Dataset
- Identifier:
- https://doi.org/doi:10.7278/S50D-D656-FSP2
-
- Description:
- We analyzed 4,754 broadband seismic recordings of the SKS, SKKS, and SPdKS wavefield from 13 high quality events sampling the Samoa ultralow-velocity zone (ULVZ). We measured differential travel-times and amplitudes between the SKKS and SKS arrivals, which are highly sensitive to the emergence of the SPdKS seismic phase, which is in turn highly sensitive to lowermost mantle velocity perturbations such as generated by ULVZs. We modeled these data using a 2-D axi-symmetric waveform modeling approach and are able to explain these data with a single ULVZ. In order to predict both travel-time and amplitude perturbations we found that a large ULVZ length in the great circle arc direction on the order of 10° or larger is required. The large ULVZ length limits acceptable ULVZ elastic parameters. Here we find that δVS and δVP reductions from 20% to 22% and 15% to 17% respectively gives us the best fit, with a thickness of 26 km. Initial 3-D modeling efforts do not recover the extremes in the differential measurements, demonstrating that 3-D effects are important and must be considered in the future. However, the 3-D modeling is generally consistent with the velocity reductions recovered with the 2-D modeling. These velocity reductions are compatible with a compositional component to the ULVZ. Furthermore, geodynamic predictions for a compositional ULVZ that is moving predict a long linear shape similar to the shape of the Samoa ULVZ we confirm in this study. and This collection includes radial component displacement seismograms in the time window including the SKS, SKKS and SPdKS seismic arrivals. These data all interact with the Samoa ultra-low velocity zone at the core-mantle boundary. All data used in the study of Krier et al., 2021 (JGR) is included in this collection.
- Subject:
- Geology, seismology, and Geophysics
- Creator:
- Michael S. Thorne, Tarje Nissen-Meyer, Justin D. Krier, and Kuangdai Leng
- Owner:
- Michael Thorne
- Based Near Label Tesim:
- Tonga Trench, , Tonga
- Language:
- English
- Date Uploaded:
- 02/17/2021
- Date Modified:
- 12/09/2021
- Date Created:
- January 2019 to January 2020
- Resource Type:
- Dataset
- Identifier:
- https://doi.org/10.7278/S50DT3X22GGB
-
- Description:
- Evaluator responses to compliance, understandability, actionability, and readability criteria, by base and type, for Hearing Conservation educational materials from active-duty, continental United States Air Force bases.
- Keyword:
- Flesch-Kincaid Grade Level (FKGL), Patient Education Materials Assessment Tool (PEMAT), Understandability, Military, Noise-Induced Hearing Loss (NIHL), Readability, Compliance, and Actionability
- Subject:
- Patient Education, Hearing Loss, Noise-Induced, Comprehension, and Compliance
- Creator:
- Garner, Clayton, Sleeth, Darrah, Handy, Rod, Dominguez, Thomas, and Pettit, Lucas
- Owner:
- Date Uploaded:
- 04/24/2024
- Date Modified:
- 04/24/2024
- Date Created:
- 2023-06-22 to 2023-08-01
- License:
- Public Domain – This data is free of copyright restrictions (e.g. government sponsored data).
- Identifier:
- https://doi.org/10.7278/S50d-9hy0-dbvp
-
- Description:
- Detailed ground-based observations of snow are scarce in remote regions such as the Arctic. Here, Multi-Angle Snowflake Camera (MASC) measurements of over 55,000 solid hydrometeors — obtained during a two-year period from August 2016 to August 2018 at Oliktok Point, Alaska — are analyzed and compared to similar measurements from an earlier experiment at Alta, Utah. In general, distributions of hydrometeor fall speed, fall orientation, aspect ratio, flatness, and complexity (i.e., riming degree) were observed to be very similar between the two locations, except that Arctic hydrometeors tended to be smaller. In total, the slope parameter defining a negative exponential of the size distribution was approximately 50% steeper in the Arctic as at Alta. 66% of particles were observed to be rimed or moderately rimed, with some suggestion that riming is favored by weak boundary layer stability. On average, the fall speed of rimed particles was not notably different from aggregates. However, graupel density and fall speed increase as cloud temperatures approach the melting point.
- Keyword:
- Oliktok Point, Alaska, hydrometeor fall orientation, Alta, fhydrometeor latness, snow, hydrometeor aspect ratio, hydrometeors, hydrometeor complexity, and hydrometeor fall speed
- Subject:
- Atmospheric Science
- Creator:
- Kyle E. Fitch and Timothy J. Garrett
- Owner:
- Based Near Label Tesim:
- Oliktok Point, Alaska, United States and Alta, Utah, United States
- Date Uploaded:
- 02/06/2022
- Date Modified:
- 12/06/2023
- Date Created:
- 2013-01-07 to 2013-04-22
- License:
- CC BY – Allows others to use and share your data, even commercially, with attribution.
- Resource Type:
- Dataset
- Identifier:
- https://doi.org/10.7278/S50d-0nmg-6bs4
-
- Description:
- Subglacial water pressures influence groundwater conditions in proximal alpine valley rock slopes, varying with glacier advance and retreat in parallel with changing ice thickness. Fluctuating groundwater pressures in turn increase or reduce effective joint normal stresses, affecting the yield strength of discontinuities. Here we extend simplified assumptions of glacial debuttressing to investigate how glacier loading cycles together with changing groundwater pressures generate rock slope damage and prepare future slope instabilities. Using hydromechanical coupled numerical models closely based on the Aletsch Glacier valley in Switzerland, we simulate Late Pleistocene and Holocene glacier loading cycles including long-term and annual groundwater fluctuations. Measurements of transient subglacial water pressures from ice boreholes in the Aletsch Glacier ablation area, as well as continuous monitoring of bedrock deformation from permanent GNSS stations helps verify our model assumptions. While purely mechanical glacier loading cycles create only limited rock slope damage in our models, introducing a fluctuating groundwater table generates substantial new fracturing. Superposed annual groundwater cycles increase predicted damage. The cumulative effects are capable of destabilizing the eastern valley flank of our model in toppling-mode failure, similar to field observations of active landslide geometry and kinematics. We find that hydromechanical fatigue is most effective acting in combination with long-term loading and unloading of the slope during glacial cycles. Our results demonstrate that hydromechanical stresses associated with glacial cycles are capable of generating substantial rock slope damage and represent a key preparatory factor for paraglacial slope instabilities.
- Subject:
- Geology
- Creator:
- Moore, Jeffrey, Loew, Simon, Limpach, Philippe, Gischig, Valentin, Grämiger, Lorenz, and Funk, Martin
- Owner:
- Jeff Moore
- Based Near Label Tesim:
- Aletsch Glacier, Valais, Switzerland
- Language:
- English
- Date Uploaded:
- 01/03/2020
- Date Modified:
- 12/09/2021
- Date Created:
- Borehole P1 20130712 09:28:09 to 20140808 09:11:14 and Borehole P2 20130716 05:00:03 to 20140808 22:10:44
- Resource Type:
- Dataset
- Identifier:
- https://doi.org/10.7278/S50D-A50H-3TE4
-
- Description:
- This dataset accounts for all jobs undertaken by the Société Le Roy Bouillon, a funerary monuments company in Paris, from 1890 to 1902. The first sheet, “Activity Data” accounts for each job and the fee charged to the client for that job. It also categories each job as either a new cemetery construction, maintenance to existing cemetery structures, or other jobs unrelated to cemetery construction. The second sheet, “Outside Paris,” summarizes the annual activity, recording the number of projects undertaken within Paris versus outside of the city, new constructions versus maintenance work, and revenue coming in from each type of job. The original records are currently housed in a private collection in Paris and were manually transcribed by the author.
- Keyword:
- Paris, France, funerary monuments, nineteenth centruy, cemeteries, and business history
- Subject:
- funerary structures, cemeteries, and nineteenth century (dates CE)
- Creator:
- Kaylee P. Alexander
- Owner:
- Kaylee Alexander
- Based Near Label Tesim:
- Paris, Île-de-France, France
- Language:
- English
- Date Uploaded:
- 02/09/2023
- Date Modified:
- 11/30/2023
- Date Created:
- 2020-01-01 to 2020-01-31
- License:
- CC BY NC - Allows others to use and share your data non-commercially and with attribution.
- Resource Type:
- Dataset
- Identifier:
- https://doi.org/10.7278/S50d-t4sn-67e3
-
- Description:
- The dataset was collected in the process of carrying out a research on the effects of photochemical aging and interactions with secondary organic aerosols on cellular toxicity of combustion particles between the year 2021 to 2022
- Keyword:
- combustion particles, photochemical aging, and secondary organic aerosols
- Subject:
- combustion, combustion products, photochemical reactions, and aerosols
- Creator:
- Attah Reuben, Kerry Kelly, and Kamaljeet Kaur
- Owner:
- Reuben Attah
- Based Near Label Tesim:
- University of Utah, Utah, United States
- Language:
- English
- Date Uploaded:
- 02/09/2023
- Date Modified:
- 11/30/2023
- Date Created:
- 2021-06-01 to 2022-12-31
- License:
- CC BY – Allows others to use and share your data, even commercially, with attribution.
- Resource Type:
- Dataset
- Identifier:
- https://doi.org/10.7278/S50d-2a2h-jeaa
-
- Description:
- The data are bed-scale measurements taken from virtual outcrop models (Morris, E.A., Atlas, C.E., Johnson, C.L., 2023, Architectural analysis of the Panther Tongue - virtual outcrop models) and calibrated with measurements taken at outcrop in the field.
- Keyword:
- outcrop metrics, geology, delta lobes, virtual outcrop models, shallow marine sedimentology , reservoir characteristics, and geophysics
- Subject:
- Geography and Geophysics
- Creator:
- Atlas, Claire, Morris, Emma, and Johnson, Cari
- Contributor:
- Claire Atlas
- Owner:
- Emma Morris
- Based Near Label Tesim:
- Salt Lake City, Utah, United States
- Language:
- English
- Date Uploaded:
- 12/20/2022
- Date Modified:
- 12/04/2023
- Date Created:
- 2020-01-01 to 2022-05-31
- License:
- CC BY NC - Allows others to use and share your data non-commercially and with attribution.
- Resource Type:
- Dataset
- Identifier:
- https://doi.org/10.7278/S50d-40cy-rkf5
-
- Description:
- Ultralow-velocity zones (ULVZs) have been studied using a variety of seismic phases; however, their physical origin is still poorly understood. Short period ScP (S wave converted to, and reflected as, P wave from the core-mantle boundary) waveforms are extensively used to infer ULVZ properties because they may be sensitive to all ULVZ elastic moduli. However, ScP waveforms are additionally complicated by the effects of path attenuation, coherent noise, and source-time function (STF) complexity. To address these complications, we developed a hierarchical Bayesian inversion method that allows us to invert ScP waveforms from multiple events simultaneously and accounts for path attenuation and correlated noise. The inversion method is tested with synthetic predictions which show that the inclusion of attenuation is imperative to recover ULVZ parameters and that the ULVZ thickness and S-wave velocity decrease (δVS) are most reliably recovered. Utilizing multiple events reduces the effects of coherent noise and STF complexity, which in turns allows for the inclusion of more data to be used in the analyses. We next applied the method to ScP data recorded in Australia for 291 events that sample the CMB beneath the Coral Sea. Our results indicate that S-wave velocity across the region is ~-14% in average, but there is a greater variability in the south than that in the north. P-wave velocity reductions and density perturbations are mostly below 10%. These ScP data show more than one ScP post-cursor in some areas which may indicate complex 3-D ULVZ structures. Seismic data are provided for 291 earthquakes in Northern Territory, Australia.
- Keyword:
- seismology, mantel phases, ULVZ, and short period ScP waveforms
- Subject:
- Geology, Seismology, and Geophysics
- Creator:
- Pachhai, Surya and Thorne, Michael S.
- Owner:
- Surya Pachhai
- Based Near Label Tesim:
- Northern Territory, Northern Territory, Australia
- Language:
- English
- Date Uploaded:
- 12/10/2022
- Date Modified:
- 12/04/2023
- Date Created:
- 2005-01-01 to 2021-12-30.
- License:
- Public Domain – This data is free of copyright restrictions (e.g. government sponsored data).
- Resource Type:
- Dataset
- Identifier:
- https://doi.org/10.7278/S50d-a67s-y717
-
- Description:
- Abstract: Data for Performance evaluation of the Alphasense OPC-N3 and Plantower PMS5003 sensor in measuring dust events in the Salt Lake Valley, Utah This data file was used to estimate the performance of the Alphasense OPC-N3 and PMS5003 sensor in measuring ambient PM10, especially during dust events, and to obtain correction factors to correct the PMS5003 data. During April 2022, the OPC-N3 and PMS5003 sensors were collocated with federal equivalent method (FEM)at two Utah Division of Air Quality (UDAQ) sites: Hawthorne (HW) station and Environmental Quality (EQ) station. One residential site (RS)was also tested, with OPC-N3 and PMS5003 collocated with GRIMM portable aerosol spectrophotometer. The FEM data (PM2.5 and PM10 concentrations) and meteorological parameters (wind speed, wind direction, relative humidity, and temperature) for the two UDAQ sites were downloaded from the EPA website. The Excel sheet contained all the raw data and the processed data. The FEM, OPC-N3, and PMS5003 measurements were labeled as FEM-YYY, OPC-YYY, and PMS-YYY, where YYY represents the sites nomenclature, i.e., HW, EQ, and RS. The sheet labeled “HW”, “RS”, and,” EQ” contained the raw measurements (meteorological, PM10, and PM2.5 (whenever applicable)) for the sites. The sheet” PM-ratio-based correlation” provided the data used to get the PM-ratio-based correlation. Briefly, based on the ratio of FEM-HW PM2.5/PM10, the FEM-HW and PMS-HW PM10 measurements were segregated into six bins: PM2.5/PM10: <0.2, 0.2-0.3, 0.3-0.4, 0.4-0.5, 0.5-0.7, and >0.7. For each bin, the co-located PMS-HW PM10 concentrations were linearly regressed against the FEM-HW PM10 concentrations to obtain correction factors (slope and intercept). These correction factors were later used to correct the PMS PM10 concentrations at the other two locations (RS and EQ), presented in the sheets with labels “RS correction using GRIMM ratio”, “RS correction using opc ratio” and “EQ corrected using EQ ratio”. Each sheet also includes the calculation of RMSE and NRMSE of OPC-YYY and PMS-YYY against FEM-YYY, with YYY as the site nomenclature.
- Keyword:
- Plantower PMS5003, dust events, air pollution, air quality, ppticle particle counters, PM10, AQI, particulate matter, PM sensor, and Alphasense OPC-N3 performance during
- Subject:
- air pollution
- Creator:
- Kelly, Kerry and Kaur, Kamaljeet
- Owner:
- Based Near Label Tesim:
- Salt Lake City, Utah, United States
- Language:
- English
- Date Uploaded:
- 10/20/2022
- Date Modified:
- 12/04/2023
- Date Created:
- 2022-04-01 to 2022-04-30
- License:
- CC BY – Allows others to use and share your data, even commercially, with attribution.
- Resource Type:
- Dataset
- Identifier:
- https://doi.org/10.7278/S50d-xbns-3ge3