We are provoding a set of table and maps that provides summary of ecosystem carbon balance (pools and fluxes) as simulated by the Dynamic Organic Soil version of the Terrestrial Ecosystem Model. Simulations are provided for the historical period from 1950 to 2009 and projections from 2010 to 2099, for the four main landscape conservation cooperative regions in Alaska (i.e. the Arctic, the Western Alaska, the North Pacific and the Northwest Boreal LCCs). Projections have been conducted at 1km-resolution for two set of climate scenarios for the A1B, B1 and A2 emission scenarios of the Intergovernmental Panel on Climate Change Special Report on Emissions Scenarios (IPCC-SRES). The two global circulation models used for these projections are (1) the 5th generation of the ECHAM general circulation model from the Max Planck Institute for Meteorology (ECHAM5), and (2) the fourth generation global circulation model from the Canadian Centre for Climate Modelling and Analysis (CCCMA). Pools and fluxes are summarized for uplands and lowlands separately. Vegetation carbon pools only concern living biomass. Soil carbon pools include organic layers, 1m deep mineral layers and dead woody debris. Positive fluxes indicate carbon assimilated to the ecosystem. Negative fluxes indicate carbon released to the atmosphere. Carbon fluxes are vegetation Net Primary Productivity (NPP), soil Heterotrophic respiration (HR), CO & CO2 and CH4 fire emissions from organic layer and vegetation burning (PYRO_COCO2 and PYRO_CH4 respectively), biogenic CH4 fluxes (BIO_CH4) and Net Ecosystem Carbon Balance (NECB).

To meet the climate change planning and adaptation needs of Alaska managers and decision makers, I developed a set of statewide summaries of available climate change projections that can be further subset using GIS techniques for requests by management unit, watershed, or other location. This facilitates the development of tailored climate futures for decision makers’ regional or subregional management context. This file describes the source data and summaries for purposes of technical /scientific documentation. The methods and presentation for these datasets were adapted from products in previous USGS-approved IP products for the AKCASC Building Resilience Today project (e.g, Community of Kotlik et al. 2019). For each data product included, summaries (averages or totals) are presented for multiple climate models or specific global warming levels and are average dover two time periods: 2040-2069, or the “2050s”, for near-term decision framing; and 2070-2099, or the “2080s”, for longer-term decision framing. In all cases where possible, both moderate emissions (RCP4.5 or +2C global level) and higher emissions (RCP8.5, or +4C global level) are presented. These choices (model averaging, temporal averaging, and scenario presentation) are tailored to the main sources of uncertainty (Hawkins and Sutton 2009) in climate model projections, specifically differences in climate model construction, climatic variability, and emissions scenario uncertainty (e.g., Littell et al. 2011, Snover et al. 2013, Terando et al. 2020). Not all scenario planning or climate impacts modeling needs can be met with these projections – these are intended to characterize a range of futures indicated by the available data products and facilitate further exploration of climate impacts modeling and adaptation development options.

Boreal ecosystems comprise about one tenth of the world’s land surface and contain over 20 % of the global soil carbon (C) stocks. Boreal soils are unique in that the mineral soil is covered by what can be quite thick layers of organic soil. These organic soil layers, or horizons, can differ in their state of decomposition, source vegetation, and disturbance history. These differences result in varying soil properties (bulk density, C content, and nitrogen (N) content) among soil horizons. These data were used in a manuscript where these soil properties, as represented by over 3000 samples from Interior Alaska, were summarized. We also examined how soil drainage and stand age affect these attributes. The summary values presented in this manuscript can be used to gap-fill large datasets when important soil properties were not measured, provide data to initialize process-based models, and validate model results.

This data set provides estimates of 3-hourly net ecosystem CO2 exchange (NEE) at 0.5-degree resolution over the state of Alaska for 2012-2014. The NEE estimates are the output are from Geostatistical Inverse Modeling of a subset of CARVE aircraft CO2 data, WRF-STILT footprints, and PVPRM-SIF data from flux towers (CRV: located in Fox, AK and BRW: located just outside Barrow, AK). Daily mean NEE is also provided as calculated for all of Alaska and for four sub-regions (0.5-degree resolution) that were defined across Alaska, based on general landcover type: North Slope Tundra, South and West Tundra, Boreal Forests, and Mixed (all other). Also provided are derived annual carbon budgets for (1) all of Alaska with defined contributions from biogenic, fossil fuel, and biomass burning sources and (2) annual biogenic carbon budgets for the four landcover-type regions of Alaska. Provided for completeness are the CARVE aircraft atmospheric measurement data used in estimating NEE.

This dataset provides monthly estimates of biomass stocks and land-atmosphere carbon exchange across the western United States at 0.95 degrees longitude x 1.25 degrees latitude grid resolution from 1998 through 2010. The data include outputs from two types of model simulations: (1) a "free" simulation which used Community Land Model (CLM5.0) simulations forced with meteorology appropriate for complex mountainous terrain, and (2) "assimilation" runs using the land surface data assimilation system (CLM5-DART). In assimilation runs, the CLM5 vegetation state is constrained by remotely sensed observations of leaf area index and aboveground biomass, which influenced biomass stocks and carbon fluxes.

This simulated ecosystem carbon dataset is used to report terrestrial carbon budget of the conterminous U.S. in the Golobal Change Biology paper "Critical land change information enhances understanding of carbon balance in the U.S." The data is derived from simulations of the parallel Integrated Biosphere simulator (pIBIS). Annual carbon variables cover 1971-2015 at 1-km (960m) spatial resolution with 3052 rows and 4823 columns. Carbon stock and flux units are in kgC/m2 and kgC/m2/yr, respectively. Data are in NetCDF format and Albers equal area projection. Overall data creation steps: 1. The pIBIS model was used to run simulations using climate, vegetation, soil and disturbance input data; 2. Model outputs were converted to NetCDF format; 3. 1971-2015 subsets were clipped from original 1901-2015 simulation outputs. Variable List: aynbp – net biome productivity; ayneetot – net ecosystem productivity; aynpptot – net primary productivity; totceco – total ecosystem carbon. NoData Value: -3.40282346639e+038

Data from high frequency sampling of multiple carbon forms were collected in a predominately rain-fed watershed in Southeast Alaska during the main run-off season (May-October 2021). The dataset includes dissolved organic carbon, particulate organic carbon, coarse particulate organic carbon, and invertebrate biomass carbon point samples and daily stream flow. The objective of this study was to collect data on carbon export and flow to model watershed export of carbon forms.

Total and organic carbon values from soil samples taken from the Yukon River Basin, Alaska. These samples were used to create a relationship between total carbon and organic carbon for samples which were only run for total carbon.

Total and organic carbon values from soil samples taken from the Yukon River Basin, Alaska. These samples were used to create a relationship between total carbon and organic carbon for samples which were only run for total carbon.

Total and organic carbon values from soil samples taken from the Yukon River Basin, Alaska. These samples were used to create a relationship between total carbon and organic carbon for samples which were only run for total carbon.