scl3/task_hii_weightedsum repository overview

⁠HII WEIGHTED SUM TASK

This task adds the most recent Human Impact drivers for the specified date together, producing the final synthetic index dataset representing anthropogenic impact on the Earth's terrestrial surface: the Human Impact Index (HII). For more information, see [citation TBD].

⁠HII value ranges

Each of the drivers have a minimum value of 0 and a maximum value of 10 (though note the data is multiplied by 100 and stored as an integer to optimize precision and storage; actual values are thus 0-1000 for each driver). This task adds them together without weighting them (despite the task name), because the drivers themselves already have weights built in -- i.e. each driver's theoretical 0-10 range is absolute, not normalized, so that a value can be compared across drivers; thus the actual maximum weight from a driver (e.g. navigable water) can be less than 10.

Similarly, this task does not normalize. Therefore, the theoretical minimum and maximum values for HII on a given date are 0 and (10 * [number of drivers, currently 7]) respectively. In practice, however, because no single cell has a maximum value from all drivers, and because drivers are not normalized and so do not all have a maximum of 10, the actual maximum value will be more like 64.

⁠Drivers and output

The output HII from this task is stored in the Earth Engine ImageCollection at projects/HII/v1/hii. Like all Earth Engine images output from tasks based on task_base⁠, HII images are assigned a system:time_start based on the task's self.taskdate, which can be used for temporal selection and comparison.

⁠Drivers

⁠Variables and Defaults

⁠Environment variables

SERVICE_ACCOUNT_KEY=<GOOGLE SERVICE ACCOUNT KEY>

⁠Class constants

scale=300

⁠Usage

All parameters may be specified in the environment as well as the command line.

/app # python task.py --help
usage: task.py [-h] [-d TASKDATE] [--overwrite]

optional arguments:
  -h, --help            show this help message and exit
  -d TASKDATE, --taskdate TASKDATE
  --overwrite           overwrite existing outputs instead of incrementing

⁠License

Copyright (C) 2022 Wildlife Conservation Society The files in this repository are part of the task framework for calculating Human Impact Index and Species Conservation Landscapes (https://github.com/SpeciesConservationLandscapes⁠) and are released under the GPL license: https://www.gnu.org/licenses/#GPL⁠ See LICENSE⁠ for details.