2024_VIIRS_CumTemp_IxodesRicinus

Abstract:

This dataset presents cumulative temperature masks that identify areas that are warm enough to stimulate tick questing activity, using a temperature threshold of 6 C. A series of scripts download and process VIIRS EO imagery of Land Surface Temperature to create temperature masks every 8 days using a combination of decadal (8-day) and daily satellite data. This dataset is an updated version for 2024.

These result in Boolean masks where suitable areas according to temperature limits on I. ricinus are identified as 1 and unsuitable areas as 0.  This mask can then be applied to the existing seasonal Tick model to make a more timely prediction of tick activity based on recent temperatures.

This dataset will be updated every couple of months by the end of the year 2024.  The current update is till mid October 2024. The last update will be in January 2025. 

Image acquisition:

Two different products are downloaded VIIRS Land Surface Temperature/Emissivity 8-day L3 Global 1 km SIN grid (VNP21A2, version 6) and VIIRS Land Surface Temperature/Emissivity Daily L3 Global 1 km SIN grid (VNP21A1D, version 6). 

Processing:
The cumulative temperature mask is processed in two steps through two separate scripts:

a. Acquisition of 1km VIIRS Land Surface Temperature imagery from NASA's data repository.
b. Importing of the imagery into a suitable format from which regularly updated masks are calculated.

File naming schema:

 ER+ year  + 8-day number (46 in total) for example:  ER2433C68.tif   24 refers to the year 2024 and 33 (decadal number) in this example refers to the 22nd of September.

ERCumTemp + year + month+ day: ERCumTemp240109.jpg,  240109  refers to the 8-day starting 9th of January.

gif file presents time-series animation for a whole year. 

Projection + EPSG code:
Latitude-Longitude/WGS84 (EPSG: 4326)
Spatial extent:
Extent  -32.0000000000000000,10.0000000000000000 : 68.9999999999999574,81.9999999999999716
Spatial resolution:
0.0083333 deg (approx. 1000 m)  
Temporal resolution:
8-day for year 2024

Pixel values:

Suitable areas as 1 and unsuitable areas as 0

Source: 
 VIIRS NASA :VNP21A2 and VNP21A1D

Software used:
Codes for modelling are in Python 
The software used for map production is ESRI ArcMap 10.8

License: CC-BY-SA 4.0
Processed by:
ERGO (Environmental Research Group Oxford) https://ergoonline.co.uk/ for the H2020 MOOD project