Data collection
The first step in this study was to obtain all the data required. This primarily included data covering the factors for tick habitat suitability. All data is listed in Table 1. The specific climate variables used in the analysis are listed in Table 2.
Name | Source | Time period | Original format |
Tick distribution data | Global Biodiversity Information Facility (GBIF) records | 1900-2022 | Point data |
Deer distribution data | GBIF records | 1665-2022 | Point data |
Climate data | ClimateNA | Historical annual normals: 1991 to 2020
Future annual normals: 2041- 2070 |
Raster data
4x4km spatial resolution |
Map of Canada/ON and Quebec Boundaries | Statistics Canada | 2016 | Polygon data |
Land use cover data | Natural resources Canada
|
2019 | Raster data, 30m spatial resolution |
Soil Data | Agriculture and Agri-Food Canada
|
2015 | Polygon data |
Ontario parks | Government of Ontario
|
2020 | Polygon data |
Quebec Parks | Données Québec
|
2019 | Polygon data |
Nova Scotia Parks | Open Data Nova Scotia
|
2022 | Polygon data |
New Brunswick Parks | Open Data NB
|
2020 | Polygon data |
Table 1: Data
**A Digital Elevation Model (DEM) was not used in this analysis as elevation is not noted to be a strong impacting factor on tick presence.
Climate Variables
Annual Variables | |
Abbreviation | Name |
MAT | Mean Annual Temperature (°C) |
MWMT | mean warmest month temperature (°C), |
MCMT | mean coldest month temperature (°C), |
TD | temperature difference between MWMT and MCMT, or continentality (°C), |
MAP | mean annual precipitation (mm), |
MSP | May to September precipitation (mm), |
AHM | annual heat-moisture index (MAT+10)/(MAP/1000)) |
SHM | summer heat-moisture index ((MWMT)/(MSP/1000)) |
Derived Annual Variables | |
DD<0 | degree-days below 0°C, chilling degree-days |
DD>5 | degree-days above 5°C, growing degree-days |
DD<18 | degree-days below 18°C, heating degree-days |
DD>18 | degree-days above 18°C, cooling degree-days |
NFFD | the number of frost-free days |
FFP | frost-free period |
bFFP | the day of the year on which FFP begins |
eFFP | the day of the year on which FFP ends |
PAS | precipitation as snow (mm) between August in previous year and July in current year |
EMT | extreme minimum temperature over 30 years |
EXT | extreme maximum temperature over 30 years |
Eref | Hargreaves reference evaporation (mm) |
CMD | Hargreaves climatic moisture deficit (mm)
(sum of the monthly difference between a reference evaporation (Eref) and precipitation) – provides an estimate of monthly water balance by considering Hargreaves reference evapotranspiration and precipitation (Griesbauer et al., 2021) |
MAR | mean annual solar radiation (MJ m^2 d^1) |
RH | mean annual relative humidity (%) |
CMI | Hogg’s climate moisture index (mm) |
DD1040 | (10<DD<40) degree-days above 10°C and below 40°C |
Table 2: Climate variables
Explanations of climate variables from: https://www.climatewna.com/help/climateBC/help.htm