Update README.md

README.md

@@ -152,7 +152,7 @@ The Canopy-App input data in [Table 2](#table-2-canopy-app-required-input-variab
 | **External Canopy Variables**    | **Variable Description and Units**          | **Data Source/Reference (if necessary)**           |
 | `fh`                             | Forest canopy height (m)                    | Fused GEDI/Landsat data. Data Period=2020. Data frequency=Annual. ([Potapov et al., 2020](https://doi.org/10.1016/j.rse.2020.112165)) |
 | `clu`                            | Forest clumping index (dimensionless)       | GriddingMachine/MODIS. Data Period=2001-2017 Climatology. Data frequency=Monthly. ([Wei et al., 2019](https://doi.org/10.1016/j.rse.2019.111296)). Extended globally for high latitudes using methods described [here](https://gmuedu-my.sharepoint.com/:w:/g/personal/whung_gmu_edu/EdglXmW2kzBDtDj1xV0alGcB1Yo2I8hzdyWGVGB2YOTfgw). |
-| `lai`                            | Leaf area index (m2/m2)                     | VIIRS-NPP. Data Period=2020. Data frquency=Daily, interpolated from original 8-day product. ([Myneni 2018](https://doi.org/10.5067/VIIRS/VNP15A2H.001)). Extended globally for high latitudes using methods described [here](https://gmuedu-my.sharepoint.com/:w:/g/personal/whung_gmu_edu/EdglXmW2kzBDtDj1xV0alGcB1Yo2I8hzdyWGVGB2YOTfgw). |
+| `lai`                            | Leaf area index (m2/m2)                     | VIIRS-NPP. Data Period=2020. Data frequency=Daily, interpolated from original 8-day product. ([Myneni 2018](https://doi.org/10.5067/VIIRS/VNP15A2H.001)). Extended globally for high latitudes using methods described [here](https://gmuedu-my.sharepoint.com/:w:/g/personal/whung_gmu_edu/EdglXmW2kzBDtDj1xV0alGcB1Yo2I8hzdyWGVGB2YOTfgw). |
 | `ffrac`                          | Forest fraction (dimensionless)             | Based on [VIIRS GVF-NPP](https://www.star.nesdis.noaa.gov/jpss/gvf.php) and GriddingMachine/MODIS FFRAC/FVC from Terra.  Data Period=2020. Data frequency=Annual. ([DiMiceli et al., 2022](https://doi.org/10.5067/MODIS/MOD44B.061)). Extended globally for high latitudes using methods described [here](https://gmuedu-my.sharepoint.com/:w:/g/personal/whung_gmu_edu/EdglXmW2kzBDtDj1xV0alGcB1Yo2I8hzdyWGVGB2YOTfgw). |
 | `pavd`                           | Plant area volume density (m2/m3)           | [GEDI product from North Arizona University](https://goetzlab.rc.nau.edu/index.php/gedi/). Data Period=201904-202212 Climatology. Data frequency=Annual. Three dimensional structure of plant area volume density with 14 vertical layers from the surface (0 m) to 70 m above ground level. Data at each layer represents the average pavd within certain height range (e.g. 0 - 5 m for first layer). |
 | **Other External Variables**     | **Variable Description and Units**          | **Data Source/Reference (if necessary)**           |