Vegetation Indices

This API endpoint provides vegetation index metrics extracted for Brazilian municipalities from satellite imagery acquired by the MODIS (Moderate Resolution Imaging Spectroradiometer) sensor onboard the Terra satellite.

The metrics are obtained from the MOD13Q1 v6.1 product, available through the WTSS (Web Time Series Service) maintained by the Brazilian National Institute for Space Research (INPE).

The MOD13Q1 product provides the NDVI and EVI vegetation indices directly, as well as spectral reflectance bands used to derive additional indicators such as SAVI and NDWI.

Each observation in the original product corresponds to a 16-day composite, generated using a best-pixel compositing algorithm that prioritizes observations with:

• lower cloud coverage;
• lower viewing angle;
• higher spectral quality.

Before being made available through this endpoint, the original observations are spatially aggregated to Brazilian municipalities using the official IBGE municipal boundaries while preserving the original temporal resolution of the product.

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Source Product

Characteristic	Value
Source	INPE / WTSS
Product	MOD13Q1 v6.1
Sensor	MODIS (Terra)
Spatial resolution	250 meters
Temporal resolution	16 days
Geographic coverage	Brazil
Data type	Raster

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Data Processing

Before publication through the API, the data undergo the following processing steps.

Spatial aggregation

For each Brazilian municipality:

1. the municipal geometry is obtained from IBGE;
2. the geometry is converted to WGS84 (EPSG:4326);
3. a spatial query is performed against the WTSS service;
4. summary statistics are computed considering all pixels within the municipality.

Duplicate removal

Duplicate records are removed considering:

• observation date;
• attribute;
• collection.

Only the first valid occurrence is retained.

Derived indices

In addition to the indices directly provided by MOD13Q1, the following derived indices are calculated:

• SAVI (Soil Adjusted Vegetation Index)
• NDWI (Normalized Difference Water Index)

These indices are computed from the spectral reflectance bands provided by the original product.

Numerical safeguards

To prevent division-by-zero during the computation of derived indices, a minimum value of

1e-6

is applied to the following reflectance bands:

• NIR Reflectance;
• Red Reflectance;
• MIR Reflectance.

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Available Metrics

Each observation contains spatial summary statistics computed over the municipality.

Available statistics include:

• mean (mean)
• standard deviation (std)
• median (median)
• first quartile (q25)
• third quartile (q75)
• minimum (min)
• maximum (max)

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Available Indices

NDVI

Index used to estimate vegetation vigor and density.

$$NDVI = \frac{NIR - RED}{NIR + RED}$$

EVI

Vegetation index designed to reduce atmospheric effects and minimize saturation in densely vegetated areas.

$$EVI = 2.5 \times \frac{NIR - RED}{NIR + 6 \times RED - 7.5 \times BLUE + 1}$$

SAVI

Vegetation index designed to reduce the influence of exposed soil.

$$SAVI = 1.5 \times \frac{NIR - RED}{NIR + RED + 0.5}$$

NDWI

Index used to estimate vegetation and surface water content.

$$NDWI = \frac{NIR - MIR}{NIR + MIR}$$

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Endpoint

GET /api/datastore/vegetation/

---

Input Parameters

Parameter	Required	Type	Description
page	Yes	int	Page number
per_page	Yes	int	Number of items per page (maximum 100)
start	Yes	string (YYYY-mm-dd)	Start date
end	Yes	string (YYYY-mm-dd)	End date
geocode	No	int	IBGE municipality code
uf	No	string	Two-letter Brazilian state abbreviation
collection	No	string	Satellite data collection
attribute	No	string	Vegetation index or spectral band

---

Response Structure

Items

Field	Type	Description
date	date	Observation date
geocode	int	IBGE municipality code
collection	string	Source collection
attribute	string	Vegetation index or spectral band
mean	float	Mean value across the municipality
std	float	Standard deviation
median	float	Median
q25	float	First quartile
q75	float	Third quartile
min	float	Minimum value
max	float	Maximum value

All numeric values are rounded to four decimal places.

---

Pagination

Pagination information is included in the response.

"pagination": {
    "items": 10,
    "total_items": 10,
    "page": 1,
    "total_pages": 1,
    "per_page": 100
}

---

Examples

Python

import mosqlient

mosqlient.get_vegetation(
    api_key=api_key,
    start_date="2024-01-01",
    end_date="2024-02-01",
    geocode=3304557,
)

R

library(httr)
library(jsonlite)

veg_api <- "https://api.mosqlimate.org/api/datastore/vegetation/"
page <- "1"

pagination <- paste0("?page=", page, "&per_page=100&")
filters <- paste0("start=2024-01-01&end=2024-02-01")

headers <- add_headers(
    `X-UID-Key` = API_KEY
)

url <- paste0(veg_api, pagination, filters)

resp <- GET(url, headers)

content <- content(resp, "text")

json_content <- fromJSON(content)

items <- json_content$items
pagination_data <- json_content$pagination

curl

curl -X GET \
'https://api.mosqlimate.org/api/datastore/vegetation/?start=2024-01-01&end=2024-02-01&page=1&per_page=100' \
-H 'accept: application/json' \
-H 'X-UID-Key: YOUR_API_KEY'

Querying a specific municipality:

curl -X GET \
'https://api.mosqlimate.org/api/datastore/vegetation/?start=2024-01-01&end=2024-02-01&geocode=3304557&page=1&per_page=100' \
-H 'accept: application/json' \
-H 'X-UID-Key: YOUR_API_KEY'

---

Notes

• The data originate from the MOD13Q1 v6.1 product derived from the MODIS/Terra sensor.
• The original spatial resolution is 250 meters.
• The original temporal resolution is 16 days.
• Statistics are computed over the entire area of each Brazilian municipality.
• Municipal boundaries are based on the official IBGE municipal boundary dataset.
• NDVI and EVI are directly provided by the MOD13Q1 product.
• SAVI and NDWI are derived during preprocessing from the spectral reflectance bands.
• All metrics are spatially aggregated before being published through the API.