Pollen Index
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What is the Universal Pollen Index (UPI)?
The Universal Pollen Index (UPI) is designed to offer a globally unified scale
for comparing pollen levels across different areas. The index helps assess the
risk of pollen exposure based on various factors for people allergic or
sensitive to pollen. Based on a multilayer model, it is a representation of
pollen level data that considers the concentration per plant model, many
different local pollen indices (LPI) used worldwide, and the allergenicity of
different plant pollen types to predict the number of pollen grains per cubic
meter (grains/m3) per day.
The heatmapTiles endpoint returns heatmap tiles that can be overlaid
on a basemap. Heatmap tiles display the UPI across the globe for a given plant
type (TREE, GRASS, or WEED).
The index consists of six categories:
| Value |
Color |
Description |
| 0 |
 |
None |
| 1 |
|
Very Low |
| 2 |
|
Low |
| 3 |
|
Moderate |
| 4 |
|
High |
| 5 |
|
Very High |
Each category is based on specific concentration levels of pollen in a
particular area and their effect on the severity of allergic symptoms that are
usually experienced, providing a comprehensive representation of pollen levels.
By integrating the UPI, users can compare and assess pollen conditions in
various locations.
For example, the following heatmap tile shows TREE pollen levels ranging from
Very Low to Very High:
Supported plants
The Pollen API supports 3 different types of plants: Grass, Weed,
and Tree. Because a plant's availability is subject to actual data source
measurements and reports, Pollen API plant data may vary across locations.
The following list shows supported plant codes and their metadata:
| Plant Code |
Display Name |
Type |
ALDER |
Alder |
Tree |
ASH |
Ash |
Tree |
BIRCH |
Birch |
Tree |
COTTONWOOD |
Cottonwood |
Tree |
ELM |
Elm |
Tree |
MAPLE |
Maple |
Tree |
OLIVE |
Olive |
Tree |
JUNIPER |
Juniper |
Tree |
OAK |
Oak |
Tree |
PINE |
Pine |
Tree |
CYPRESS_PINE |
Cypress pine |
Tree |
HAZEL |
Hazel |
Tree |
GRAMINALES |
Grasses |
Grass |
JAPANESE_CEDAR |
Japanese cedar |
Tree |
JAPANESE_CYPRESS |
Japanese cypress |
Tree |
RAGWEED |
Ragweed |
Weed |
MUGWORT |
Mugwort |
Weed |
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Last updated 2025-08-27 UTC.
[null,null,["Last updated 2025-08-27 UTC."],[[["\u003cp\u003eThe Universal Pollen Index (UPI) provides a globally unified scale for comparing pollen levels, aiding in assessing pollen exposure risk.\u003c/p\u003e\n"],["\u003cp\u003eThe UPI utilizes a six-category system (None, Very Low, Low, Moderate, High, Very High) to represent pollen concentration and potential allergy symptom severity.\u003c/p\u003e\n"],["\u003cp\u003eHeatmap tiles visually display the UPI globally for three plant types: Tree, Grass, and Weed, allowing for easy comparison across locations.\u003c/p\u003e\n"],["\u003cp\u003eSupported plant types in the Pollen API include a variety of trees, grasses, and weeds, although availability may vary based on data source and location.\u003c/p\u003e\n"]]],["The Universal Pollen Index (UPI) is a global scale for comparing pollen levels, assessing pollen exposure risk. It utilizes a multilayer model, considering concentration per plant, local pollen indices, and allergenicity to predict pollen grains per cubic meter. The UPI ranges from 0 (None) to 5 (Very High), using heatmap tiles to visualize `TREE`, `GRASS`, or `WEED` pollen. The API supports various plant types, including `ALDER`, `OAK`, `GRAMINALES`, `RAGWEED`, and more.\n"],null,["# Pollen Index\n\nWhat is the Universal Pollen Index (UPI)?\n-----------------------------------------\n\nThe Universal Pollen Index (UPI) is designed to offer a globally unified scale\nfor comparing pollen levels across different areas. The index helps assess the\nrisk of pollen exposure based on various factors for people allergic or\nsensitive to pollen. Based on a multilayer model, it is a representation of\npollen level data that considers the concentration per plant model, many\ndifferent local pollen indices (LPI) used worldwide, and the allergenicity of\ndifferent plant pollen types to predict the number of pollen grains per cubic\nmeter (grains/m3) per day.\n\nThe heatmapTiles endpoint returns heatmap tiles that can be overlaid\non a basemap. Heatmap tiles display the UPI across the globe for a given plant\ntype (`TREE`, `GRASS`, or `WEED`).\n\nThe index consists of six categories:\n\n| Value | Color | Description |\n|-------|-------|-------------|\n| 0 | | None |\n| 1 | | Very Low |\n| 2 | | Low |\n| 3 | | Moderate |\n| 4 | | High |\n| 5 | | Very High |\n\nEach category is based on specific concentration levels of pollen in a\nparticular area and their effect on the severity of allergic symptoms that are\nusually experienced, providing a comprehensive representation of pollen levels.\nBy integrating the UPI, users can compare and assess pollen conditions in\nvarious locations.\n\nFor example, the following heatmap tile shows `TREE` pollen levels ranging from\n**Very Low** to **Very High**:\n\nSupported plants\n----------------\n\nThe Pollen API supports 3 different types of plants: **Grass** , **Weed** ,\nand **Tree**. Because a plant's availability is subject to actual data source\nmeasurements and reports, Pollen API plant data may vary across locations.\n\nThe following list shows supported plant codes and their metadata:\n\n| Plant Code | Display Name | Type |\n| `ALDER` | Alder | Tree |\n| `ASH` | Ash | Tree |\n| `BIRCH` | Birch | Tree |\n| `COTTONWOOD` | Cottonwood | Tree |\n| `ELM` | Elm | Tree |\n| `MAPLE` | Maple | Tree |\n| `OLIVE` | Olive | Tree |\n| `JUNIPER` | Juniper | Tree |\n| `OAK` | Oak | Tree |\n| `PINE` | Pine | Tree |\n| `CYPRESS_PINE` | Cypress pine | Tree |\n| `HAZEL` | Hazel | Tree |\n| `GRAMINALES` | Grasses | Grass |\n| `JAPANESE_CEDAR` | Japanese cedar | Tree |\n| `JAPANESE_CYPRESS` | Japanese cypress | Tree |\n| `RAGWEED` | Ragweed | Weed |\n| `MUGWORT` | Mugwort | Weed |\n|--------------------|------------------|-------|"]]
