# Site Selection ### Overview Selecting an appropriate site is one of the most important factors in ensuring high-quality observations from a 3D-PAWS station. Even when sensors are functioning correctly, poor siting can result in measurements that are biased or not representative of local conditions. Site selection should prioritize **exposure, representativeness, and practical constraints**. *** ### Key Considerations When selecting a site, evaluate these factors: * **Exposure** – Are sensors unobstructed by buildings, trees, or terrain? * **Representativeness** – Does the site reflect the surrounding environment you want to measure? * **Solar Access** – Will the solar panel receive sufficient sunlight throughout the day? * **Communications** – Is cellular or WiFi connectivity available and reliable? * **Security** – Is the site protected from theft, vandalism, or accidental damage? * **Accessibility** – Can the station be safely installed and maintained over time? *** ### Instrument Siting Guidelines #### Rain Gauge * Place in an **open area** * Avoid obstructions (trees, buildings) * Avoid the **leeward side** of structures * Ensure precipitation can fall freely *** #### Wind Sensors * Install with **minimal obstruction** * Avoid areas where airflow is blocked or channeled * Consider **prevailing wind direction** *** #### Radiation Shield (Temperature / Humidity / Pressure) * Install in **well-ventilated air** * Avoid shaded or enclosed areas * Avoid heat sources (buildings, pavement) *** #### Solar Panel * Ensure **maximum sun exposure** throughout the day * Avoid shading from objects or terrain * Consider seasonal changes in sun angle *** #### Soil Sensors (if installed) * Place in **representative soil conditions** * Avoid artificially shaded or disturbed areas *** ### Balancing Siting Tradeoffs Perfect sites are rare. When compromises are required: * prioritize **rain gauge exposure** * maintain **good airflow** around temperature and humidity sensors * ensure **adequate solar power** Document all siting limitations in station metadata. *** ### Observing Practices and Standards 3D-PAWS follows the [*World Meteorological Organization (WMO) Guide to Instruments and Methods of Observation (WMO-No. 8)*](https://community.wmo.int/site/knowledge-hub/programmes-and-initiatives/instruments-and-methods-of-observation-programme-imop/guide-instruments-and-methods-of-observation-wmo-no-8), which provides detailed sensor exposure and siting recommendations. Applying these principles improves data quality and consistency. *** ### Summary A well-chosen site will: * minimize measurement bias * improve data reliability * reduce troubleshooting needs *** ### Instruction Slides for Site Selection {% embed url="" %} --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://3dpaws.comet.ucar.edu/deploying-3d-paws/site-selection.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.