Drones are a great way to study the effects of climate change or seasonal variation on an ecosystem. But timing your flights wisely is crucial for collecting high-quality, meaningful data. Factors such as sun angle, clouds, wind, and tides can influence your data capture and how to optimize your flight times for the most informative results.

Sun Angle

The angle of the sun can have a significant impact on the quality and usability of your drone imagery. Here are some key considerations:

  1. Shadows: Flying when the sun is low in the sky (early morning or late afternoon) can result in long shadows that obscure features of interest or create false positives in your data. To minimize shadows, aim to fly as close to solar noon as possible, when the sun is directly overhead.
  2. Glare: When the sun is at a low angle, it can create glare on water bodies or other reflective surfaces, making it difficult to accurately capture data in these areas. Flying at higher sun angles can help to mitigate this effect.
  3. Lighting consistency: Consistent lighting conditions are important for comparing data across different flights and time periods. Flying at the same time of day can help to ensure that your imagery has a similar appearance and is easier to analyze.

Clouds

Unsurprisingly, cloud cover can also affect the quality and consistency of your drone data. But it is not necessarily always bad. There are times you may actually prefer cloud cover.

  1. Diffuse lighting: Overcast conditions can provide a soft, diffuse light that minimizes shadows and glare, making it easier to capture consistent imagery across your study area.
  2. Inconsistent illumination: Partly cloudy conditions can create patchy, inconsistent lighting that makes it difficult to compare data between different flights or areas. If possible, try to fly on either completely clear or completely overcast days.
  3. Reduced visibility: Thick cloud cover or fog can reduce visibility and make it difficult to capture usable data. In these conditions, it may be necessary to postpone your flight until the weather improves.

Wind

Wind speed and direction can have a major impact on your drone’s performance and the quality of your data:

  1. Flight stability: Strong winds can make it difficult for your drone to maintain a consistent altitude and flight path, resulting in blurry or distorted imagery. Aim to fly in calm conditions whenever possible, and be prepared to adjust your flight plan if the wind picks up during your mission.
  2. Wind direction: Crosswinds can cause your drone to drift off course, resulting in gaps or overlaps in your data coverage. Plan your flight lines perpendicular to the prevailing wind direction to minimize this effect.
  3. Turbulence: Wind flowing over obstacles such as trees, buildings, or terrain features can create turbulence that affects your drone’s stability and image quality. Be aware of potential turbulence sources and adjust your flight path or altitude accordingly.

Tides

If your study area includes coastal or intertidal zones, the timing of your flights in relation to the tides can be critical:

  1. Intertidal exposure: Flying at low tide can allow you to capture data on intertidal habitats and features that are normally submerged, providing valuable insights into the structure and health of these ecosystems.
  2. Water clarity: Tidal currents can stir up sediment and reduce water clarity, making it difficult to capture usable data in submerged areas. Flying at slack tide can help to minimize this effect.
  3. Tidal influence on vegetation: The distribution and health of coastal vegetation can be influenced by tidal inundation patterns. Flying at different stages of the tidal cycle can help you to capture these variations and better understand the ecosystem dynamics.

Seasonal Variation and Climate Change

When monitoring the effects of seasonal variation or climate change on an ecosystem, consistent flight timing is key:

  1. Phenology: The timing of biological events such as plant flowering, leaf emergence, or senescence can vary from year to year depending on weather patterns and climate conditions. Conducting flights at the same phenological stage each year can help you to track changes over time.
  2. Seasonal differences: Flying at different times of the year can help you to capture the full range of seasonal variations in your study area, from the lush growth of spring and summer to the dormancy of winter.
  3. Long-term trends: Consistently timed flights over multiple years can reveal long-term trends and changes in ecosystem health and functioning that may be related to climate change or other factors.

By carefully considering factors such as sun angle, clouds, wind, tides, and seasonal variation when planning your drone flights, you can collect high-quality, informative data that helps to advance our understanding of ecosystem dynamics and responses to climate change.

The best data for drone mapping missions is often “a lot of it.” So gather as much raw imagery as possible as often as possible. You’ll be surprised what you can learn. And if you’re looking for tips and tricks on how to gather more of that data, check out our master guide to planning and flying successful drone mapping missions.