Vaisala Energy Support
Why do we show a +/- next to the annual value?
The annual mean wind speed value we provide is our best estimate of the actual mean value. The +/- (plus or minus) symbol indicates that the true annual mean value is within a range plus or minus the number shown after the provided wind speed value. The Prospecting Tools directly incorporate a confidence interval for the annual mean wind speed data, showing a range of expected wind speed values, to provide a realistic assessment. We are 68% confident that the true annual mean wind speed for a given location falls inside the displayed range. The narrower the range of wind speeds, (i.e. the smaller the +/- value we show) the more confidant we are concerning the long-term annual mean wind speed value.
For any location, the annual mean range is only meant to be used at the prospecting stage and doesn’t present the full story of a potential site. Data on annual and diurnal variability, prevailing wind direction, and many other atmospheric factors are necessary to more accurately assess the wind resource at any given location.
More Wind Online Tools Questions
- Which Wind Time Series dataset should I choose?
- How do I enter a location?
- How do I interpret the graph provided by the Monthly Mean Wind Speed Tool?
- What does the Annual Mean Wind Speed Tool provide?
- How do I interpret the wind rose provided by the Annual Mean Wind Rose Tool?
- What does the Wind Speed Distribution Tool provide?
- What wind speeds are shown on the map?
- How can I compare sites side-by-side?
- What affects wind at a given site?
- What is a hub height?
- How do I change locations for individual tools?
- What makes a good wind resource?
- What do the colors on the map mean?
- What is the source of the information?
- How accurate are the Wind Prospecting Tools?
- Why does the map disappear?
- How was the 5 km global wind dataset created?
- Does 3TIER incorporate observational data?
- What were 3TIER's data validation procedures for the 5 km global wind dataset?
- What happened to 3TIER’s Reference Wind Time Series Product?
- Why do all the various datasets have different start and end times?
- Doesn’t horizontal resolution matter? What about downscaling with weather models like WRF and MM5?
- Why are the long-term mean values of each data set so similar and why don’t they match the values I get when I download these data directly from the various global modeling centers?
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