How long is the tail of hydrometry?
A solution for the gap between data availability and the impacts of water variability, across all scales of interest, on people and the environment is needed. One of my great hopes for the development of OGC standards for interoperable hydrometric data is that it will shed light on the dark data under the long tail of hydrometry. It is my opinion, unsubstantiated by quantitative surveys, that there are far more hydrometric data out there than are readily accessible from the major hydrometric data providers.
There are more projects with fewer than 10 gauges than there are agencies running more than 10,000 gauges. How many more: one hundred times; one thousand times; ten thousand times? Most of our accessible data are from the large national hydrometric programs – it is difficult to discover the size of the total data potential.
Hydrology is location-based.
There is no ‘ideal’ density for a hydrometric network. More data are always better because even closely placed gauges can represent quite different scaling, climatic, anthropogenic (e.g. effect of extractions, dams, diversions), and landscape processes. Hydrologic misfortune is too often a result of sole reliance on synoptic scale monitoring to predict hydrologic variability at a local scale for planning and management decisions. If you need to understand water at a local scale you need data at a local scale.
This need is largely met by project-specific monitoring done at a very small scale, often by independent stream hydrographers running a handful of gauges. These hydrographers do not have ready access to the resources of the large data providers for data management, archive and dissemination resulting in data that is unsearchable, undiscoverable and inaccessible. As a result this data tends to be collected, often at some considerable expense, for one-time use.
Re-use of such data could greatly expand our ability to understand and manage hydrological variability across all scales of interest. Data re-use implies effective metadata management. Evaluation of ‘fitness for purpose’ for 3rd party use of data requires relevant, reliable and trustworthy information about the data.
Quantifying the size of the opportunity for increasing our global hydrometric data asset is a daunting task.
I would like to get at least a small sense for this opportunity with an informal survey of readers of this blog.
Please take a few moments to answer few questions:
A simple conversation about the opportunity to make the most of our global hydrometric data investment seems like a good place to start.
There will be no cost to participate in the WebEx teleconference, which I will schedule for some time in late September. If needed, the teleconference might be in two parts to accommodate diverse time zones.
The readers of this blog might be just the right group of people to start the conversation.
Please pass the link to this post along to any colleagues who you believe are knowledgeable about the problem and/or who should be part of the solution.