The connection between GIS and hydrology seems to be very
obvious, as one would easily view GIS as a profoundly useful tool in
water management and modeling systems. Indeed, this person would be correct.
Since the emergence of Geographical Information systems (GIS), we have incorporated it into all aspects of Geology. The use of GIS in water management and modeling
is called hydrological GIS, and this concept primarily pertains to modeling in
the science arena and asset management in the water management arena. However,
while GIS does have very beneficial uses in these areas of academia and
management, its over-application in these social venues can have great
detrimental impact as well. With this in mind, the future of GIS application in
hydrology and water management should be done within a very responsible,
respectful, and professional framework.
Geographical Information Systems use
in modeling hydrology and water sources has been and is very beneficial. Goodchild
(1993) summaries the potential role of GIS in modeling this certain kind of
geology very well, stating its usefulness in “processing data into a form
suitable for analysis; direct support for modeling, so that tasks such as
analysis, calibration and prediction are carried out by GIS itself; and
post-processing data through reformatting, tabulation, mapping and report
generation” (Clark, 1998). These broad uses of GIS are not the limits to its
usage, but instead provide a basic range of roles that it can encompass in
which can now be easily recognized. GIS also has potential to help in asset
management involving water sources as explored by Maidment (1993), proposing
several applications: “Hydrological assessment to represent hazard or
vulnerability; hydrological parameter determination, whereby the GIS provides
inputs to the model in terms of parameters such as surface slope, channel
length, land use and soil characteristics; Hydrological modeling within the
GIS; and linking the GIS and hydrological models to utilize the GIS as an input
and display device” (Clark, 1998). Since the development of GIS, many have promoted
its largely beneficial applications within hydrology and water management and
in practice GIS did seem to be a brand new immensely useful technology.
However, there are many problems that have been investigated as time has moved
forward.
One such problem is the data
quality. Low data quality is a major constraint on the reliability and success
of the hydrological applications of GIS in both scientific and asset management
domains. To better data quality GIS users often work to constantly increase resolution
as much as possible so the data is more detailed and to minimize error.
However, Clark details four significant problems that come with greater
resolution: “Both spatial and temporal resolution carry an overhead of
increasing data volume, with concomitant increases in storage and processing
speed … higher resolution increases the scene noise whereby adjacent pixels
carry different values in response to minor and local changes in ground surface
properties, giving a speckled effect … Many of the features represented in the
GIS model of the real world are by their nature fuzzy and time bound
transitions which are simplified to an increasingly unrealistic rigid and
static spatial representation as resolution increases … In a few high-profile
applications – notably those associated with the insurance market – high resolution
implies a specificity that decreases the unknowns or errors in estimating risk
probabilities” (Clark, 1998). All of these negative factors of increasing resolution
work against creating quality data, except for the last factor. Interestingly
enough, Clark’s statement provides that higher resolution will give more
detailed information and a greater quality of data; however he believes it to
be detrimental to certain venues of Society.
In this forth problem with increasing
resolution, Clark calls upon an example of GIS application in flood insurance
to provide information on how this increasing quality of data can be
detrimental to our asset management systems. Natural hazard insurance calls
upon the idea that the burden of a few will fall lightly on the shoulders of
the many. Insurance clients pay premiums for insurance against natural risks so
that if something is to happen to the client due to natural perils the insurer will pay to help aid the victim in
recovering from their loses. This insurance system is highly effective, but it
relies on a large clientele to receive premiums from in order to have the money
available to help those clients that are in need, as well as make a decent buck.
With this in mind, using GIS with very high resolution to create models to rate
flood probability in different locations of clientele with very good data will make
insurers confident in knowing which clientele are in more risk and who are not.
Obviously the insurer will use this to drop those most at risk or change rates
for different clients depending on risk rating, as to protect and promote their
business. This is why Clarke calls for professional protocols for the future
development of GIS, especially in water management and hydrology, as GIS has
great power in creating change.
This great power of GIS in many
aspects of society can be easily misused and abused. This growing field and its
technologies are capable of transforming understandings, decisions, operations,
the way employees work, the way businesses and professionals relate to their
customers, and plenty of other aspects of society. For this reason, Clark
provides a professional code that should serve as primary standards for GIS
users: “data uses and processing that have been proposed meet corporate mission
standards … ensure equitable and responsible access to information … data
documented in such a way that everyone using them is bound to be aware of their
resolution and other limitations or constraints … data processing techniques
and protocols are so explicit that every user can assess their suitability and
adequacy for the task at hand … established an error-tracking audit to ensure that the system meets explicitly
defined quality targets … asked whether what you are doing is beneficial to the
business, the customer and society?” (Clark, 1998). This professional protocol becomes
the most important message of Clark’s article.
In looking how GIS has been viewed since its beginnings, how
GIS is beneficial to us today and will be useful to us in the future, how GIS
can create problems, and how to mitigate these problems; we begin to understand
the great power in which Geographical Information Systems and related
information technologies command. One should realize, through this exploration
into GIS as a tool in hydrology and water management, that GIS is a very useful
and versatile tool; however, one must also recognize the flaws of the system,
how it can detriment society if used improperly, and the power it holds to
create change. This is why we must adhere to Clark’s list of professional
protocols as we move forward into the future with our GIS technologies, positively
utilizing them with the upmost respect, responsibility, and professionalism.
Clark, M. J. (1998). Putting water in
its place: a perspective on GIS in hydrology and water management. Hydrological
Processes, 12, 823-834. Retrieved from
https://lms.southwestern.edu/file.php/3722/Literature/Clark-1998-Putting_Water.pdf
Clark's professional protocol can be achieved through good use of metadata. Too often GIS Analysts and others using GIS to create data will not make metadata to go along with it. Without the metadata the intended use, accuracy, and resolution is unknown. This can lead to data being miss used. This is why you often see government agencies place an emphasis on creating metadata along side data creation. Unfortunately in common practices, many people don't do it. It is hard enough to get people to names there files properly, let along make metadata. I think the ultimate responsibility falls on the GIS Analyst, to make sure they known where they are getting the data from, and know the limitations of the data before analysis. Finally when creating data for distribution to public be sure to make metadata.
ReplyDeleteIt's interesting that the GIS information can be seen as a detriment to society. I guess all knowledge, used in the wrong way, can be dangerous. Hydrological GIS interests me a lot, I wonder what kinds of field research is necessary to get good enough data to asses possible pollution problems, or if you could get an adequate amount of information from satellites.
ReplyDeleteI'm in the Water in the West FYS, which focuses on increasing the efficiency of water usage and what we're going to do in a water shortage. It's interesting how GIS could be used to monitor water consumption, but even more so that some people view it as a threat. I think GIS could be a marvel for farmers who could benefit from watching how much water is used on their properties. Water prices are only going up, so GIS data could be a great help in - literally - finding the leaks.
ReplyDeleteIt is interesting to look at how GIS is used in hydrology and water consumption and compare it to how some of the same aspects are used in GIS for prediction of forest fires across the United States.
ReplyDeleteAlex, I wanted to like your comment. But alas, we are not on facebook. Water Management seems to me like one of the least discussed issues throughout the country. It sort of seems like Westernized countries think that because we're not a third world country, that there is going to be fresh flowing water from our sinks forever. The current ways we use (more like waste) water, just isn't sustainable. The pipes that carry water from an aquifer (with an ever decreasing water table) lose upwards of a third of the water that is transported. Rainwater collection, for goodness sakes is banned in some parts of the US. There really needs to be more community oriented discussion on preservation of water including rainwater collection (if it's not illegal in your state. Plenty legal in Texas) and recycling greywater by filtration from plants (woah that's epic! Actually not really. That type of filtration has been utilized by humans for many centuries. We've just forgotten very simplistic ways to live with the Earth. Ok, enough ranting).
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