Pilot Study on Biosphere-Atmoshphere Interaction in Dhofar

Pilot Study on Biosphere-Atmosphere Interaction in Dhofar

(the GIS component thereof)

Update (June 10, 2003) – Readme file provided with Dhofar GIS ver.1.0 is accessible here.

It is serves as an overview of the dataset formats and processing, tools developed,

and the Dhofar GIS ver.1.0 environment.

Posted on January 17, 2004

Prelude

This document outlines the key factors shaping the selection, development, and assembly of a proposed Geographic Information System (GIS) to support the ongoing Pilot Study on Biosphere-Atmosphere Interaction in Dhofar. After a concise description of the Dhofar region, the ecological threat it faces, and the global objectives of this Pilot Study, we delve into spelling out: the need for a GIS, a survey of system alternatives, the major development milestones foreseen at this point, and the end-goal(s) the system would serve; all the way from being an indispensable spatial analysis tool to helping in communicating results to the lay public. A listing of the various datasets we expect to normalize and assimilate is also presented.

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Contents

Prelude.. 2

Contents.. 3

Background Information.. 4

About Dhofar (facts & figures)

Ecological Threat

Pilot Study: Global Objectives

GIS Component. 6

Needs to Serve

Survey of Alternatives

System Development and Assembly

Datasets

Conclusive Summary.. 12

References.. 13

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Background Information

About Dhofar (facts & figures)

Dhofar is a southern province in Sultanate Oman and accounts for almost 50% of the country’s land mass. Dhofar stretches from Ra'su sh-Sharbatat (East) till the border with Yemen (West), and has an estimated 200,000 inhabitants, with Salalah as its only major city. It is the Salalah plain (65km long, varying between 1.5 and 10km in width), running along the coast of the Arabian Sea, which is of real importance in Dhofar. The Salalah plain is the only part of the Arabian Peninsula that is touched by the monsoon (between the months of June and September), yielding flowing streams throughout the year and much needed moisture in this desert region. These regular summer rains have, over countless centuries, softened the peaks of the Dhofar Mountains (the Jebel Qara) resulting in gentle rolling uplands, quite unlike anywhere else in Arabia.

Dhofar is the most vital agricultural area of Oman, and its produce includes coconuts, bananas, sorghum, alfalfa, vegetables, as well as cattle for milk and meat. The most famous product of Dhofar, however, is frankincense.

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Ecological Threat

Despite its lush nature that undoubtedly stands out in this generally arid region, Dhofar faces a pronounced ecological threat due to its ever-increasing livestock that is overgrazing the area to the detriment of its vegetation. With the discovery of petroleum in Oman, domestic riches have been accumulating over the past half century, and translating into added cattle and farm animals. Traditionally, wealth is reflected by the amount of livestock one owns in Arabia, and hence the direct correlation between the two.

However, the overly increasing amounts of livestock are impoverishing the grassland of the Salalah coastal plain, and most importantly, threatening the trees on the Jebel Qara slopes. Those high-rising trees are renowned for intercepting incoming clouds that source the area’s much needed moisture and rainfall, and currently reflect the major sign of regional deforestation.

Pilot Study: Global Objectives

Studying the biosphere-atmosphere interaction in Dhofar ultimately aims at: (1) discerning the natural influence and human potency on the ecosystem in Dhofar, and (2) justifying different combat strategies that would prevent deforestation in the area, and help Dhofar retain its unique natural resources/beauties.

After a larges scale climate analysis (wind, pressure, sea surface temperature, etc…) and local study on the climate in Dhofar, an atmospheric model was set up for the region to simulate the local climate and help study its influence on the ecosystem. Shortly, the effect of human activity on the system will be also incorporated, after which the full-fledged system can be used to infer correlations and develop long-term strategies that would hinder the otherwise inevitable desertification problem in Dhofar.

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GIS Component

Needs to Serve

Developing a GIS component to complement this Pilot Study would support the project through: (1) serving as an inventory of all spatial data pertaining to the study, (2) facilitating spatial analysis, querying, visualization, and correlation-lookup to help reach/justify the conclusions to be made, and (3) easily conveying technical results to the lay audience and involving the public in the decision making process.

At the lowest level of effort, a GIS can be used to supply inventory information to the Dhofar Pilot Study. The presence or absence of a given vegetation cover or rainfall event, or change in these variables on a spatial basis, can be valuable in studying the influence of natural phenomena on the ecosystem in Dhofar. That is, the capability to store, quantify, and present data on a spatial basis is an inherent characteristic of any GIS.

At the highest level of technology, the GIS can provide a spatial database of information to support modeling of the phenomena under study. The GIS will supply the spatial data in a form that can be inputted into deterministic or statistical models. The spatial power of the GIS database is used in full by the model, and more detailed and spatially averaged results are produced. This represents a high level of integration and achievement that the Pilot Study would want to ultimately aim at, and hence the need for a normalized easily-expandable system that can be seamlessly upgraded and built on once the original developers leave.

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Survey of Alternatives

The capabilities and costs of different GIS software vary greatly from vendor to vendor and the decision on what software to use depended on: (1) the format of the original/raw data available to us and the necessary effort required to have it comply with the different GIS software options, and (2) the end objectives our GIS is employed to ultimately serve.

The following factors have been considered before deciding on the GIS software we eventually adopted:

· Data input and editing functions

· Analysis functions

· Flexibility of the system (compatibility with other software and hardware)

· Availability to us through in-house sources

· Cost to purchase, operate, and maintain the system

The GIS-focused product vendors we considered were: ArcInfo, MapInfo, Integraphy, and GRASS; whereas the more image processing-focused product vendors were PCI, ERMapper, ENVI, ERDAS, and IDRISI. We finally settled on ESRI’s ArcInfo for the following reasons:

· ESRI is the GIS market and technology leader

· ESRI sets up most industrial standards

· ArcInfo combines powerful functions in both vector and raster processing

· It offers many off-the-shelf mathematical models

· It provides the mathematical foundation to further develop simulation models

· The datasets considered so far (like the TRMM dataset, for instance) can be exported into native ArcInfo data format

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System Development and Assembly

Upon selecting the system to be used, development begins with preparing the GIS environment and importing the first set of maps, coverages and/or datasets. As for the development roadmap, we see the GIS system evolving through the following stages:

· Data acquisition: collect data from USGS, NASA, TRMM, NGOs, climate stations, etc…

· Data pro-processing: all kinds of data need to be converted into ArcInfo data formats

· Spatial mathematical models development: to support basic overlay analysis, buffering, and natural phenomena modeling (simulation and predictive)

· Interactive simulation interface development: using ‘thematic’ maps and stored procedures/queries enabling instant graphical visualization of analysis results

To emphasize the last milestone, a particularly valuable use of a GIS is in project presentations. The managers or decision makers on any project appreciate the quantitative information derived from GIS analysis. Naturally, they also appreciate the high quality graphical products that support the project, and demonstrate the results of project analysis. Furthermore, this is appropriate for public meetings and audiences beyond our immediate group. Describing current climatic conditions and justifiably specifying deforestation strategies involve a wealth of information, and GIS products can help visually represent this information in the form of variables that must be weighed to make a decision. The GIS displays will also help lead the audience/officials in Oman through the same decision-making process, and help lend insight into the results of our analysis and recommendations. Such maps are far more readily-interpreted than tabular data alone, which has historically been a major effort and time consuming component of data analysis.

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Datasets

Spatial data is the life-blood of any GIS, and we expect that somewhere between 80% and 90% of the time, effort, and money required to run our GIS will be invested in acquiring, processing, normalizing, inputting, and manipulate data. A comprehensive study of the natural and human activity influence on the Dhofar ecosystem cannot be complete in the absence of an as comprehensive range of datasets traversing the different key parameters. This diversity of datasets is summarized in a table (below).

(Please not that this is a tentative list, as we have not been fully acquainted with all the project requirements and data specifications. The other additional/possible datasets are listed in the end.)

Topography (elevation, slope, etc…)
§ From USGS § GTOPO30 format § Precision: 1 kilometer § Consist of: DEM, HDR, DMW etc.
Vegetation
§ Normalized Difference Vegetation Index § NOAA/NASA AVHRR § Binary formats § Precision: 8km § 1985-present
Wind
§ NOAA-CIRES climate diagnostics center § Precision: 2.5 degree § 1948-present
Pressure
§ NOAA-CIRES climate diagnostics center § Precision: 2.5 degree § 1948-present
Sea Surface Temperature
§ UK Meteorological Office § Precision: 1 degree § 1871-present
Precipitation (and possible cloud data)
§ TRMM (Tropical Rainfall Measurement Mission) § Precision: 0.25 degree § 1998-present
Other datasets would/might cover: § Soil § Cloud