Discussion

Nightlight Data

The nightlight data for each study area and Syria as a whole has one overwhelming conclusion: average nightlight value has decreased every year since 2010 in dramatic amounts. Ar-Raqqa and Aleppo experienced the largest decreases in nightlight intensity. The average nightlight value for the years 2010-2013 are plotted in Figure 1 and percent decrease in average nightlight value between years 2010-2013 is shown in Figure 2. The change detection map shows that only extremely limited areas experienced a net gain in nightlight intensity since 2010. The loss in nightlight intensity may be attributed to infrastructure damage that has occurred during the war, ISIS strategy, or ISIS not having access to the Syrian power grid. It could also be due to a loss of population since the war, leading to less energy use overall. A particular reason or a combination of these reasons is difficult to conclude due to a lack of demographic data or public knowledge on ISIS regime strategy.

Syria DMSP nightlight change from 2010 to 2013.

FIGURES

Figure 1: Average DMSP nightlight change from 2010 to 2013 for each study area. Nightlight intensity is measured on a digital number scale from 0 to 63, with 63 being the most intense. An overall pattern of loss is shown.

Figure 2: Percent change in average DMSP nightlight change from 2010 to 2013 for each study area. Nightlight intensity is measured on a digital number scale from 0 to 63, with 63 being the most intense. An overall pattern of large loss is shown.

Figure 3: A table showing the percent of area found in each study region that falls into which change detection category, using the NDVI change detection dates shown in the results page.

NDVI Change Detection Data

After performing analysis in Syria meaningful and significant changes were identified. Impacts were clearly displayed in changes in NDVI around Lake Assad, Tadmor, and Ar-Raqqa.

Lake Assad saw a dramatic loss in greenness in the fields and agricultural sector surrounding the lake. There is a multitude of reasons for such a change, the most obvious answer would be due to the war and the land use change stemming from the fighting. Another reason could be due to the flight of the farmers and those working the land trying to escape the violence brought about from the conflict. Another answer to why plant greenness has diminished is the drought that has gripped the region for years. This drought is almost certainly playing an important role in both the conflict as well as the agriculture of the region. We were able to find clear imagery that shows a large change in NDVI change using data downloaded from GLOVIS. The NDVI change detection results for each study area can be viewed in Figure 3 below.

Issues

Some issues arose in the process of data acquisition. In our data acquisition from GLOVIS, the cloud cover made it so Tadmor and Ar-Raqqa/Lake Assad analysis was performed on different months, potentially leading to some variability in the scales for our NDVI change. In our nightlight analysis there were issues regarding the availability of imagery for certain dates. The DMSP imagery was only available until 2013, so the analysis done with that dataset is pertinent to the Syrian Civil War, but not specifically ISIS occupation. This is where the VIIRS data was helpful, but none was available for 2016. In general, there are serious limitations when working with Syria as a study area, because there is very little data available in regards to demographics. It is difficult to verify findings with first hand accounts and imagery from the fields and from the cities. The instability in the region is an issue for data collection and verification.

Similar Findings

Our findings are consistent with the findings of Xi Li & Deren Li from the University of Wuhan who published similar studies. Our exact parameters for analysis were slightly different but the general trends were consistent between the two projects, namely that Syrian night time lights were found to be diminished by at least 60% between the years 2008 to 2014 (Li & Li, 2014). In the paper "Detecting 2014 Northern Iraq Insurgency using night-time light imagery" by Li et al. it was found that nightlights in Northern Iraqi urban cities had diminished between 16% and 93% after ISIS offensives in 2014. A paper entitled "Holidays in lights: Tracking cultural patterns in demand for energy services" (2015) by Román and Stokes validated the use of VIIRS data in tracking changes in nightlight usage.

Limitations and Future Avenues of Research

Some of our limitations on this project involve our inability to eliminate variables as to why the change we found is occurring. It is not possible at this point to establish causation between ISIS and the effects we noticed. In future research endeavors we could expand the scope and scale of this project in two ways. First a more robust time scale could be analyzed. By looking at more months a more robust model for the NDVI change within Syria could be created to help account for seasonal variations. Determining if this change is gradual or dramatic could help to pinpoint causes of the change as well as predicting the severity of the change into the future. The effects of exact ISIS offensives or actions by foreign militaries could be identified if a more detailed time scale were to be used. A second method to expand the scope of the project would be to do NDVI analysis of the neighboring countries that share similar climate and agricultural conditions. This would allow us to control of the chaos and variability of the civil war currently happening in Syria. However it is hard to completely control the regional instability. Understanding the changes in the agriculture of the region is important for ensuring food security and preservation of the local ecosystems.

This broadening of the scale of the project should be extended out to expanding the nightlight analysis. We should be able to find whether the power shortages are limited to just Syria or if this phenomenon is a regional issue. It would be nice to analyze the power infrastructure to further understand what is truly happening. Whether it is the destruction and deterioration of the entire power grid or whether energy is being funneled away from private use for lights and towards other projects. The dramatic loss of nightlights found in our study along with other published papers leads to questions of public health, food security, and human rights violations.