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Introduction to Data Goods

  • What’s a Data Good?
  • Datasets and Data Products Summary

Data Products

  • Damage to Buildings and Infrastructure
    • Visualizing Damage Buildings and Infrastructure in Gaza
    • Damage Assessment until February 2, 2024
    • Damage Assessment until March 17, 2024
  • Nighttime Lights Trends
    • Nighttime Lights Trends in Gaza and West Bank
    • Nighttime Lights Trends in Jordan
  • Gaza Mobility Analysis
    • Activity Trends in Gaza
    • Mapping Activity in West Bank
    • Movement in West Bank Using Mobile Location Data
    • Movement in West Bank Using Mobile Location Data - reduced sample
  • Solar Panel Detection in Gaza
  • Air Pollution in West Bank
    • Air Pollution in the West Bank and Gaza Strip

Sample Indicators

  • Impact on Housing and Community
  • Impact on Industry and Commerce

Acknowledgements

  • Data Goods Team and Acknowledgements
  • Repository
  • Suggest edit
  • Open issue
  • .ipynb

Nighttime Lights Trends in Gaza and West Bank

Contents

  • Data
    • Region of Interest
    • NASA Black Marble
  • Methodology
    • Time Series Generation
      • Weekly
      • Monthly
  • Findings
    • Percent Change in NTL Radiance
      • Benchmark Comparison
      • Week over Week Comparison
    • Point-in-Time Comparison
      • Daily
      • Weekly
  • Limitations
  • References

Nighttime Lights Trends in Gaza and West Bank#

In a world marked by diverse forms of conflict, from armed confrontations to civil unrest, NASA’s Black Marble Nighttime Lights dataset offers an unconventional yet powerful tool for understanding the ripple effects of these conflicts on human settlements and infrastructure. By tracking nighttime light variations and disruptions, we can unearth insights into population displacement, economic destabilization, and the societal impacts of conflict. This analysis explores the potential of a nighttime lights dataset to not only detect areas affected by conflict but also to quantify the extent of its influence on livelihoods and on the economy, providing a valuable perspective on the multifaceted consequences of conflict.

Data#

Region of Interest#

Define region of interest for which NASA Black Marble will be downloaded. We use GADM.

Show code cell source Hide code cell source
PSE = geopandas.read_file("../../data/boundaries/gadm41_PSE_shp/gadm41_PSE_2.shp")
PSE.explore()
Make this Notebook Trusted to load map: File -> Trust Notebook
../../_images/logo.png

Fig. 12 Region of Interest. Country borders or names do not necessarily reflect the World Bank Group’s official position. This map is for illustrative purposes and does not imply the expression of any opinion on the part of the World Bank, conceming the legal status of any country or territory or concerning the delimitation of frontiers or boundaries.#

NASA Black Marble#

NASA’s Black Marble product suite represents a remarkable advancement in our ability to monitor and understand nocturnal light emissions on a global scale. By utilizing cutting-edge satellite technology and image processing techniques, the Black Marble VIIRS dataset offers a comprehensive and high-resolution view of the Earth’s nighttime illumination patterns. To obtain the raster data conveniently and calculate zonal statistics, we use the BlackMarblePy [1] package developed by the World Bank.

VNP46A2 = bm_extract(
    PSE,
    product_id="VNP46A2",
    date_range=pd.date_range("2022-01-01", "2024-06-12", freq="D"),
    bearer=bearer,
    file_directory="../../data/nighttime-lights",
    aggfunc=["mean", "sum"],
)
VNP46A3 = bm_extract(
    PSE,
    product_id="VNP46A3",
    date_range=pd.date_range("2022-01-01", "2024-06-12", freq="MS"),
    bearer=bearer,
    file_directory="../../data/nighttime-lights",
    aggfunc=["mean", "sum"],
)

The latest update date is:

'20 May 2024 (Week 21)'

Important

The VNP46A2 Daily Moonlight-adjusted Nighttime Lights (NTL) Product is available daily. However, due data quality, cloud cover or other factors, the data may not be available always at a specific location.

Methodology#

Creating a time series of weekly radiance using NASA’s Black Marble data involves several steps, including data acquisition, pre-processing, zonal statistics calculation, and time series generation. Below is a general methodology for this process.

Time Series Generation#

Organize the zonal statistics results in a tabular format, where each column corresponds to a specific zone, and rows represent the daily radiance values. Next, we aggregate the data on a weekly basis, computing the desired statistical metric (e.g., mean radiance) for each zone for each week. Finally, we will visualize the time series data to observe trends, patterns, and anomalies over time.

Weekly#

In this step, we compute a weekly aggregation of the zonal statistics by for each second-level administrative division and for each week. In this case, we W-SUN and mean as aggregate function.

Show code cell source Hide code cell source
PSE_2 = (
    VNP46A2.pivot_table(values=[VAR], index="date", columns=["NAME_2"])
    .resample("W-SUN", label="right")
    .mean()
)
PSE_1 = (
    VNP46A2.pivot_table(values=[VAR], index="date", columns=["NAME_1"])
    .resample("W-SUN", label="right")
    .mean()
)

PSE_2
ntl_mean
NAME_2 Bethlehem Deir Al-Balah Gaza Gaza ash Shamaliyah Hebron Jenin Jericho Jerusalem Khan Yunis Nablus Qalqilya Rafah Ramallah and Al-Bireh Salfit Tubas Tulkarm
date
2022-01-02 15.204650 7.979566 13.673667 8.275610 5.509554 4.963882 5.526086 26.562299 12.340092 7.097979 11.070501 NaN 9.829518 14.304472 3.700941 5.659215
2022-01-09 3.937239 13.335583 20.106966 12.400183 6.795771 7.521570 5.598589 21.751601 13.603669 6.986950 17.083686 22.926138 9.664528 15.148751 2.439910 11.244419
2022-01-16 9.067182 11.666783 15.247343 11.185364 4.952166 6.438554 4.494609 29.346998 13.005158 7.004429 14.890246 22.234868 9.463288 12.201209 1.950268 11.332975
2022-01-23 11.885563 13.398174 19.648510 13.627723 6.976829 7.256974 4.372017 22.756302 12.409488 7.997001 17.848442 20.634801 8.747132 13.980935 2.780365 11.759398
2022-01-30 3.984767 10.135582 14.438217 9.784870 4.517948 4.674371 4.451629 18.479181 10.809777 4.882015 12.376466 16.943309 6.506664 10.623585 2.216819 8.362207
... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ...
2024-04-28 6.074798 1.257482 0.924436 1.325919 10.184064 9.597764 5.811190 23.763467 1.138724 15.387921 17.679995 5.051628 12.041718 16.759997 4.398684 11.448836
2024-05-05 5.550352 1.108389 1.063711 1.253645 6.762541 10.182833 6.398982 22.556344 1.110848 5.508794 19.613854 5.144830 7.598836 15.218865 2.940589 15.867287
2024-05-12 9.795301 1.205562 1.064387 1.663202 8.903236 8.700199 5.639193 25.550117 1.246434 9.195792 17.872155 4.142467 10.167407 16.202932 3.778633 13.280829
2024-05-19 7.733241 1.357684 1.200181 1.749396 10.133451 9.494532 6.748175 26.181663 1.416646 9.212635 17.119559 4.926859 10.824513 16.144255 4.115924 13.756627
2024-05-26 1.202895 NaN 1.400000 1.996894 0.514894 19.436765 7.482610 5.031830 NaN 3.494098 17.305063 NaN 3.402216 16.628125 3.655341 NaN

126 rows × 16 columns

Monthly#

In this step, we compute a monthy aggregation of the zonal statistics by for each second-level administrative division and for each month. Additionally, we add the VNP46A3 monthly composite, when available.

Show code cell source Hide code cell source
p = figure(
    title="Palestine: Monthly Nighttime Lights",
    width=800,
    height=600,
    x_axis_label="Date",
    x_axis_type="datetime",
    y_axis_label=r"Radiance [nW $$cm^{-2}$$ $$sr^{-1}$$]",
    tools="pan,wheel_zoom,box_zoom,reset,save,box_select",
)
p.add_layout(
    Title(
        text="Monthly NTL Radiance Average (VNP46A2 and VNP46A3) for each second-level administrative division",
        text_font_size="12pt",
        text_font_style="italic",
    ),
    "above",
)
p.add_layout(
    Title(
        text=f"Data Source: NASA Black Marble. Creation date: {datetime.today().strftime('%d %B %Y')}. Feedback: datalab@worldbank.org.",
        text_font_size="10pt",
        text_font_style="italic",
    ),
    "below",
)
p.add_layout(Legend(), "right")

p.add_tools(
    HoverTool(
        tooltips=[
            ("Month", "@x{%B %Y}"),
            ("Radiance", "@y{0.00}"),
        ],
        formatters={"@x": "datetime"},
    )
)

for column, color in zip(PSE_2_MS.columns, cc.b_glasbey_category10):
    r = p.line(
        PSE_2_MS.index,
        PSE_2_MS[column],
        legend_label=column[1],
        line_color=color,
        line_width=2,
    )
    r.visible = False

    # Except Gaza visible
    if str(column[1]) == "Gaza":
        r.visible = True

for column, color in zip(VNP46A3.columns, cc.b_cyclic_grey_15_85_c0):
    r = p.line(
        VNP46A3.index,
        VNP46A3[column],
        legend_label=column[1],
        line_color=color,
        line_width=2,
    )
    r.visible = False

    # Except Gaza visible
    if str(column[1]) == "Gaza":
        r.visible = True

p.legend.location = "bottom_left"
p.legend.click_policy = "hide"
p.title.text_font_size = "16pt"

output_notebook()
show(p)
Loading BokehJS ...
../../_images/logo.png

Fig. 13 Monthly NTL radiance average derived from the VNP46A2 daily composite and, in grey, derived from the VNP46A3 monthly composite.#

Findings#

Percent Change in NTL Radiance#

Benchmark Comparison#

In this exploratory analysis, we conducted analysis of NTL radiance trends, comparing the observed average radiance levels to a benchmark established in the year 2022 for each second-level administrative division.

Show code cell source Hide code cell source
PERCENTCHANGE_2 = 100 * (
    PSE_2 / PSE_2[(PSE_2.index >= "2022-01-01") & (PSE_2.index < "2023-01-01")].mean()
    - 1
)
PERCENTCHANGE_1 = 100 * (
    PSE_1 / PSE_1[(PSE_1.index >= "2022-01-01") & (PSE_2.index < "2023-01-01")].mean()
    - 1
)
  ntl_mean
NAME_2 Bethlehem Deir Al-Balah Gaza Gaza ash Shamaliyah Hebron Jenin Jericho Jerusalem Khan Yunis Nablus Qalqilya Rafah Ramallah and Al-Bireh Salfit Tubas Tulkarm
date                                
2023-10-01 00:00:00 -1.036671 -5.176193 -0.948034 17.169726 23.825427 16.148794 9.146616 13.155429 5.240423 23.910822 -1.683530 6.814338 13.958437 5.481153 36.628251 1.838384
2023-10-08 00:00:00 -15.460339 -23.601012 -13.217521 0.406629 22.502522 16.334702 23.188619 -18.918551 -19.251201 -0.126586 89.428368 -5.461336 4.527483 4.096273 47.435447 14.639749
2023-10-15 00:00:00 -28.738148 -84.990641 -84.737613 -86.295170 7.023393 16.103461 5.234816 -8.937742 -79.475160 5.182328 0.334092 -74.805776 8.362368 6.216823 10.471731 -7.134540
2023-10-22 00:00:00 2.589614 -87.887605 -85.547573 -84.462721 24.019213 12.939151 17.272591 10.637407 -85.656930 14.411997 9.635253 -76.231608 15.861381 10.029488 27.968269 4.552786
2023-10-29 00:00:00 -33.228641 -84.899959 -71.589192 -79.416537 4.373666 26.021092 22.101463 -38.325125 -78.758188 23.409007 22.102664 -68.939893 43.618721 17.616197 60.568520 12.916775
2023-11-05 00:00:00 31.840591 -83.361935 -67.098409 -72.989751 31.952400 37.854614 16.826575 7.884103 -76.806715 34.922472 21.287162 -69.797142 28.694115 24.666196 48.756274 18.704953
2023-11-12 00:00:00 10.707432 -88.084733 -87.231798 -83.939566 42.284195 31.523291 12.808116 -7.058684 -85.121654 19.730373 -1.670999 -59.688891 11.526984 29.536354 31.652622 4.416223
2023-11-19 00:00:00 -6.505106 -90.766412 -93.044013 -76.097455 8.970045 7.808694 7.312537 13.671693 -88.850664 -4.307680 30.739551 -77.345904 25.492468 22.829905 18.466171 26.871471
2023-11-26 00:00:00 2.140390 -89.456731 -92.147935 -68.865171 17.400668 23.082116 18.250061 -5.227394 -87.328199 27.286106 16.763595 -75.145923 20.816810 12.390030 27.676013 3.721364
2023-12-03 00:00:00 10.755868 -92.292800 -90.129065 -49.735730 16.125376 19.255460 10.091243 -4.122347 -89.900947 5.306588 22.665316 -74.880719 -1.620467 37.791856 17.148207 -1.032048
2023-12-10 00:00:00 -27.778308 -92.140833 -94.562775 -84.613779 4.731970 0.929518 -1.824031 -16.815768 -88.865193 -30.247339 -3.611129 -75.155288 -4.995364 -0.336748 -17.544758 -25.185401
2023-12-17 00:00:00 -29.911173 -92.699088 -88.513792 -92.291638 16.411687 9.431974 -7.279328 6.723104 -91.595629 21.335252 14.573100 -80.577965 14.733637 7.719694 6.936723 2.147263
2023-12-24 00:00:00 3.496513 -92.941141 -92.821373 -87.835807 6.721346 8.402330 45.399533 -1.798316 -91.398088 -7.664691 -2.114718 -75.675966 9.084756 3.927569 4.985050 -6.837770
2023-12-31 00:00:00 -5.615821 -96.182853 -94.691191 -90.584846 20.687287 -3.763185 -3.150697 -2.323018 -93.149418 15.829027 7.898747 -78.339729 14.595065 11.681975 -6.643506 2.076317
2024-01-07 00:00:00 4.855568 -83.911092 -93.231731 -91.521645 16.247743 3.651775 6.777407 4.492586 -91.297112 35.514281 15.355475 -79.821942 6.402212 6.018695 22.873217 -12.465832
2024-01-14 00:00:00 -35.579987 -85.773887 -95.520273 -91.725524 -15.689690 -15.200722 -3.518413 -0.000636 -90.713913 0.391955 -9.253621 -76.165399 -16.729773 -9.999947 9.459606 -10.988212
2024-01-21 00:00:00 -0.429245 -94.771595 -96.836293 -94.789532 16.970415 5.488577 -6.218441 12.216378 -92.849302 11.206870 -7.501423 -77.890989 11.704396 3.039164 -9.231834 1.460175
2024-01-28 00:00:00 -42.232540 -85.472312 -96.674364 -93.328954 -27.160916 -4.874859 -8.097918 -10.169709 -92.251955 -16.373157 -12.832538 -71.747311 -16.124229 -9.685026 23.361902 -6.113997
2024-02-04 00:00:00 9.624986 -92.215109 -95.482371 -92.813473 -5.284329 19.754285 -4.583077 -30.059455 -91.163749 -9.849854 -47.698255 -76.615209 8.406231 -24.210245 -1.455732 -28.290060
2024-02-11 00:00:00 -2.208070 -93.046532 -96.028273 -94.013547 -4.020676 1.966128 3.907424 5.878637 -92.265132 6.067368 1.178348 -78.204530 3.633536 3.530960 4.767811 -2.063339
2024-02-18 00:00:00 -55.743287 -93.952992 -96.301815 -93.578913 -32.919641 -7.368794 -4.669525 -33.364878 -93.474321 -36.454310 -4.566208 -74.842105 -32.753634 -23.402388 -5.666674 -15.914364
2024-02-25 00:00:00 -2.624561 -95.147442 -97.621454 -95.161931 -0.227732 -5.818200 -8.906716 14.948958 -93.419818 -16.381130 -12.154129 -78.733216 -6.042581 -11.283703 -0.360697 -2.153483
2024-03-03 00:00:00 1.778810 -94.467515 -96.253669 -94.617306 0.692269 4.832337 -0.313592 -7.838997 -93.098037 11.099617 0.276708 -81.748487 3.325169 -3.329444 -6.049322 -4.561845
2024-03-10 00:00:00 -12.953243 -92.074729 -94.183374 -91.673758 11.253326 4.275844 13.831881 2.110992 -91.982509 -8.576286 7.575784 -79.437321 1.315940 9.091632 -2.344244 -4.587345
2024-03-17 00:00:00 36.857234 -90.654246 -95.836588 -93.021142 46.025212 21.581473 13.909510 34.778611 -89.950485 8.031213 14.886133 -78.774130 23.605227 19.411565 12.096730 4.440915
2024-03-24 00:00:00 -34.093426 -94.900709 -97.297526 -94.841791 -24.156188 12.551742 1.498461 -2.533256 -94.109888 -9.569838 7.191016 -69.716194 -9.298569 8.996637 -1.793148 11.011614
2024-03-31 00:00:00 19.192082 -94.286901 -96.988700 -93.656006 42.019527 18.785799 21.232726 5.063069 -93.753087 19.550572 -0.882823 -78.500020 15.817070 10.793058 8.509295 1.274878
2024-04-07 00:00:00 -0.367979 -90.724515 -95.224080 -91.661899 37.387269 32.229789 33.149438 10.708738 -90.983706 16.710475 19.382020 -77.539062 16.833683 22.999943 25.704990 26.932911
2024-04-14 00:00:00 -0.763891 -91.823202 -95.068143 -91.995526 28.239395 8.862055 29.763376 12.602952 -92.266703 48.085788 -1.997900 -82.475067 5.746653 0.990472 18.533820 -3.168056
2024-04-21 00:00:00 4.832880 -90.591483 -95.779500 -91.995027 11.192319 14.640409 14.032182 9.951929 -92.192110 -8.025892 28.238068 -79.008976 16.819730 16.626814 4.293898 5.439511
2024-04-28 00:00:00 -13.294790 -90.060797 -95.720179 -91.151924 32.714213 25.022696 6.874366 0.150687 -91.170454 92.762857 9.440095 -75.595225 28.352535 16.822219 43.246163 -5.577958
2024-05-05 00:00:00 -20.780186 -91.239235 -95.075384 -91.634214 -11.873565 32.643945 17.684540 -4.936709 -91.386598 -30.991927 21.410787 -75.144958 -19.004093 6.080065 -4.237705 30.862349
2024-05-12 00:00:00 39.807697 -90.471171 -95.072257 -88.901173 16.023020 13.330811 3.711148 7.680490 -90.335278 15.194711 10.629580 -79.987448 8.374275 12.939307 23.053780 9.531048
2024-05-19 00:00:00 10.376057 -89.268790 -94.443575 -88.325987 32.054646 23.677979 24.106595 10.342130 -89.015468 15.405694 5.970969 -76.197990 15.378359 12.530316 34.037920 13.455100
2024-05-26 00:00:00 -82.831161 nan -93.518483 -86.674390 -93.290135 153.187805 37.613682 -78.793445 nan -56.229801 7.119251 nan -63.735818 15.903033 19.038712 nan

Now, let’s visualize the plot.

Show code cell source Hide code cell source
show(create_plot(PERCENTCHANGE_2))
../../_images/logo.png

Fig. 14 Weekly percent change (compared to 2022 benchmark) in NTL radiance (VNP46A2) for each second-level administrative division.#

Additionally, we visualize below the NTL radiance average on first-level administrative division.

../../_images/logo.png

Fig. 15 Weekly percent change (compared to 2022 benchmark) in NTL radiance (NASA Black Marble VNP46A2) for each first-level administrative division.#

Week over Week Comparison#

In this exploratory analysis, we conducted analysis of NTL radiance trends, comparing the observed average radiance levels week over week (WOW) for each second-level administrative division.

Show code cell source Hide code cell source
WOW_2 = 100 * (PSE_2.pct_change(1, axis="rows", fill_method=None))

Point-in-Time Comparison#

Daily#

../../_images/pse_ntl_VNP46A1_2023-01-01.png

Fig. 16 Nighttime lights on January 1, 2023. Source: NASA Black Marble (VNP46A1).#

../../_images/pse_ntl_VNP46A1_2023-10-21.png

Fig. 17 Nighttime lights on October 21, 2023. Source: NASA Black Marble (VNP46A1).#

Weekly#

We visualize below weekly snapshots of the percent change (compared to 2022) in NTL radiance average for each second-level administrative division.

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Limitations#

Using nighttime lights to estimate macroeconomic indicators during conflict may be a valuable approach, but it comes with several assumptions and limitations. Here’s a list of some of the key assumptions and limitations:

Caution

Assumptions:

  • Luminosity Reflects Economic Activity: The approach assumes that the level of nighttime lights is a reliable proxy for economic activity. It presupposes that areas with brighter lights correspond to higher economic productivity.

  • Baseline Data Availability: It assumes the availability of baseline nighttime lights data before the onset of the conflict. The accuracy of the estimates depends on the quality and relevance of this baseline data.

  • Spatial Distribution: The method assumes that nighttime lights are evenly distributed within a given geographic area and that changes in luminosity accurately reflect changes in economic activity across all locations.

Limitations:

  • Confounding Factors and Data Interpretation: The approach may require subjective interpretation, as it may not distinguish between reduced lighting due to conflict and reduced lighting due to other factors. Changes in nighttime lights can be influenced by factors other than economic activity, such as energy conservation measures, urban development, or seasonal variations.

  • Generalization: The approach might lead to overgeneralization, as a reduction in nighttime lights can be associated with various economic outcomes, from minor disruptions to severe economic downturns.

  • Alternative Explanations: Changes in nighttime lights can result from factors other than conflict, such as urban development, changes in economic activities, or natural disasters. Therefore, it may not always be clear whether a decline in nighttime lights is solely due to conflict.

  • Geopolitical Factors: The dataset may be subject to geopolitical biases, with some areas having less comprehensive coverage due to political reasons.

  • Data Lag: There can be a significant time lag between the occurrence of a conflict event and its reflection in the nighttime lights dataset. This lag may limit the dataset’s utility for real-time conflict monitoring.

  • Resolution and Urban Bias: The dataset’s spatial resolution may not be fine enough to capture small villages or isolated conflict events. It may also have an urban bias, making it less suitable for analyzing rural or remote conflicts.

To address these assumptions and limitations, it is crucial to complement nighttime lights data analysis with other sources of information and adopt a cautious and context-aware approach when interpreting the findings.

References#

1

Miguel O. Román, Zhuosen Wang, Qingsong Sun, Virginia Kalb, Steven D. Miller, Andrew Molthan, Lori Schultz, Jordan Bell, Eleanor C. Stokes, Bhartendu Pandey, Karen C. Seto, Dorothy Hall, Tomohiro Oda, Robert E. Wolfe, Gary Lin, Navid Golpayegani, Sadashiva Devadiga, Carol Davidson, Sudipta Sarkar, Cid Praderas, Jeffrey Schmaltz, Ryan Boller, Joshua Stevens, Olga M. Ramos González, Elizabeth Padilla, José Alonso, Yasmín Detrés, Roy Armstrong, Ismael Miranda, Yasmín Conte, Nitza Marrero, Kytt MacManus, Thomas Esch, and Edward J. Masuoka. Nasa's black marble nighttime lights product suite. Remote Sensing of Environment, 210:113–143, 2018. URL: https://www.sciencedirect.com/science/article/pii/S003442571830110X, doi:https://doi.org/10.1016/j.rse.2018.03.017.

2

Gabriel Stefanini Vicente and Robert Marty. BlackMarblePy: Georeferenced Rasters and Statistics of Nighttime Lights from NASA Black Marble. February 2024. URL: https://doi.org/10.5281/zenodo.10667925, doi:10.5281/zenodo.10667925.

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Nighttime Lights Trends in Jordan

Contents
  • Data
    • Region of Interest
    • NASA Black Marble
  • Methodology
    • Time Series Generation
      • Weekly
      • Monthly
  • Findings
    • Percent Change in NTL Radiance
      • Benchmark Comparison
      • Week over Week Comparison
    • Point-in-Time Comparison
      • Daily
      • Weekly
  • Limitations
  • References

By Development Data Group

Last updated on Mar 31, 2025.

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