Heatwave Detection in Bangkok, Thailand

[pinkychow1010]

What is the objective of the proposed tutorial?

This tutorial is inspired from the on-going heatwaves in Thailand, which leads to increasing death tolls. It aims to demonstrate how historical heatwave detection and near-real-time monitoring can be performed using temperature data from MODIS.

1. Extract time series anomalies of land surface temperature (LST) in Bangkok.
2. Apply a moving window to the image to detect consecutive hot days.
3. Utilize a multiline plot to visualize temperature anomalies.

What is the scope of the proposed tutorial?
Urban Heat, Heatwaves, Extreme Weather, Thailand

Please provide an outline of the structure of the proposed tutorial?

1. LST Time Series Analysis
   a. Extract MODIS LST data
   b. Apply moving window to temperature time series
   c. Calculate monthly temperature threshold for heatwave detection
2. Data Visualization
   a. Example visualization in map
   b. Multiline chart for heatwave detection

In what format will you be submitting the tutorial?
Markdown

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[jdbcode]

I think this is great, @pinkychow1010 - thanks!

An initial comment - I wonder about using VIIRS LST instead of MODIS LST though... since MODIS will be decommissioned at the end of next year. I think this is roughly the equivalent VIIRS LST data: https://developers.google.com/earth-engine/datasets/catalog/NOAA_VIIRS_001_VNP21A1D

What do you think?

https://www.earthdata.nasa.gov/learn/articles/modis-to-viirs-transition

[pinkychow1010]

Thanks for replying, I have a look into the dataset and I have two concerns about the VIIRS LST data. First, I found the latest data is only available until 01 Mar 2024, so a large time gap, making near-real-time monitoring not possible.

Secondly, I run the algorithm using VIIRS data, and while the MODIS LST (I am looking at Bangkok) match well with the weather data online, VIIRS give me at least 10 degree higher than the records... making the results of detection highly implausible. I am not aware that the VIIRS LST need any offsets, so I do not know yet why is it the case.

[jdbcode]

Okay, thanks for looking into VIIRS as an alternative. I think you should continue with MODIS and in the text, just mention something like:

"When MODIS data becomes unavailable, VIIRS offers a viable alternative, but the algorithm may need adjustments to accommodate sensor differences."

[pinkychow1010]

Thank you for your response. I will do so.