PlaPET

https://github.com/shoumoji/huit-space-apps-sapporo

https://www.canva.com/design/DAFGODMrRQs/UZ6-u5CXxTdb1J3JD3Kh9Q/view?utm_content=DAFGODMrRQs&utm_campaign=designshare&utm_medium=link&utm_source=publishsharelink

We believed that a proper analysis of Earth observation data could indicate how much of the limited water resources each location possesses. It is generally known that the amount of water available for human use on Earth is limited. The limited resources are not uniformly distributed on the earth. Still, they are unevenly distributed in various places, and we thought that making these limited resources accessible to more people would be a problem that should be solved both as a hackathon issue and as a social issue, and would be an initiative with great value. 

Therefore, we decided to derive an algorithm from optimizing the distribution plan of water resources. The algorithm derivation method is described below.

The water distribution problem is attributed to the Minimum cost flow problem, and the exact solution is obtained by the shortest path iteration method. First, from the viewpoint of minimizing cost, it is not optimal to distribute water so that a point with insufficient water before distribution has excess water after issuance. Therefore, this problem can be rephrased as a problem of distributing a negative amount of water to a point with a positive amount of water. If we construct the complete graph by considering the points with a negative amount of water as starting points and the issues with positive amounts of water as vertices with capacity, the problem can be further described as a "multiple starting points" and "vertex capacity constrained" minimum cost flow problem. Minimum cost flow problem" with "multiple starting points" and "vertex capacity constraints". The multiple starting points can be combined into one, and the vertex capacity constraint can be solved in the same way as the usual minimum cost flow problem by dividing the vertex into two, and thus the problem can be attributed to the minimum cost flow problem.

(More information will be provided in the README of the public repository.)

We are considering including additional functionality to the tool "panoply" in the form of a visualization of the distribution plan. Please check back for the status of the ongoing development.

https://search.earthdata.nasa.gov/search/granules?p=C1690022314-GES_DISC!C1690022314-GES_DISC&pg%5B1%5D%5Bv%5D=t&pg%5B1%5D%5Bgsk%5D=-start_date&pg%5B1%5D%5Bm%5D=download&q=GLDAS%20Catchment%20Land%20Surface%20Model%20L4%20monthly&tl=1664684422!3!!&long=0.0703125

By using "SoilMoist_S_inst" in this data, the amount of water near the ground surface at any given latitude and longitude was obtained, and from this data, water should be transported from any point to any other point every month was calculated.

In a short, intensive hackathon, setting up a problem that is both a technical challenge and a social issue was extremely challenging, and the implementation process was complicated.

As a team, we have not been able to complete the product to a satisfactory level.

The following are some of the things we would like to continue working on in the future.

We would like to calculate more accurate water resource holdings by combining multiple data sets. During the current development period, the amount of water storage was estimated from Soil moisture at a certain point. Analyzing longer-term data will improve accuracy by offsetting temporary increases or decreases in water storage.

We would like to calculate more accurate demand for how much water resources are needed. This redistribution of water resources is intended to eliminate inequalities in resource distribution. In essence, this product will achieve an equal distribution of water resources to each location. However, the question of how much demand for water resources exists in each location has not been considered at this point and requires deeper discussion to improve its functionality. Specifically, we plan to conduct additional analysis of data published in NASA's Giovanni database, which was not accessible during this development period due to a server outage.

The algorithm for calculating limited resource distribution plans is also expected to be used in planetary migration. The calculation of appropriate distribution routes for limited resources (e.g., water and oxygen) that are essential to humans and ubiquitous on planets will apply to planning activities not only on Earth but also on Mars and other planets.

- https://gracefo.jpl.nasa.gov/science/water-storage/

- https://gracefo.jpl.nasa.gov/resources/73/for-15-years-grace-tracked-freshwater-movements-around-the-world/

- https://www.eorc.jaxa.jp/en/earth_observation_priority_research/water/

#water #resources #redistribution #algorithm