Cell Phone Towers: New Age Rainfall Gauge
Cellular phones or Mobile phones have become indispensable in todays age and society. SMS and Mobile Internet made them tools of social networking and information sharing.
Cell phones went scientific with Smart phones becoming sensors for crowd sourcing of environmental data.
Now Imagine Cell phone towers acting as rainfall gauges! A team of researchers from the Royal Netherlands Meteorological Institute and Wageningen University, Netherlands have published a paper – ” Country-wide rainfall maps from cellular communication networks” on using cell phone signals to build rainfall maps.
We all know that Network operators use microwaves to link cellular towers & mobile phones together. When it rains, the signal received at the next tower down the line are weakened by reflection off raindrops. A phenomenon that is referred to as rainfall induced attenuation.
How is this going to help?
The answer lies in the abstract of the paper. From the abstract “Accurate and timely surface precipitation measurements are crucial for water resources management, agriculture, weather prediction, climate research, as well as ground validation of satellite-based precipitation estimates. However, the majority of the land surface of the earth lacks such data, and in many parts of the world the density of surface precipitation gauging networks is even rapidly declining.”
The technique is to record the signal strength of microwave transmissions of each cellular tower from the neighboring tower. Since the distance and signal strength at the transmitting tower are known, it can be easily modeled and any difference in signal strength is a pretty good indicator of attenuation.
Using data provided by T-Mobile, Aart Overeem and his team have developed an algorithm to measure the differences and predict the rainfall level.
In the paper, one can see that the team succeeded in their efforts. They mapped rainfall between June and September 2011 and found that readings derived from cell phone tower data tended to agree with those from the traditional rainfall gauges and radar.
This could really solve the power of having accurate measure of rainfall in different parts of the world. WIth decreasing number of rainfall gauges, meteorologists across the world were having issues predicting and quantifying rainfall in remote locations and locations that were in between 2 rainfall gauges. This innovative idea can help solve that issue and help measure rainfall with much better accuracy.
Cell Phone Towers are the new age rainfall gauges.
British Library’s Georeferencer project
Maps are certainly beautiful. The beauty and magnificence of maps are something all of us have witnessed in the past. If you dont agree with me, then take a look at british library’s treasure trove! By now, I bet you are just as fascinated by maps as I am.
All said, somehow I feel the beauty of maps lies with the old maps. The maps of the yesteryears were the best. The cartography was amazing. Hold that thought right there!
Imagine having a API that lets you view old maps of your city and overlay them on top of the latest satellite imagery. Imagine being able to see ancient/historic and modern maps at the same time. Imagine being able to see something like a Map timeline using a slider. A wonderful wish indeed!
Now that where British Library needs your help. Its in the process of turning all those wonderful ancient maps it has into a digital treasure trove.
For our wonderful dream to come true, British library is seeking people to help Georeference the old maps. Its quite simple: we find locations that can be considered as control points and georeference them.
At the end of it all, its easy for us to slide through centuries and view the city when it was young. Marvel at the accuracy of cartographers who didnt have GPS, Total Stations and other modern surveying equipment to prepare these maps.
We can visualize the errors, upload it to Google Earth and a lot of other cool stuff as well.
So what are you waiting for, go georeferencing then for British Library!
P.S: British Library even has the statistics of people who helped them the most – have a look.