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Our pixel for our people

Posted by F on

As Michel Verstraete said,  “If you have control of your own satellites, you don’t have to ask your friends or your enemies” .We need to prepare our owned satellite or if we have only small capital, we can make our own small-vehicle-sensor or UAV. Addedd with thermal infrared sensor to enable monitor the water utilize, top soil and land surface temperature, plants condition, paddy field, and water consumption in agricultural fields, and others.

We need to keep our intention in the continuity of agricultural and vegetation monitoring in the age of increasing population. Regarding this issues, Landsat 4 to Landsat 7 ETM+ had provided us with high valuable remotely-sensed images for neary 30 years. However now Landsat optical sensor face the problems with SLC-Off. With 7 billion of world population, the continuity of earth monitoring have been prepared by NASA for lauch Landsat 8 or Landsat Data Continuity Mission (LDCM). It is scheduled for launch by NASA earlier than January 2013.

The sensor will have 12 band and according to NASA: “The centerpiece of the LDCM space segment is the OLI (Operational Land Imager). By collecting land-surface data with spatial resolution and spectral band specifications consistent with historical Landsat data, the OLI instrument will advance future measurement capabilities. The OLI will feature two additional spectral channels: a “ultra-blue” band for coastal and aerosol studies, and a band for cirrus cloud detection. A thermal infrared sensor (TIRS) will collect data in two long wavelength bands that will be co-registered with OLI data.”

Can you find something in the above statements from NASA? Yes, the spatial resolution is still same with the previous Landsat 7,to keep the continuity of earth monitoring. I think it is good to keep this spatial resolution of multispectral band, but increase the panchromatic band to 10 meters at least is better.Continuity is important but competitiveness with the latest commercial platforms is also important. With the wide swath of Landsat, it will make us have better understanding in regional analysis than in small scale study area, with lower cost surely.

Back to our first concern, have control of our own sensor is the best things ever! With the low cost, easy operation, high spatial resolution, high accuracy, and can give more benefit for poor people such as farmer in agricultural fields in Indonesia. We do not have to buy from “our enemy”, we can provide our peoples with good images for monitor and control their environments for their own good. We can run it continuity and give it free for everyone! we can monitor deforestation from illegal expansion of plantation and forest industry, impact to local climate, changes in cropping systems and irrigation practices and give better solution, predicting drought earlier and prevent from starving disaster , conversion of land from its natural stated, and managed and control the urban growth.

We need to prepare our own small-vehicle-sensor to feed our peoples, increase their prosperity, welfare, their joy of life. and UAV is the best choice I think. Indonesian’s remote sensing scientist need to focus to this area than focus on satellite orbiting the earth. We need to much money to launch the satellite, and our political condition will not support us for this reason.  Building a satellite is not an easy work, we need collaboration and involves the hard work of many different types of scientist and engineers. The process involves defining the satellite requirements, testing the design, building the instruments and satellite, testing the instruments and satellite, integrating the satellite and instruments together, launching the satellite, and then operating the satellite once it reaches its orbit. Too much work for the  fast development, increasing population, and dramatically changing of our nation.

In the future I have plan to build Geo-science Institute, but this institute is not for who wants to get academic title, degree, or diploma, but for everyone who wants to be enterpreuneur and build the welfare country, we need to be free from capitalist!

Comparing near-natural colour composite to LST (Land Surface Temperature) using GRASS

Posted by F on

Next stage is comparing your land surface temperature map with near-natural colour composite using GRASS. We can do this by type this formula into command console:

Create (only for display) near-natural colour composite of Landsat7 ETM+

d.rgb red=L71107033_03320120314_B30@PERMANENT green=L71107033_03320120314_B20@PERMANENT blue=L71107033_03320120314_B10@PERMANENT

Now we can see white colour is for snow cover, green for vegetation, and clear characteristics for urban environment.

Start new map display, and then open your temp_celcius@PERMANENT, and then compare your images. Now we see clearly, the urban areas has higher surface temperatures than the other environment, such as mountain range and river networks.

You can also make RGB composite using different formula, this formula is to create file and save into your  working directory:

r.composite red=L71107033_03320120314_B30@PERMANENT green=L71107033_03320120314_B20@PERMANENT blue=L71107033_03320120314_B10@PERMANENT output=n-ncolor

Image

Application of satellite-derived surface temperature analysis

Posted by F on

As in my previous post, I’ve been showed you how to derived surface temperature using band62 (high gain) of Landsat7 ETM+, in this post I would like to let you know the application of satellite-derived surface temperature.

In geographical analysis we believe there are no one place on the earth with the exactly similar characteristics! So, one approach to understanding the dynamic-change earth is analyse the surface temperature. There are so many application of satellite-derived surface temperature in Remote sensing, below is some case I list for you:

1. Urban heat island, one of the most famous application is “the hot points” of the urban settings, and related to the urban surface characteristics and land use type.

2. Vegetation stress in agriculture, we can analyse and predict the harvest condition (gross primary production of some plants)

3. Vegetation parameter to understanding and predicting the run-off and soil erosion

4. Regional water stress and drought assessment

5. Identification of volcanic activity

6. Habitat classification, suitability, and changed trend in ecosystem analysis

7. Earthquake that induced thermal anomalies, however this is still premature study, we need more research for this application, you can find full article here

All application I mentioned above are applications of satellite-derived surface temperature in land, not on water/sea surface

 

How to derive surface temperature from thermal band using GRASS?

Posted by F on

GRASS is open source software, you can manage your imagery using this kind of software. Especially for anyone who has interest on imagery processing, using GRASS Raster map calculator is very convenient. You can download GRASS from this link .

Basically, to derive surface temperature we need to prepare our thermal band imagery, in this case we will use band62 (high gain) from Landsat ETM+ of Sendai, Miyagi Prefecture, JAPAN. Date acquisition is March 14, 2012.

Before begin, we need to make sure that atmospheric correction of the image is already taken for absolute calibration of satellite-derived surface temperature. Please refer to _MTL.txt for atmospheric correction variables needed.

OK, now lets start with (1) calculate the spectral radiance (convert DN to spectral radiance) at the image, the formula is:

L= ((LMAX − LMIN)/(QCALMAX − QCALMIN))(QCAL − QCALMIN) + LMIN

(GSFC/ NASA, 2001)

in command console GRASS you can input this formula:

r.mapcalc band62=((12.65-3.2)/(255-1))*(L72107033_03320120314_B62@PERMANENT-1)+3.2

from _MTL.txt we can find this variables:

QCALMAX_BAND62 = 255.0
QCALMIN_BAND62 = 1.0
LMAX_BAND62 = 12.650
LMIN_BAND62 = 3.200

“band62″ is name for output result

“L72107033_03320120314_B62@PERMANENT” is location of band62 in your working directory. When the first time you launch GRASS, you will ask to defined your working directory!

Next step is (2) convert spectral radiance into kelvin, type this formula is command console:

r.mapcalc temp_kelvin=1282.71 / log(666.09 / band62 + 1)

and to (3) convert kelvin to degree celcius you can type this formula:

r.mapcalc temp_celcius=temp_kelvin – 273.15

r.info -r temp_celcius

r.univar temp_celcius

the result output will inform you the min temperature, max temperature, range, mean, standard deviation, etc.

To apply new colour table you can use this formula:

r.colors temp_celcius col=bgyr

GRASS Window

Nano remote sensing: small vehicle-nano sensor

Posted by F on

Its glad to know the development of new technology in this information booming era. When many government and company compete each other with new development of satellite and sensor with new constellation and in big size, now we are served with the development of small vehicle research and nano technology.

In the field of remote sensing, it seem in the future the use of small vehicle equipped with nano-sensor will become new actor on earth-environmental monitoring. From this video on youtube, we can see how is the development of small -even very small if we compared with satellite- vehicle is incredible! According to the explanation of the up-loader the “experiments performed with a team of nano quadrotors at the GRASP Lab, University of Pennsylvania. Vehicles developed by KMel Robotics.”

I am wondering how if this technology used in the monitoring inside the mining hole, to understanding the geological structure more details. Or how if we used this kind of small vehicle in remote wetland area to explore more details about the vulnerable environment. Or to monitor the flower agriculture in large area, to know it’s healthy or not

Next stage I think is the development of nano-sensor to be added on the small-vehicle. With the availability of nano technology it seem not to difficult to build new nano-sensor that can attached on.

Small-vehicle

‎7 things, the future of GIS: Now happening

Posted by F on

As I wrote in my another homepage (click here for details) about the future of GIS, one of the future thing is now happening. For a simple case is written here, where peoples without any basic theory or understanding about Geographical Information System can do GIS without any cost, totally free!

Article above gave us a sample map about what was happened in England’s riots, when poverty was has correlation with. You can access the map from this link

Correlation between poverty and riot in London, England

However, if we want to make Indonesian people more concern about their environment or how to make their government work for them, it is little bit difficult because lack of internet access and information/spatial data unavailable.

Now, I am working to compile all my satellite image, coverage whole over Indonesia, and in the future I would like make it available and easy to access. And make people understand about their environment, understand the consequences, consider to make action, and force the government work for them!

A gift from Tohoku’s earthquake (March 11, 2011)

Posted by F on

From a routine GCOE seminar, which is held in the campus regularly, there is an interesting research. Author, title, and quote of his paper are written below:

Author: Senior Fellow Shuichi Kodaira

Title: “Geophysical evidences of co-seismic fault breaking at the trench axis by the 2011 Tohoku-oki earthquake”

Quote: “From bathymetry and seismic surveys along existing profiles immediately after the earthquake and compared the data acquired before and after the 2011 earthquake. From this analysis, we detected considerable bathymetric deviation at the landward side of the trench, extending up to the trench axis and estimated that the seafloor on the landward side of the trench moved 50 m horizontally in the SE to ESE direction, and 10 m upward. This observation suggests that the plate coupled zone between earthquakes may extend at the shallowest part of the subduction zone, which is used to believe to be a stable sliding region.”

So, after last year big earthquake, has caused Japan’s trench to shifted horizontally as far as 50 m and lifted 10 m vertically. Zone meeting of the plate between each occurrence of the earthquake would extending the shallowest part of subduction zone, which is believed will make the Tohoku region shifted in a more stablestate. Or in other words in the near future Tohoku region is relatively safe from deadly major earthquakes.

Map below help us to understand the spatio-situation of Tohoku region in Japan after hit by big earthquake last year. (picture from: Shestakov, Nikolay V., Takahashi, Hiroaki, Ohzono, Mako,Prytkov, Alexander S., Bykov, Victor G., Gerasimenko, Mikhail D., Luneva, Margarita N., Gerasimov, Grigory N., Kolomiets, Andrey G., Bormotov, Vladimir A., Vasilenko, Nikolay F., Baek, Jeongho, Park, Pil-Ho, Serov, Mikhail A., Analysis of the far-field crustal displacements caused by the 2011 Great Tohoku earthquake inferred from continuous GPS observations, Tectonophysics (2011), doi: 10.1016/j.tecto.2011.12.019)

Comparison of the observed (black arrows) and computed (white arrows) horizontal coseismic displacements at the GEONET sites.

Expansion of remote sensing research

Posted by F on

Nowadays, technology continues to grow, even beyond the estimates that have been previously calculated, including remote sensing technology.

Expansion beyond the scope of remote sensing technolgy that I think before, I thought that this technology is to monitor the earth’s surface and the content in the earth, but now includes the building of man-made constructions (http://www.slideshare.net/giorgiobarsacchi/ibisl-ibisl-an-innovative-solution-for-remote-monitoring-of-displacements-on-slopes-and-structures), previously, I only use it to see the pattern of land use land cover change only, but now it is able to predict future land use with high precision, resources management and habitat assessment (http://www.clarklabs.org/products/Land-Change -Modeling-IDRISI.cfm), monitor climate change and to model future trends (http://clarklabs.org/about/Clark-Labs-Unveils-IDRISI-Selva.cfm), and even calculating the volume change of the earth and earthquake prediction by only using UAVs (http://www2.cr.chiba-u.jp/mrsl/coestartup.html)

As a simple conclusion, it may be said that the movement of world changes more quickly and dynamically, and technology continues to adapt for a better earth managements. And the most important thing we should do as a researcher in the future are (if we choose to making career outside Indonesia, but still want to contribute to developing Indonesia): 1. internship program to up-grade the skills of domestic young scientist in our institution; 2. establishment of representative office in Indonesia to get smart at young scientists; 3. popularize appropriate technologies to increase community involvement in sustainable earth management; 4. If you decide to back home, please consider to be a political leader such as Governor or even President!