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Messages - Alok Pandey

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31
Scientific community rejecting new ideas/research is not new thing. It has happened numerous times in past and may happen in future as well. But the beauty of science is that it speaks for itself, loud and clear.

So enjoy reading the below link. :)
https://www.authorea.com/users/8850/articles/117724/_show_article

32
Below is the situation climate scientists may find themselves in while recommending policies based on climate change.
We can learn a lot from this situation.
-- H. Sterling Burnett

Below are the links to the video :

Dr. Judith Curry 's  testimony: https://www.youtube.com/watch?v=GujLcfdovE8
Judith Curry on NOAA's upward 'adjustments' of temp data : https://www.youtube.com/watch?v=1UzrmaBqP3k
More Arguments during discussion : https://www.youtube.com/watch?v=Oh6zDbWMuP0

Complete Video and Main Source for the post  : https://www.youtube.com/watch?v=7QmnaMWg0M4

Comments and Observations on the above topic will be highly appreciated.

34
Answer is Bayesian Statistical Inference

Keypoints :
Statistics of groups : A basic result in statistics is that there is big difference between properties of a typical "individual" and the properties of an individual in a "typical group".

For more information watch this video : https://www.youtube.com/watch?v=KRGca_Ya6OM by MinutePhysics


35
Keypoints:
"The sea ice surrounding Antarctica has been slowly increasing in area since the satellite record began in 1979. But the rate of increase rose nearly five fold between 2000 and 2014, following the Interdecadal Pacific Oscillation (IPO) transition to a negative phase in 1999."
"To test if these IPO-related impacts were sufficient to cause the growth in sea ice extent observed between 2000 and 2014, the scientists first examined 262 climate simulations created by different modeling groups from around the world. When all of those simulations are averaged, the natural variability cancels itself out."


Link to news : http://www2.ucar.edu/atmosnews/121622/expanding-antarctic-sea-ice-linked-natural-variability

Article :
Gerald A. Meehl, Julie M. Arblaster, Cecilia M. Bitz, Christine T. Y. Chung, and Haiyan Teng. Antarctic sea-ice expansion between 2000 and 2014 driven by tropical Pacific decadal climate variability. Nature Geoscience, DOI: 10.1038/NGEO2751

37
Data / Re: Free GIS data
« on: June 20, 2016, 11:28:17 PM »
Thank you Sat,
Very Informative indeed.

38
Technique :
The ancient West African method of adding charcoal and kitchen waste to highly weathered, nutrient poor tropical soils can transform the land into enduringly fertile, carbon-rich black soils.
This indigenous sustainable soil management system in West Africa can transform infertile and carbon-poor, humid tropical soils into long-lasting, fertile, carbon-rich, and productive soils capable of supporting intensive farming in an ecologically and socially sustainable manner.

Abstract of the publication:


Reference:
Link to publication :
http://onlinelibrary.wiley.com/doi/10.1002/fee.1226/full

39
Announcements / Climate Forecast System for India
« on: June 14, 2016, 11:22:24 AM »
India's meteorology office is making $60 million Supercomputer to improve the accuracy of weather forecasts in time for next year's (2017) rains. Supercomputer will be used to run Climate Forecast System (CFS) tweaked for India, to generate 3-D models to help predict how the monsoon is likely to develop.

"If everything goes well, by 2017 we'll make this dynamical model operational by replacing the statistical model," said M. Rajeevan, the top scientist in the ministry of earth sciences, which oversees the weather office on a 30-acre campus in the heart of New Delhi.


Source of the information & attached figure: http://in.reuters.com/article/india-monsoon-forecasting-idINKCN0YT2RQ


40
Programming / Import or Export a Sequence of Files in MATLAB
« on: June 03, 2016, 12:38:43 PM »
To import or export multiple files, create a control loop to process one file at a time. When constructing the loop:

1)    To build sequential file names, use sprintf.
sprintf :
str = sprintf(formatSpec,A1,...,An) formats the data in arrays A1,...,An according to formatSpec in column order, and returns the results to character vector str.
2)    To find files that match a pattern, use dir.
dir :
dir name lists files and folders that match the string name. When name is a folder, dir lists the contents of the folder. Specify name using absolute or relative path names.


To read files named file1.txt through file20.txt with importdata:

numfiles = 20;
mydata = cell(1, numfiles);

for k = 1:numfiles
  myfilename = sprintf('file%d.txt', k);
  mydata{k} = importdata(myfilename);
end

To read all files that match *.jpg with imread:

jpegFiles = dir('*.jpg');

numfiles = length(jpegFiles);
mydata = cell(1, numfiles);

for k = 1:numfiles
  mydata{k} = imread(jpegFiles(k).name);
end

Source of information : http://in.mathworks.com/help/matlab/import_export/process-a-sequence-of-files.html

41
India Meteorology Division (IMD) has issued its second long range Monsoon forecast on June 2, 2016. The weather agency issues two long range forecasts for the Southwest Monsoon season which begins in June and lasts until September. The first forecast was already issued on April 12, 2016.

Key Points :
1. June-Sept Southwest India rainfall (ISMR) seen 104% of long period average (The LPA of the seasonal rainfall over the country as a whole for the period 1951-2000 is 89 cm). 0% probability of below normal monsoon rains this year.
2. Dynamic model forecast (CFS) estimates rainfall may be 112(+- 5)% of normal.
3.IMD Press Release : http://www.imd.gov.in/pages/press_release_view.php?ff=20160602_pr_30
Skymet Highlight : http://www.skymetweather.com/content/weather-news-and-analysis/highlights-of-imds-second-long-range-monsoon-2016-forecast/

42
Ice Melt, Sea Level Rise and Superstorms: The Threat of Irreparable Harm Blog by James Hansen, Director of the Climate Science, Awareness and Solutions program at Columbia University Earth Institute.

Video Blog : https://www.youtube.com/watch?v=JP-cRqCQRc8
Read the full transcript of video blog : http://csas.ei.columbia.edu/2016/03/22/ice-melt-sea-level-rise-and-superstorms-the-threat-of-irreparable-harm/

Some key points made in blog :


Article Information :
Hansen, J., M. Sato, P. Hearty, R. Ruedy, M. Kelley, V. Masson-Delmotte, G. Russell, G. Tselioudis, J. Cao, E. Rignot, I. Velicogna, E. Kandiano, K. von Schuckmann, P. Kharecha, A.N. LeGrande, M. Bauer, and K.-W. Lo, 2016:.. Atmos. Chem. Phys., in press.



43
Programming / Re: Regriding of Climate Data
« on: May 05, 2016, 06:35:22 PM »
The following command is used to perform regriding.

ncl interpolate.ncl

The interpolate.ncl is attached for bringing familiarity to other researchers. Also the code is pasted below:

;*************************************************
; regrid_1.ncl
;
; Concepts illustrated:
;   - Interpolating from one grid to another using bilinear interpolation
;   - Drawing color-filled contours over a cylindrical equidistant map
;   - Paneling two plots vertically on a page
;   - Adding a common labelbar to paneled plots
;   - Adding units attributes to lat/lon arrays
;   - Turning off the individual contour labelbar
;   - Manually creating lat/lon coordinate arrays
;
;************************************************
load "/usr/share/ncarg/nclscripts/csm/gsn_code.ncl"
load "/usr/share/ncarg/nclscripts/csm/gsn_csm.ncl"
load "/usr/share/ncarg/nclscripts/csm/contributed.ncl" 
;load "/usr/share/ncarg/nclscripts/csm/shea_util.ncl" 
;************************************************


begin
;=========================================;
; open original grid
;=========================================;

in = addfile("filename.nc","r")
temp = in->varname(:,0,:,:)
new_var = new((/280,72,144/),float)
do i = 0,279
  orig = in->varname(i,0,:,:)
;=========================================;
; interpolate to new grid
;=========================================;
  new_var(i,:,:)  = g2gsh_Wrap(orig,(/72,144/),0)
end do

system("/bin/rm -f interp_filename.nc") ;
b = addfile ("interp_filename.nc", "c")

       copy_VarAtts(temp, new_var)
       copy_VarCoords(temp,new_var)
       new_var@long_name = "Variablename"
       new_var@description = variable@long_name
       printVarSummary(variable)
       printVarSummary(new_var)
;       b->XLAT = xlat
;       b->XLONG= xlong
       b->varname = new_var

end
;*************************************************************


Note : command runs on linux platform.
varname : variable name as in netcdf file
filename : netcdf filename
interp_filename : interpolated netcdf filename (userdefined)
g2gsh_Wrap : One of the many ways to perform interpolation.

44
Programming / Regriding of Climate Data
« on: May 05, 2016, 06:03:09 PM »
There are various ways to perform regriding. Using NCL is one of them. Short description as follows:

NCL Overview:
The NCAR Command Language (NCL), a product of the Computational & Information Systems Laboratory at the National Center for Atmospheric Research (NCAR) and sponsored by the National Science Foundation, is a free interpreted language designed specifically for scientific data processing and visualization.

The software comes with useful command line tools:
ncl_filedump - prints the contents of supported files (netCDF, HDF4/5, GRIB1, GRIB2, HDF-EOS2/5, and shapefile, and CCM History Tape)
ncl_convert2nc - converts one or more GRIB1, GRIB2, HDF4/5, HDF-EOS2/5, or shapefile files to netCDF formatted files.
WRAPIT - allows you to wrap Fortran 77/90 routines and call them from ncl.

NCL and NCAR Graphics run on UNIX-based operating systems, including Linux, MacOSX, and Cygwin/X running on Windows.


Source : https://www.ncl.ucar.edu/overview.shtml

Regriding :
There are numerous regridding functions available in NCL. In NCL version 6.1.0, there will be new regridding capabilities available via the use of software from the Earth System Modeling Framework (ESMF). This new software will do regridding on rectilinear, curvilinear, and unstructured grids, using bilinear, patch, or conservative interpolation.
More info on https://www.ncl.ucar.edu/Applications/regrid.shtml


45
Data / Re: ABout the "Quantile map bias correction"
« on: May 03, 2016, 08:35:52 AM »
I am using R-package 'qmap' for bias correction and while using it I encountered error message for some data series as following.

 "Quantile mapping for Grid46 failed NA's produced."

Here grid 46 is 46th column of climate data (not much of issue).

Can anyone please explain the reason behind error message?

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