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I've just had a mini "Eureka" moment that I wanted to share.<br>
<br>
As I've been processing more weather data from the ISD, I've been
countering more cases for smaller locations (mostly in the US) where
there are two weather stations where the WMO numbers are the same
for the first part but not for the smaller part. For example, for
Socorro New Mexico there are two files:<br>
<br>
2014 NM_SOCORRO-MUNI-AP 723620 93040 <br>
2014 NM_SOCORRO-MUNI 723620 99999 <br>
<br>
I generally interpret these cases as where a station may be
switching their instrumentation. However, in this case the two
stations seem to be reporting at alternating times (table below
shows the number of observations by month for the 4 key climate
parameters that I need):<br>
<br>
NM_SOCORRO-MUNI-AP 723620 34.067 -106.900 1485 4
-7.0 NAM BSk<br>
2014 dbt 464 302 151 538 697 155 0* 0* 511 710 244
0* 419<br>
2014 dpt 462 297 148 535 696 154 0* 0* 505 710 244
0* 416<br>
2014 cld 451 245 108* 477 646 153 0* 0* 413 652 217
0* 373<br>
2014 wsp 464 302 151 538 697 155 0* 0* 510 710 244
0* 419<br>
2014 all 1841 1146 558 2088 2736 617 0 0 1939 2782 949
0<br>
<br>
NM_SOCORRO-MUNI 723620 34.022 -106.903 1485 4
-7.0 NAM BSk<br>
2014 dbt 259 389 610 161 41* 549 689 698 224 0* 444
684 431<br>
2014 dpt 256 385 607 159 38* 545 687 698 224 0* 443
684 429<br>
2014 cld 259 312 550 144 41* 549 598 583 182 0* 435
625 388<br>
2014 wsp 259 389 610 161 41* 549 689 698 224 0* 444
683 431<br>
2014 all 1033 1475 2377 625 161 2192 2663 2677 854 0 1766
2676<br>
<br>
I have software to merge data from two files but only at defined
switchover dates, so this situation seemed at first quite hard to
tackle. <br>
Then, I thought, why not just take concatenate the two raw data
files, and then sort the combined file to get the data in the right<br>
chronological order? That took me just a few seconds, and voila' ,
out comes a full weather file with quite high data completeness:<br>
<br>
NM_SOCORRO-MUNI-AP2 723620 34.067 -106.900 1485 4
-7.0 NAM BSk<br>
2014 dbt 713 643 714 690 710 690 689 698 688 710 687
691 693<br>
2014 dpt 713 643 714 690 710 690 687 698 688 710 687
690 693<br>
2014 cld 700 531 635 613 671 688 598 583 565 652 651
625 626<br>
2014 wsp 713 643 714 690 710 690 689 698 687 710 687
690 693<br>
2014 all 2839 2460 2777 2683 2801 2758 2663 2677 2628 2782 2712
2696<br>
<br>
A quick look at the plots also showed a weather file of seemingly
good quality:<br>
<img src="cid:part1.04050904.03050408@whiteboxtechnologies.com"
alt=""><br>
<img src="cid:part2.09080606.01030102@whiteboxtechnologies.com"
alt=""><br>
<br>
Problem solved!<br>
<br>
Joe<br>
<pre class="moz-signature" cols="90">--
Joe Huang
White Box Technologies, Inc.
346 Rheem Blvd., Suite 205A
Moraga CA 94556
<a class="moz-txt-link-abbreviated" href="mailto:yjhuang@whiteboxtechnologies.com">yjhuang@whiteboxtechnologies.com</a>
<a class="moz-txt-link-freetext" href="http://weather.whiteboxtechnologies.com">http://weather.whiteboxtechnologies.com</a> for simulation-ready weather data
(o) (925)388-0265
(c) (510)928-2683
"building energy simulations at your fingertips"
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