My WebLink
|
Help
|
About
|
Sign Out
Home
Browse
Search
WMOD00279
CWCB
>
Weather Modification
>
Backfile
>
WMOD00279
Metadata
Thumbnails
Annotations
Entry Properties
Last modified
7/28/2009 2:29:19 PM
Creation date
7/18/2007 2:18:33 PM
Metadata
Fields
Template:
Weather Modification
Title
Applied Weather Associates Responses to Corps of Engineers Questions on the AWS Study of Cherry Creek PMP, Sept 2006
Prepared For
USACE
Prepared By
Applied Weather Associates
Date
1/29/2007
County
Douglas
Weather Modification - Doc Type
General Information
There are no annotations on this page.
Document management portal powered by Laserfiche WebLink 9 © 1998-2015
Laserfiche.
All rights reserved.
/
23
PDF
Print
Pages to print
Enter page numbers and/or page ranges separated by commas. For example, 1,3,5-12.
After downloading, print the document using a PDF reader (e.g. Adobe Reader).
Show annotations
View images
View plain text
<br />Ci ,,'Jip. <br /> <br />Weare trying to look into the details of this question, A couple of issues are impacting our <br />efforts... ,1) we have changed GIS guys and 2) we have upgraded our GIS software. However, <br />we do have the archived images and are trying to quantify the answer to this question. <br /> <br />Having said that, what appears to have happened is that one of the trial placements for the Falcon <br />1965 isohyetal pattern (see A W A response to Question 8.) was included in the March 2003 <br />version of the report instead ofthe final placement ofthe isohyetal pattern that is included in the <br />Final Report August 2003. An indication ofthat is the fact that the August 2003 pattern on page <br />69 of the Final Report has the Basin Average Rainfall included in the figure where the March <br />2003 version does not. Since the table of average rainfall depths from the two reports agree (as <br />the COE noted), it appears that the Figure 4,13 was the one actually used in both versions of the <br />report and the figure in the March 2003 is not correct figure for the computed rainfall depth. <br /> <br />11. Page 71. Why was the NWS isohyetal analysis not used for the 1965 Holly storm? <br /> <br />A W A response to Questionll. <br /> <br />A W A used GIS to produce an isohyetal pattern for this storm using all available rainfall data for <br />this storm center. Comparing this GIS derived rainfall pattern with the NWS isohyetal analysis, <br />the areas of extreme rainfall were larger using the GIS isohyetal pattern. A W A elected to use the <br />GIS isohyetal pattern since it provided the most conservative (largest) rainfall amounts. <br /> <br />12. Page 74. What does "1.50(a)" mean for the In-place Maximization factor? <br /> <br />A W A response to Question 12. <br /> <br />The answer to this question is the same as the answer to Question 3, <br /> <br />A W A concurs with the NWS conclusion that there should be upper limits place on in-place <br />maximization factors. The basis for this conclusion is that the maximization procedure assumes <br />that a storm's efficiency in converting atmospheric moisture to rainfall remains unchanged <br />during the maximization process, i.e. atmospheric moisture can be added up to the maximum <br />value used in the maximization process without changing the storm efficiency. Adding moisture <br />to the atmosphere associated with a rainfall event can and does have an effect on storm <br />efficiency and at some point the assumption that additional moisture has not effect on storm <br />efficient is not valid. NWS has adopted upper limits to storm maximization. HMR 51 applied a <br />limitation of 1.50 to the maximization factor (HMR 51, Section 3.2.2, page 28). HMR 55A, <br />Section 8.4..1.1, page 131, provides some discussion on limitations to in-place maximization <br />adjustment. HMR 55A adopted the 1.50 limit for the nonorographic region east of the <br />Orographic Separation Line (OSL) (HMR 55A, Section 5.4, page 88), Both HMR 55A and the <br />newer HMR 57 apply a limitation of 1. 70 in orographic regions. This limit was adopted to allow <br />for inadequacies of the storm sample in orographic regions (HMR 55A, Section 8.4.1.1, page <br />131; HMR 57, Section 7.2, page 66). A W A used the limitation of 1.50 for Cherry Creek and <br />annotated when it was applied with "1.50(a)", indicated that the adopted value of 1.50 was used <br />instead ofthe higher calculated in-place maximization value for the storm. <br />
The URL can be used to link to this page
Your browser does not support the video tag.