Subject:   How to Subdivide Subcatchments in SWMM 5

If you want to subdivide a larger Subcatchment in SWMM 5 and get around the same peak flow then a good suggestion would be to make sure that (Figure 1):

1.   The sum of the new areas equals the original Subcatchment Area and

2.   The sum of the total Width values equals the original Subcatchment Width on the one Subcatchment

3.   The infiltration, percent imperviousness, roughness and depression storage should be the same. 

Figure 1.  Subdividing a Subcatchment

Subject:   How to Subdivide Subcatchments in SWMM 5

If you want to subdivide a larger Subcatchment in SWMM 5 and get around the same peak flow then a good suggestion would be to make sure that (Figure 1):

1.   The sum of the new areas equals the original Subcatchment Area and

2.   The sum of the total Width values equals the original Subcatchment Width on the one Subcatchment

3.   The infiltration, percent imperviousness, roughness and depression storage should be the same.

Figure 1.  Subdividing a Subcatchment

How Good Were Climate Models 30 Years Ago?

July 17, 2012 

by ADAM FRANK  http://www.npr.org/blogs/13.7/

Geet Jan van Oldenborg

Models vs Reality: Gray lines are predictions from 1981 models of global temperature increase. Red line is real world data.

Pretty good it appears.
In a piece back in April at RealClimate, guest bloggers Geert Jan van Oldenborgh and Rein Haarsma of the Dutch Meterological Institute (KNMI) look at back at a 1981 paper by the now famous James Hansen and others. At the time, of course, neither Hansen or global warming were household names. Still the paper got noticed. As the Oldenborgh and Haarsma explain:
"They got 10 pages in Science, which is a lot, but in it they cover radiation balance, 1D and 3D modelling, climate sensitivity, the main feedbacks (water vapour, lapse rate, clouds, ice- and vegetation albedo); solar and volcanic forcing; the uncertainties of aerosol forcings; and ocean heat uptake."
The Hansen et al paper includes (among other things) a plot of predicted global temperatures as a function of time. Oldenborgh and Haarsem take this figure and overplot the actual real world data gathered since the paper appeared. The fit between the Hansen et al predictions and the behavior of the Earth's climate is remarkably good. This is even more remarkable when you realize your iPhone now might have comparable computing power to the machines they were running their simulations on.
The lesson to draw from all of this is obvious. The basic principles of climate science has been mature for a while. While there remain significant issues to understand such as the local response to global (human-driven) CO₂ increases, the links between greenhouse gas emissions and greenhouse driven climate change is decades old news.
Perhaps, during this crazy summer, that news is finally getting past the denier screen and reaching the general public.

Subject:   How to Easily Make a Smaller Model in InfoSWMM Using Trace Upstream Network

Step 1.  Use the Trace Upstream Network command to find all of the network above the node of interest (Figure 1). 

Step 2.  Use the Trace Downstream Network Command to find all of the network below the node of interest and place it in the Doman (Figure 2).

Step 3.  Use Facility Manager to make the Lower Network in the Domain Inactive (Figure 3).

Step 4.  Change the Node of Interest from a Manhole to an Outfall

Figure 1.  Trace Upstream Network

Figure 2.  Put the lower Section of the Network in a Domain

Figure 3.  Use Facility Manager to make the Lower Network in the Domain Inactive

Subject:  Tweet Topic Explorer for your Tweets on Twitter

Tweet topic Explorer is a good way to see your tweets visually http://tweettopicexplorer.neoformix.com as shown for the Tweet Topic Explorer View for my Twitter Address rdickinson using the Tweet topic Innovyze.