Unintentionally profound EPA: “All cohorts are subject to mortality”

Buried deep within the technical documentation of an EPA land use model is a profound philosophical insight. It’s not merely about the environment or land use, but about life itself:

Similarly, mortality is estimated by multiplying the number of people in given cohort times the cohort-specific mortality rates. The resulting number of deaths is then subtracted from the cohort. Unlike fertility, all cohorts are subject to mortality. Therefore, mortality rates are applied to each cohort.

Alright, I suppose it may be unintentionally profound.

This quote is taken from the documentation of the Integrated Climate and Land-Use Scenarios (ICLUS) model developed by the US EPA (12 MB PDF) . Unlike the US Census Bureau’s population projects, which only have nationwide tallies, ICLUS generates detailed population density and impervious surface rasters for the contiguous USA through the year 2100. This particular section of the documentation describes how the model accounts for births (fertility) and deaths (mortality) within the population during each time step.

This adage about the impermanence of life reminds me of the similarly unintentionally profound Wii notification: “Warning: Everything saved will be lost” as discussed on Reddit in 2013.

How the human mind finds meaning in the strangest places…

Calculating Geodesic Areas in ArcMap with Field Calculator

Calculating polygon areas is one of the most basic geometric operations. Most GIS analysts using ArcGIS are taught to calculate polygon areas in ArcMap using the Calculate Geometry tool in the attribute table. This allows the calculation of area in the coordinate system of the data source or the coordinate system of the data frame in the desired areal units.

The old calculate geometry tool
The old calculate geometry tool

Although this tool fulfills most use cases, it falls short in a number of ways.

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Changes to Default ArcMap Settings

After upgrading to ArcGIS 10.3 last week, I went through the usual process of reapplying all of my settings and preferences in ArcMap. To expedite this process, a couple years ago I created a list of all of my preferences in ArcMap: toolbars, ArcMap Options, Geoprocessing Options, menu items, Environment Settings, and Advanced ArcMap Settings. At the suggestion of some of my colleagues, here’s the list in full.

1. Toolbars

By default, ArcMap shows two toolbars: Standard and Tools.

Default ArcMap toolbars
Default ArcMap toolbars

There are almost 50 other toolbars that can be added by right-clicking in the header area (or toggling in the Customize dialog).

List of ArcMap toolbars
List of ArcMap toolbars

But turning them all on at once is not a good idea. This overload of toolbars, many of which are only useful in specific contexts, is one of the reasons Microsoft moved Office to the ribbon-style UI. Esri has implemented the same ribbon in ArcGIS Pro, though I will miss some of the customization aimed at power users.

ArcMap with all toolbars turned on...yikes
ArcMap with all toolbars turned on…yikes

So for my day-to-day ArcMap work, I have the following toolbars enabled: StandardEditor, and Snapping in the first row; ToolsLayout, and Labeling in the second row; and Draw and Graphics in the third row. Organizing the toolbars in these rows allows for a comfortable fit in a window that is around 1,200 pixels wide.

My ArcMap toolbar setup
My ArcMap toolbar setup

Customize mode also allows adding or removing specific tools on specific toolbars if further tweaks are needed.

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