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The Top 10 Forms of Complexity in Earth Surface Systems

Submitted by jdp on Mon, 01/11/2016 - 11:36 am

When we (scientists) talk and write about complexity in recent years, the focus is on complex nonlinear dynamics, and related phenomena such as deterministic chaos, dynamical instability, some forms of self-organization, fractal geometry, etc.  These are forms or sources of complexity that are intrinsic to the structure of dynamical systems, but these are hardly the only things that make systems complex. So, to make sure we don’t forget the elements of complexity that transcend so-called “complexity science,” I present the Top 10 Forms of Complexity in Earth Surface Systems (ESS). ESS is a blanket term that includes geomorphic systems, landscapes, ecosystems, soil systems, etc.  Even though the items are numbered, they are actually in no particular order. Many ESS may exhibit only a few of these forms, and still be quite complex!

The list I was gonna do has already been done ( 

Forms of Complexity in Earth Surface Systems

Reducing Reductionism

Submitted by jdp on Tue, 01/05/2016 - 08:26 am

In many of my writings I advocate an alternative to reductionist approaches to science. By alternative, I mean a complementary, different way of doing things, not a replacement for reductionism. Many excellent reviews of scientific approaches, viewpoints, and methodological stances exist by historians, philosophers and sociologists of science, and by scientists themselves. I do not intend to review or critique these various approaches here. Further, I have no intent to deny the value or necessity of reductionist science. The crux of my argument is that a reductionist approach, by itself, is inadequate or incomplete for understanding Earth.

The American Heritage Dictionary defines reductionism as an attempt or tendency to explain a complex set of facts, entities, phenomena, or structures by another, simpler set, and provides a quote from John Holland:

For the last 400 years science has advanced by reductionism ... The idea is that you could understand the world, all of nature, by examining smaller and smaller pieces of it. When assembled, the small pieces would explain the whole.

Some Observations on Observation

Submitted by jdp on Mon, 01/04/2016 - 05:37 pm

The characteristics of a place or system can be factors that are measurable or observable, or those that are not observed or observable. Of the observable phenomena, there are (at least) two different classes. First, there are those whose detection and interpretation does not vary among observers (allowing, of course, for the fact that among us there are humans exceptional in various ways). But the vast majority of humans beyond infancy will recognize, say, a rock, and will not be inclined to argue about whether or not the boulder in question is a rock or not. Suitably trained observers (e.g., geologists) may further agree that the rock is, say, granite.

‘Twas the Night Before Christmas Safety:

Submitted by jlyoun3 on Thu, 12/17/2015 - 09:49 am

Answers to ‘Twas the Night Before Christmas Safety photo:


1.      Unattended fire – never leave a fire unattended

2.      Stockings near the fire – keep combustible material away from fires

3.      Sharp hooks – don’t use sharp items to decorate if small children will be near them or attracted to them

4.      Missing fireplace screen – no grate or screen to shield from ashes, embers, and heat

5.      Dry Christmas tree – dry trees are fire hazards

6.      Broken lights – malfunctioning lights pose a fire and electrical hazard

7.      Obstructed doorway – large items (rocking horse) is blocking a fire escape pathway

8.      Frayed cord – electrical hazard (note: no more than 3 strands of standard size lights on each surge protector)

9.      Toxic snow – artificial snow is toxic and should not be left out in the reach of small children or pets

10.  Unextinguished lights – Christmas lights left on extended periods of time

Tech Tips from the Hive

Submitted by smbrad3 on Tue, 12/15/2015 - 10:38 pm

Have you ever received a new work computer, bought a new computer for home, or had a hard drive fail and wondered how you would migrate all of your browser settings (Chrome, Firefox) to the new computer?  Both Google Chrome Sync and Firefox Sync allow you to bring your bookmarks, saved passwords and other browser settings to any computer you use.  Both features require you to sign in to the application, but once signed in you can then enable sync to any device you use.  We’ve created Tutorials to help you with the process.  Click here for the Firefox Sync Tutorial, or click here for the Google Sync Tutorial.

Need to access your office computer and work files from home?  Install the UK Cisco VPN client and use Remote Desktop to access your work whenever you’d like without coming in to the office.  The Hive has created tutorials to walk you through the process of downloading and installing the VPN client, and accessing your work machine using Remote Desktop.  Have a look at these tutorials to get started:

Brad's Blurb

Submitted by bdharr3 on Tue, 12/15/2015 - 10:36 am

Hello A&S Staff and Friends,

With winter weather just around the corner, I wanted to pass on the HR policies related to severe weather delays/closures at   In general, UK's policy is to keep all offices open and classes meeting as scheduled except under extraordinary weather conditions.  The most accurate and complete information on cancellation of classes and closure of offices can be found on the UK main website at   The University's concerns around winter weather extend beyond campus policy and procedure, to the safety of every member of our community.  With this in mind, check out the new UK WalkSafe website for safety tips at:   Last winter, there were several reported injuries related to slips/falls on campus sidewalks.  It can take some time for the UK ground crews to remove the snow and ice from walkways, so it is important to be aware of sidewalk conditions when arriving and departing work.

The Principle of Gradient Selection

Submitted by jdp on Tue, 12/08/2015 - 05:45 pm

Flows of mass and energy occur along the steepest gradients of potentials or concentrations.  The principle of gradient selection is simply that features associated with these gradients persist and grow. Take, for instance, the redistribution of excess (i.e., more than the ground can absorb or retain) surface water. Hydraulic selection principles favor the most efficient paths, which we can generally interpret as the fastest pathways. Thus the steepest slopes and/or the routes with the lowest resistance to flow attract more water. The most efficient paths persist and prevail; less efficient options dry up.  For example:

Standard flow resistance equations are of the general form

V = f(RaSbf-c)

where R is hydraulic radius (cross-sectional area divided by wetted perimeter; typically roughly equal to mean depth), S is slope (hydraulic gradient), and f is a roughness or frictional resistance factor. The exponents a, b, c < 1. For example, the D’Arcy Weisbach equation is

V = 8g R0.5 S0.5 f-0.5

Threshold Modulation vs. Steady-State

Submitted by jdp on Thu, 12/03/2015 - 03:13 pm

Threshold modulation

Upper and lower limits

In terms of mass balances or budgets, geomorphic systems have three fundamental states, whereby losses or removals are either greater than, less than, or roughly equal to inputs or gains (i.e., steady-state). Thus a regolith cover, for instance, is either thinning, thickening, or maintaining steady-state relative to the rates of mass losses and inputs, and weathering and regolith formation.

The principle of threshold-mediated modulation holds that thresholds limit development on both ends (negative or positive mass balance), and that exceeding the thresholds may initiate development in the opposite direction. For instance, vertical accretion on alluvial floodplains is limited by an elevation at which regular flooding no longer occurs, thus limiting further accretion. In addition, confinement of flows within the channel may increase stream power and shear stress, thus ultimately resulting in stripping of the alluvium.

The Balance of Nature, and the Nature of Balance

Submitted by jdp on Wed, 12/02/2015 - 08:58 am

If Mother Nature has plans, those plans are flexible. She keeps her options open, allows for more than one route to a given location, and we cannot assume that the same circumstances will always produce the same outcome. To digress for a moment: accepting this need not challenge religious or philosophical beliefs about a creator. Nothing in the bible, for instance, specifies exactly how the Judeo-Christian God goes about his/her business, or specifies any single pathways or mechanisms. As a protestant minister I knew well used to say: “Religion is concerned with the ‘why’ questions, and science addresses the ‘how.’”

Indeed. 35 years in the geoscience research business has shown me that that there is no single “right” or “natural” way for the world to be. Any human notions of singular, immanent norms or optima are tied to needs, goals, or perceptions, not scientific laws or relationships. And—again—there is nothing wrong with having such goals, desires, or expectations for nature, any more than there is anything wrong with a farm or a garden. The key is to realize that there is not much point in expecting Earth surface systems to evolve toward and maintain a single specific condition, any more than we would expect a garden to maintain itself without some guidance and intervention.