Dendritic Stream Branching in the Piedmont and Triassic Basic

Who can spot Chapel Hill??

Regolith -- Silicate Mineral Weathering

All diagrams are from the excellent :

Regolith Geology and Geomorphology
G. Taylor, R. A. Eggleton, Richard A.. Eggleton
John Wiley & Sons, Aug 30, 2001

Prescribed Fire at Mason Farm

North Carolina Botanical Garden volunteer "Firebugs" conducted a controlled burn at Mason Farm last friday (March 15th) through the forest and two fields.  On Sunday an old log was still smoldering in the forest, while green grass leaves were already appearing from the charred field!

Biogenic VOC emissions

Trees and natural vegetation release air pollutants (biogenic), just like people (anthropogenic).

Figure from a great website by Dr. Wilson from Duke University, with lots of information.

The overall amount of this pollution can be modelled:

http://www.sciencedirect.com/science/article/pii/S1352231005000907

Its important to put this into perspective: human (anthropogenic) emissions of VOCs can be 40 times greater than the highest modelled biogenic emissions.  But the compounds plants produce may be more effective in generating hazardous compound Ozone.  Atmospheric chemistry is complex, and it is ironic that the highest biogenic pollution emissions occur in the same areas that high anthropogenic pollution also occurs, compounding the problem.  

Spring Bird Migration on radar!

from Cliff Mass.

Water Year

Now that it is March and the winter rains are almost finished, let's look at who got what.  The West remains in a deep drought.

 Do Highs and Lows (e.g. 500mb height anomalies) force jet stream diversions or does jet stream bunching and coiling create ridge and troughs and hence Highs and Lows?


The Weather Channel notes that February upper-level (jet stream) synoptic pattern brought very cold air to the Eastern U.S.

Looking ahead to May, they predict that the continuing drought in the Western Plains will continue and set up a feedback loop: drier surface conditions will create a bubble of high pressure air that will in turn influence the average track of the jet stream, pushing storms north of the rain-starved regions.  This is just one possibility, however, and even then only reflects average conditions.

Spittle Bugs

We have been seeing spittle bubbling out of trees, especially in today's rain.  Might be a spittlebug.

"a fat little dark-eyed green creature about the size of a sesame seed called a froghopper nymph, so named for the adult insect's squat shape, pop eyes and leaping ability. The nymph stage is better known as a spittlebug. Froghoppers/spittlebugs insert their "beak" & suck sap through their bodies, extracting nutrients. As the liquid comes out the other end, mixed with soapy abdominal secretions, the insect puffs air into it through a special organ, blowing bubbles. The froth flows down and around the nymph (they feed facing head down), keeping it cool, moist and hidden from you (unless you look)."

Maps of Puerto Rico

Bankfull Flood on the Haw River, North Carolina

There is abundant evidence of a bankfull flood event on the Haw River, upstream of Bynum, North Carolina.

Let's see what the USGS Gauge at Bynum says.

 A gauge height over 11 feet counts as a flood...and it is more than 7 feet above current flow.  Note that this is a very wide river, so the actual volume was much more than 7 times...according to the USGS calculation, the flow was near 20,000 CFS, over 30 times the current flow of 600 CFS.

How does the compare to previous floods?

This January flood appears to be a bankfull event that was surpassed in 2008 (the first year of record for Bynum), 2009, and 2010, (but not in 2011 or 2012).  Many of these large floods happen in the early spring, perhaps when the heavy rains fall on an already-saturated watershed.

This is what happened the week of January 13th.  On top of the previous week's rain, there was significant rain on Monday the 14th and Wednesday the 16th.  The storm continued into Thursday, bringing more than an inch of thunderstorm rain (and snow) on top of the saturated landscape.  The Haw river flow peaked soon thereafter, in the early morning hours of January 18th.

Two views on global warming "standstill"

A flash animation from wattsupwiththat:

The view from from Skeptical Science: