Dr. Martin Ross: Expanding the Boundaries of Climate Science

[bananas]

"Every time I expressed an interest in something, books would appear, as if by magic."

http://www.aerospace.org/2014/05/08/dr-martin-ross-expanding-the-boundaries-of-climate-science/

Dr. Martin Ross: Expanding the Boundaries of Climate Science

Corporate Staff
posted May 08, 2014

Interviewed by Lindsay Chaney

Dr. Martin Ross, senior project engineer in the Launch Systems Division, leads research concerning the effects of space systems on the stratosphere at The Aerospace Corporation.

A 26-year Aerospace employee, he is the lead author of a recently published scientific paper in a new journal from the American Geophysical Union called Earth’s Future. The paper, published April 28, is titled “Radiative Forcing Caused by Rocket Engine Emissions.”

In his own words, Ross discusses his new research and what influenced him to become an engineer.

<snip>

As far as rocket exhaust goes, we looked at gases such as CO2 and H2O, and particles such as soot from hydrocarbon-fueled rocket engines and alumina from solid rocket motors. What we found was that CO2 is a total non-issue by orders of magnitude compared with the particles.

It’s disturbing to see in the press discussions of CO2 from rockets like it means anything substantial. Surprisingly, it’s all about the soot.

The other surprise we found was that alumina particles were known to reflect sunlight, so people thought they would cool the atmosphere. But we found that alumina absorbs upwelling infrared energy from the Earth and this absorption wins out over the reflection of sunlight.

So, alumina is a net warmer of the Earth’s atmosphere, exactly the opposite of the commonly accepted wisdom.

This is important because solid rocket motor use is increasing again after the retirement of the space shuttle, which accounted for much of the solid motor use before 2010.

<snip>

Earth’s Future is a new journal trying to establish a new point of view for Earth systems science. It’s a cross-discipline look at how the Earth will look decades from now if current trends continue.

There’s a little bit of philosophy in the journal, which resonates with my interest in academic philosophy. Since 2004, I’ve been an adjunct professor at Embry-Riddle Aeronautical University, where I teach a class in the history of scientific thought.

<snip>

My father read to me in a big green chair every night, this book called “You Will Go to the Moon” and I thought that was the greatest thing ever – going to the moon.

Both of my parents were teachers, so they showered me with books. Every time I expressed an interest in something, books would appear, as if by magic.

<snip>

[bananas]

1. Radiative forcing caused by rocket engine emissions

http://onlinelibrary.wiley.com/doi/10.1002/2013EF000160/abstract

Radiative forcing caused by rocket engine emissions

Martin N. Ross1,* and
Patti M. Sheaffer2

Earth's Future
Volume 2, Issue 4, pages 177–196, April

Abstract

Space transportation plays an important and growing role in Earth's economic system. Rockets uniquely emit gases and particles directly into the middle and upper atmosphere where exhaust from hundreds of launches accumulates, changing atmospheric radiation patterns. The instantaneous radiative forcing (RF) caused by major rocket engine emissions CO2, H2O, black carbon (BC), and Al2O3 (alumina) is estimated. Rocket CO2 and H2O emissions do not produce significant RF. BC and alumina emissions, under some scenarios, have the potential to produce significant RF. Absorption of solar flux by BC is likely the main RF source from rocket launches. In a new finding, alumina particles, previously thought to cool the Earth by scattering solar flux back to space, absorb outgoing terrestrial longwave radiation, resulting in net positive RF. With the caveat that BC and alumina microphysics are poorly constrained, we find that the present-day RF from rocket launches equals 16?±?8 mW?m?2. The relative contributions from BC, alumina, and H2O are 70%, 28%, and 2%. respectively. The pace of rocket launches is predicted to grow and space transport RF could become comparable to global aviation RF in coming decades. Improved understanding of rocket emission RF requires more sophisticated modeling and improved data describing particle microphysics.

Open access.