Tag Archives: Ecosystems

The Ozone Protocol: A Climate Change Precedent

The following letter appeared in the January 1, 2016 edition of the News and Observer, Raleigh, NC

News and Observer Letter

It’s deja vu all over again reading George Will (“Another false ‘turning point’,” N&O, 12/17) and Charles Krauthammer (“Obama’s legacy of fiction,” N&O, 12/18) whine about efforts to address climate change. Neither one considers the science or the history. In this case, it’s history worth repeating, not avoiding.

When the world faced the destruction of stratospheric ozone, 12 countries sat down in 1977 to plan how to negotiate a planet-wide pact. It took 10 years, and the outcome was the Montreal Protocol on Substances that Deplete the Ozone Layer, signed by just 24 countries. It’s strength was flexibility, proven in the eight revisions made since 1987.

Now 197 countries are party to a protocol that includes monitoring, reporting, and critically, sanctions for noncompliance. Most important, it’s working, as the rates of emissions of ozone-depleting chemicals have dropped, and since 2000, the ozone layer has begun its slow process of recovery.

International agreements can succeed in addressing a global environmental crisis. The fits and starts seen in the attempts to address climate change might work faster if those with a monetary or political stake in burning fossil fuels would cease their misinformation campaigns, aided by the head-in-the-sand antics of Will and Krauthammer.

—Denis DuBay

P.S. See this article by Jennifer Morgan and Eliza Northrop,  “Form AND Function: Why the Paris Agreement’s Legal Form Is So Important” for confirmation that the Paris deal holds real promise, not unlike the situation with the Montreal Protocol when it was first signed my just 24 countries. It was published online December 16, 2015 by the World Resources Institute.

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Plants in Space

Several weeks ago there was a big splash in the media about astronauts aboard the International Space Station (ISS) eating lettuce they had grown in Earth orbit. Having once spent ten weeks on a faculty fellowship at Kennedy Space Center working on potential problems associated with growing plants in space, I was curious about the progress that had been made since I had that experience.

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Cosmonaut Maxim Suraev holds lettuce plants grown onboard the International Space Station.
Credits: NASA

Okay, I was more than a bit curious. I’m also writing a science fiction novel where plants grown in a greenhouse provide oxygen and food for the crew on a long-duration space mission. The reports from the ISS hardly dented the array of issues I’ve had to consider in creating a system that uses plants to provide crucial life-support for astronauts. By contrast, this recent story seemed almost trivial, a novelty. Astronauts had something better to eat for a change than vacuum-wrapped dry food or paste packaged months earlier back on Earth. I know NASA has grown plants in space for years. Is this the first time astronauts have officially eaten something they’ve grown in orbit? Really?

In fact, I have come up with a list of questions I hope to pose to NASA public relations contacts about plants in space. My questions follow below, and if anyone reading this list either has an answer, knows where I can find an answer, or knows who I might ask for an answer, please reply with a comment to this post.

1. Was the recent event on the ISS the first time space-grown plants have been eaten by astronauts in orbit?

I’ve found a tantalizing hint or two of other astronauts or cosmonauts eating space-grown food unofficially. But it seems that most space-grown plants were harvested and frozen or otherwise stored for shipment back to earth. Which leads to my next question.

2. Have space-grown plants ever been eaten by Earth-bound scientists before?

So if the space-grown veggies were promptly shipped back to Earth, did they get taste-tested there? I’ve gathered hints here and there about concerns that space-grown plants might not be safe for human consumption. I have to admit this sounds a bit like the worries about the safety of genetically-modified crops (GMCs). If it grows like a leaf of lettuce, is the same color – green, and looks like a lettuce leaf… Which leads to the next question.

3. Have toxic compounds ever been discovered in space-grown plants as a result of their growth in microgravity?

If it’s a serious concern, and not the wide-eyed speculations of someone who would rather bring food up to orbit from traditional farms back on good old planet Earth, then presumably space-grown plants have been tested for their safety. Has anything been found to justify further testing, or can our astronauts relax and enjoy any veggies they find the time and space to grow up there in the Space Station?

My last question, for now, goes back a bit further than the International Space Station and even the Space Shuttle. I think I know the official answer to this one, but it was a long boring ride (when nothing went wrong anyhow) from Earth orbit to the Moon.

4. Were plants ever grown by Apollo astronauts on a lunar landing mission either on the Moon or on the way there?

Once again, if you know part of an answer to any of these questions, please share. Even if you’re not sure, share your speculations. Or if you know where I might find an answer, or who I might ask, speak up. And thanks in advance.

HURRICANE GENESIS: A science review by Mark Betancourt in Air & Space Smithsonian

I’ve enjoyed Air & Space magazine for years, but an in-depth article by Mark Betancourt in the August 2015 issue goes above and beyond. I expect informative technology reviews and personal interest articles sating my inborn curiosity in aviation and space developments, but this story is one of the best science reviews I’ve read in a popular magazine.

Mr. Betancourt elucidates the state and the art of hurricane science, describing the methods and tools used to ask and answer the important questions. Of course, that’s how scientists operate, figuring out how to devise and conduct the tests required to solve the unknowns. Here we have the story of hurricane genesis focused on those tools and techniques climate scientists have used in the past as well as the new methods used today. But this story goes even further, into the future, laying out the questions we need to answer about how hurricanes begin.

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Eye wall of Hurricane Katrina from NOAA aircraft

Betancourt does all this without forgetting how Air & Space magazine adroitly grabs reader’s attention with personal stories about real people. So we read about the first pilot to penetrate a hurricane in an airplane. Joseph Duckworth, an Army Air Corps flight instructor and unusually skilled instrument pilot, was eager to show his British student pilots the capabilities of the AT-6 Texan aircraft they liked to ridicule. In July, 1943, he flew an AT-6 into a hurricane off Texas’ Gulf Coast, and returned unscathed. A fascinated colleague asked Duckworth to take him into the hurricane on a repeat of his daring flight. He did so, again returning safely.
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Restored AT-6 Texans flying at Oshkosh, July, 2015

Thus began the era of aircraft flying into a hurricane to take measurements of its strength and movement. P-3 Orions and C-130s have done it now for years, but here we taste the future with details of large and small drones used to study hurricanes up close.

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NOAA WP-3D Orion Hurricane Hunter

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Global Hawk outfitted for hurricane duty with NOAA

The large drone is the Global Hawk, 44’ long with a wingspan of 130’, weighing as much as 32,000 pounds and able to stay aloft in and above a hurricane for 18 hours. The Global Hawk is big enough to release dropsondes that fall through the storm sending back measurements.

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Coyote drone dropped into hurricanes by NOAA

At the other end is the Coyote, a three-foot long handheld drone with a six-foot wingspan weighing just seven pounds and capable of short two-hour flights through a hurricane. The Coyote is itself deployed from a manned P-3 Orion Hurricane Hunter.

The Genesis Part

Along with the personal interest stories and latest technology updates, Mr. Betancourt delivers sound science surrounding the still mysterious forces that coalesce to create a hurricane. He starts with three things we understand, evaporation, convection, and condensation. Water evaporates from the warm ocean surface making the air at the ocean’s surface less dense, causing it to rise – convection. As it rises, the air cools and the evaporated water molecules begin to condense into small droplets. When the droplets grow larger gravity forces them to fall back into warmer air below. When this happens, the droplets partially evaporate, cooling the air around them. This newly cooled air continues to fall, being heavier than the warmer air below. This is a classic downburst of rain and cool air, and it replaces the warm surface air mass that fed convection in the first place. Further evaporation and convection is stopped, and the storm is over.

I knew about evaporation, convection, condensation, even downbursts. But I didn’t know downbursts kill the storm.

What does this have to do with the mystery surrounding the genesis of a hurricane? As a cluster of convective storms come together, the middle layer of air through which rain falls becomes too warm and humid for the raindrops to evaporate, so there is no cooling. The downburst stops, or never really gets going, and rather then being cut off, the storms continue to grow bigger. More evaporation leads to more convection across a broad swath of the ocean surface as the storms coalesce and strengthen. A low pressure center builds as the warm air rises en masse. Cool, dry, and dense air from outside the low pressure center rushes inward from all directions, pushing the warm moist air up faster, allowing more evaporation to occur at the warm ocean’s surface, pushing more convection and ever lower pressure. The inward rushing air speeds up, further increasing surface evaporation and convection, and a positive feedback loop leads to a stronger and stronger storm. Bingo, a hurricane is born.

Unanswered questions include what causes a cluster of storms to coalesce rather than stay isolated and dissipate as they normally do, and what is the role of warm ocean surface waters? But thanks to this well-designed story that focuses on the tools, techniques, and unknowns surrounding the birth of hurricanes, those questions come forth with clarity. That’s how science operates. What’s rare is to see this in-the-field process of scientific investigation form the basic structure of a compelling story.

AIRSPACE CROWDING

As a general aviation pilot, a story about increasing conflicts among fliers sharing the skies overhead carries an intrinsic interest with a safety overtone. As a biologist and a birder, realizing the story is about wildlife-human aerial interactions awakens quite a different interest, still with a safety overtone.

Sergio Lambertucci, a wildlife ecologist at the National University of Comahue in Argentina, along with Emily Shepard, and Rory Wilson, wildlife scientists at Swansea University in the UK, outline the evidence in a thorough review of where and when human and wildlife uses of airspace can lead to problems (see Science magazine, 1 May 2015, 348(6234), pp. 502-504).

Lambertucci et al. include on the human side what you would expect, fixed-wing airplanes, helicopters, and of course, unmanned aerial vehicles (UAVs) or drones. But you may be surprised that human use of the near-surface airspace extends beyond aircraft. Buildings, wind turbines, power lines, and antennae also project well into the lowest hundred meters of airspace within which most flying animals operate.

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Piper Cherokee wing over West Virginia headed to Oshkosh

These three inclusive thinkers also remind their readers that less visible life forms exploit earth’s airspace; bacteria, algae, and fungi. I must admit, even wearing my biologist hat I never considered the impact of our use of airspace on microbial life. But aerial microorganisms can serve as condensation nuclei promoting cloud formation. Changes in the abundance and distribution of these organisms as a result of air pollution and wind flow patterns altered by tall buildings can impact precipitation and weather.
 
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Bald eagle over Jordan Lake dam, North Carolina

Key to mitigating adverse impacts of human activities is a better understanding of just how and where and when wildlife use airspace. Beyond the obvious bird migration patterns that can extend across continental and oceanic boundaries, think about the more mundane, daily use of airspace by our avian friends to find food, mates, and nesting space. These smaller scale dynamics require understanding animal movements in the horizontal and vertical dimensions at scales from meters to kilometers, and how these uses change during the course of a 24-hour day.

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Great blue heron over the Apex Reservoir, North Carolina
 
Armed with better knowledge of wildlife habits of airspace utilization we can design and place buildings and other structures to minimize conflicts. Windows can include markers to alert flying animals, the newest technologies employing ultraviolet lights highly visible to birds. Radar can detect approaching flocks of birds and enable structural modifications to limit impacts, such as reducing wind turbine speeds. In selected instances, full-time or time-sensitive airspace reserves might provide the best alternatives.
 
With over 500 hours in the left seat of single engine aircraft, I’ve only come close to a vulture or other bird a handful of times, almost always in the landing or take-off pattern. But as Lambertucci et al. report, there have been over two hundred people killed by birds striking aircraft, and the cost of bird strikes in the U.S. alone exceeds $900 million per year. One year, 2013, saw 11,315 bird strikes. Better understanding of wildlife use of airspace at small and large scales should enable us to reduce these and the variety of more subtle human-wildlife conflicts in our skies.

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A student’s father took me up in his Christen Eagle!

 

DISRUPTION: A review of the climate change documentary

The video opens with the following quote:

“Power concedes nothing without a demand. It never did and it never will.
—Frederick Douglass

This statement and its author tell us much about the documentary that follows. The focus is on action, in keeping with the title itself, Disruption. The target of the action is, clearly in this case, the fossil fuel industry and the political machine that protects and supports it. And quoting Frederick Douglass hints at the central environmental justice theme.

As a scientist, I am nervous when the discussion moves from a consideration of the science to how to achieve political goals. So, yes, I am not thrilled with the documentary’s fuzzy use of the “tipping point” concept, and avoidance of the more accurate term, “positive or reinforcing feedback.” Yes, I am anxious when specific storm events come to characterize climate change rather than global shifts in heat content of the oceans and the atmosphere. Yes, I am concerned with the touch of exaggeration I perceived when methane was described as fifty times more potent a greenhouse gas than carbon dioxide (I believe twenty-five times is more like it). And I don’t understand why they left out sea level rise and long-term climate events like drought.

However, as a parent and a new grandparent I am more nervous with the risks we take doing nothing, or doing as little as we have done for the past decade to avert climate change. The risk is significant, the consequences likely to be severe, and many unknowns exist that could send us spiraling down paths to new unpleasant, perhaps catastrophic “normals” we could find difficult to avoid or change. I don’t want that for my children or their children.

The purpose of this documentary was not so much education as motivation. The clear goal was to spur individuals to take part in the upcoming climate change march in New York City, either directly or in their local community. Given the seriousness of the problem and especially our country’s negligence in taking sufficient steps to address climate change, I can live with a little rabble-rousing. I only wish it were done with more dispassionate logic, but passion is what they hope, and need, to arouse. On that point I have no dispute.

Next to large crowds on the streets, neighbor to neighbor efforts to share knowledge of the causes and consequences and solutions to climate change seem important as well. Consider participating in that type of activity in addition to marching in the streets.