Courtesy NOAANitrogen is an essential nutrient for plants. So how can nitrogen limit plant growth, given that nitrogen comprises 79 percent of the atmosphere? But atmospheric nitrogen is composed of molecules consisting of two atoms of nitrogen and this form of nitrogen cannot be used by plants.
Farmers have for centuries spread animal manure on fields or plowed under leguminous crops (such as alfalfa which has microbial communities living on its roots that fix nitrogen) to add useful, reactive forms of nitrogen to soils. German ingenuity in the early 20th century invented an industrial process that made it possible for the first time to manufacture plant-usable forms of nitrogen, which made possible the artificial fertilizing of crops.
Manmade production of ammonia and nitrate fertilizers has exploded in recent decades and now vastly exceeds the amount of atmospheric nitrogen converted into reactive nitrogen by microbial organisms around the world. At the same time, the burning of ever-increasing quantities of coal, oil and natural gas converts some atmospheric nitrogen into oxides of nitrogen (NOx). NOx emissions can both increase crop growth and diminish it because NOx gases help catalyze the formation of ground-level ozone and this gas is toxic to plant life.
The huge increases of human-produced forms of nitrogen that are applied to croplands and that are released into the atmosphere and eventually settle out have many unintended consequences. In particular, excess nitrogen washes off of agricultural and urban landscapes and is accelerating the destructive growth of algae in lakes, rivers and coastal estuaries around the world.
The connections between manmade carbon dioxide emissions and climate change are quite worrying and receive much scientific and media attention. Nitrogen pollution receives much less notice but is a dramatic example of how human activities now dominate many of the chemical, physical and biological processes that make this plant so amenable to human life.
The entire nation now has a new ‘normal temperature.’ These climatological temperatures, and other weather parameters, are computed by averaging all temperatures over a 30-year period. These averages are called normal temperatures. These averages serve as a reference point and are used to help us interpret average climate conditions at a particular location. A comparison of today’s temperature with the normal temperature helps us determine if today is an atypical weather day. Private industry also uses these temperatures in the planning. For example, energy companies use the normal temperature for long term planning of energy usage. Agriculture uses this as they monitor a particular growing season.
The National Ocean and Atmosphere Administration’s National Climatic Data Center (or NCDC) calculates the normal weather conditions over a thirty year period for more than 7,500 locations in the United States.
Since this time period is a reference point, we have to define the 30-year period. As of July 1, this averaging period is 1981-2010. Prior to that date, the averaging period was 1971-2000. So, what does this new period tell us?
The normal temperature for the entire US is about 0.5 °F warmer now than it was during the 1971-2000 time period. The normal low temperature for WI is about 0.8 °F warmer now than it was in the 1971-2000 period; and WI normal high temperature is about 0.6 °F warmer. According to Assistant State Climatologist of WI, Dr. E. Hopkins, the new normal high and low temperatures for Madison (which is where I live) are 56.6 and 36.7, which are 0.2 and 1.2 degrees higher than the previous 30-year period.
You can find the new normals for where you live at this site:
Courtesy Andreas Trepte
Climate change. Rising seas. GMOs. Humans have such an incredible impact on Earth's environment that it's clear we're now the dominant force of change on Earth. This situation has even led some scientists to rename this geologic epoch the Anthropocene, or the human epoch. But as we alter, tweak, and pollute more each year, what will it mean for the survival of other species into the future?
According to Dr. Stephen Kress, they can look forward to human stalkers and creepy mechanical scarecrows. Kress began his career in the islands along Maine's coast during the late 60s and early 70s. In response to the loss of bird species diversity on many islands, he decided to start a human-led migration program that would move puffins to some of the islands. Puffins had once been abundant in the area, but their population dwindled due to overhunting and egg harvesting.
Still others accused Kress of trying to play God. “We’d been playing the Devil for about 500 years,” says Tony Diamond, a Canadian seabird researcher who has collaborated with Kress for decades. “It was time to join the other side.”
(same article as above)
Amid the skepticism of fellow scientists and the stubbornness of birds, Kress persevered and now boasts growing puffin populations on a few islands. But after several attempts to set natural protections and population controls in place, including a mechanical scarecrow to ward off predators, Kress and assistants continue to monitor and protect the puffins themselves. It's the only way they can maintain the new populations. After all, in a human-dominated environment, we get all the benefits and all the responsibilities--a job some might conclude is for the birds.
We are as gods and have to get good at it.
Stewart Brand, Whole Earth Discipline
The average temperature of the planet for the next several thousand years will be determined this century—by those of us living today
A new report from the National Research Council concludes that emissions of carbon dioxide from the burning of fossil fuels have ushered in a new epoch where human activities will largely determine the evolution of Earth's climate.
I hope you will check out the links above and start to consider how our decisions will impact conditions on Earth for a long time.
I enjoy working with our team to develop on-line interactive education activities. We are in the final testing of whose goal is to teach about the balance of global water, land coverage, atmosphere and cloudiness required to create a "liveable planet". If you want to play with it and give us feedback - here is the link:
The goal is to make a habitable planet by adding enough water, atmosphere and clouds to reach a global average temperature of about 15°C (59°F). You can mix and match, add or remove.
* Drag (and drop) an item from the right side to the left to add that element
* Drag (and drop) from the left are back to the right to remove that element
* HINT You must put at least 3 clouds by the planet!!
There is a timer to see how fast you can make the planet livable.
It's Friday, so it's time for a new Science Friday video.
Courtesy Science Friday
How would you describe the size of a wind turbine? There's no right answer. Turbines come in different varieties tuned for different uses. Compare the 256-foot-tall Gamesa G87 turbines, found at Bear Creek Wind Park in Penn., with the mini turbines developed by Bergey Windpower in Norman, Okla. The scale of both may surprise you.
Courtesy Science FridayIt's Friday, so it's time for a new Science Friday video. This week,
"What is the future of sustainable architecture? Washington University's Tyson Living Learning Center in Eureka, MO, achieves the Living Building Challenge--a set of green guidelines that measure a building based on its performance. The building's architect Dan Hellmuth, of Hellmuth & Bicknese Architects in St. Louis, and Kevin Smith, associate director of Tyson Research Center, point out some of the Center's greenest features."
And yet, the presence of another garbage island has been declared, in the Atlantic Ocean this time. (The quick Trashlantis disclaimer: it's not really an island or a continent, or something you could even see from the the surface. It's lots and lots of tiny bits of floating plastic. Just thought we'd go over that again.)
The patch spans about 16 degrees of latitude, and it shall henceforth be known as... New Rubbishland.
(Good looking out, Gene.)
One way to determine the health of an estuary is to test some of its “vital signs”. Important vital signs in rivers and estuaries include things that affect the quality of the water for the health of the various living organisms that call that water home. If there are toxic materials, or even too much of a good thing, like oxygen, organism throughout the food chain can suffer.
One such vital sign can be the development in rivers and estuaries of “red tides”. This term is used to describe large “blooms” of phytoplankton in coastal waters. Phytoplankton are tiny floating plants. They obtain energy through the process of photosynthesis and must therefore live in the well-lit surface layer, where they account for half the photosynthetic activity on our planet. “Red tides” don’t have to be either red or associated with tides, but they concern scientists, because they can produce toxins that can overwhelm other organisms in the water.
Courtesy Alex Derr, CMOP
CMOP is studying a plankton bloom that is dominated by one type of organism called Myrionecta rubra. The organism is technically a eukaryotic protist, a single-celled organism that floats in the water column. Under certain environmental conditions, the cells grow exponentially to millions of cells per liter of water within a few days. The cells are red and the shear numbers of them reflect the sun’s light and enhance their red color in the water.
CMOP researchers Herfort and Peterson traveled to Astoria to collect samples of the plankton bloom. They gathered samples in both the dense red water and in clear patches of water. These samples helped them compare the conditions in the water and the influences the red tide organism might have on its environment.
CMOP scientists have already analyzed several samples collected during previous year’s blooms. Herfort and Zuber use molecular biology techniques to look at the genetic fingerprints of these organisms and others associated with the bloom. This molecular work is carried out in collaboration with Lee Ann McCue Ph.D., a scientist from Pacific Northwest National Laboratory, who performs genetic sequence analysis. Herfort said, “Our data will improve our understanding of the ecological impact of Myrionecta rubra bloom on the Columbia River estuary.”
Eventually whatever caused the Myrionecta rubra to grow rapidly will change and they will no longer have a source of nutrients. Peterson stated, “When they die, they decompose and bacteria can feed on the decomposed material. This growth of bacteria then draws down the oxygen in the water around them while they are respiring”. So while the bloom itself is not toxic in this case, here’s where another vital sign comes in: the bacteria’s respiration may have a harmful effect to other species, by depleting oxygen available to them. (Due to a great deal of water flow and flushing in the Columbia River, this is currently not a danger.)
Unanswered questions that CMOP researchers are exploring include:
The CMOP research team wants to start answering these and other questions by using a combination of physiological studies, molecular work, and observations and simulations from their end-to-end coastal margin observatory (SATURN). They hope this will provide clues about the factors that lead to plankton blooms, and ultimately improve the ability to predict these events.
Courtesy United States Geological SurveyWhen I read this story the other day, I thought to myself: why didn't I think of that? Or maybe I did think of it, but as usual no one was listening when I pitched the idea for an action-packed spy movie about climate change. Or were they?
The Central Intelligence Agency does have a bunch of high-powered satellites and other "classified" instruments, so it's possible they've been using them to eavesdrop on my conversations with friends about possible sci-fi movie plots.
What's more likely: they figured out on their own that intelligence-gathering instruments could be really helpful to scientists, who can read detailed pictures of melting sea ice, growing desserts and other phenomena to better understand how climate is changing the planet.
The C.I.A. recently confirmed that it had revived this controversial data-sharing program known as Madea, which stands for Measurements of Earth Data for Environmental Analysis. If you decode that C.I.A. code name, it means that government spies are working with climate scientists to gather images and data about environmental change, as well as its impact on human populations.
Not everyone is convinced that climate change is a real threat to national security, and so some complainers are complaining that this collaboration between scientists and the C.I.A. is a misuse of resources, but what do they know?
Really? What do they know? So much of what happens over at C.I.A. headquarters is top-secret.
Maybe the whole thing doesn't sound that action packed, but I'm telling you, if you had the right actors playing the scientists, it could be a blockbuster. And if you have the right scientists analyzing the data, it might provide really valuable insights into global environmental change.