GLOBE Scientists' Blog » Climate Change http://globe.gov/explore-science/scientists-blog/archived-posts/sciblog Tue, 31 Dec 2013 18:02:12 +0000 en-US hourly 1 http://wordpress.org/?v= Connecting pollutants and air temperature in the Maldives http://globe.gov/explore-science/scientists-blog/archived-posts/sciblog/2013/03/06/connecting-pollutants-and-air-temperature-in-the-maldives/?utm_source=rss&utm_medium=rss&utm_campaign=connecting-pollutants-and-air-temperature-in-the-maldives http://globe.gov/explore-science/scientists-blog/archived-posts/sciblog/2013/03/06/connecting-pollutants-and-air-temperature-in-the-maldives/#comments Wed, 06 Mar 2013 16:00:16 +0000 GLOBE Program http://globe.gov/explore-science/scientists-blog/archived-posts/sciblog/?p=1602 Continue reading ]]> With climate change, there are many relationships that are understood, and many others that are not.  Dr. Veerabhadran Ramanathan from The Scripps Institute in San Diego has spent the last fifteen years in the Maldives, a nation south of India that is comprised of over 1,200 islands, studying the relationship between air pollutants, cloud formation and air temperature.

The Maldives are a great location for such an experiment because during the months of November through March, the country experiences its dry season with respect to the monsoon, and pollutant heavy air can be seen traveling from thousands of kilometers away from countries like India and Pakistan.  Furthermore, the island nation has a low elevation and is extremely sensitive to changes in sea level rise.

A map of the Maldives.  From Worldatlas.com

A map of the Maldives. From Worldatlas.com

Through the research, Ramanathan and his colleagues discovered that these pollutants are primarily composed of black carbon soot that comes from the burning of fossil fuels and biomass.  With the longevity of the research, they were able to understand that there is a strong heating effect of these pollutants.   But black carbon soot affects more than air temperature – it destroys millions of tons of crops annually and causes human health concerns.  The good news is that this type of emission is easy to reduce due to the face that its lifespan in the atmosphere is short.

Sources of black carbon emission.  From AGU.org

Sources of black carbon emission. From AGU.org

If these types of pollutants are reduced quickly, the long-term negative effects of climate change can be reduced by nearly 50% in the next 20-30 years.  With Ramanathan’s research, The Climate and Clean Air Coalition (CCAC) was established.  The CCAC is focusing on the reduction of short lived pollutants by nearly one third to protect and improve human health and agriculture.

And while the relationship between black carbon soot and warming is better understood, and has recently been presented by the International Global Atmospheric Chemistry Project, the affect the black carbon has on clouds and the type that form is still unknown.  Further research is necessary to understand the feedback between black carbon affected clouds and climate change.

Suggested activity: If you’re a GLOBE school in an area that sees seasonal fluctuations in air quality, you can perform your own research study to see the affect that air pollution has on your local temperature, cloud type and cloud cover.  Start by taking air temperature, cloud clover, cloud type and aerosol measurements and enter them into the GLOBE database.  Then as your database grows, start to examine the relationships that exist between the variables.  Then, be sure to tell us about it.  You can share your future research plans with us through a comment, email or on our Facebook Page.  For more information on Ramanathan’s research, watch this video.

-Jessica Mackaro

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The wolverine: new proposals may renew hope in their survival http://globe.gov/explore-science/scientists-blog/archived-posts/sciblog/2013/02/27/the-wolverine-new-proposals-may-renew-hope-in-their-survival/?utm_source=rss&utm_medium=rss&utm_campaign=the-wolverine-new-proposals-may-renew-hope-in-their-survival http://globe.gov/explore-science/scientists-blog/archived-posts/sciblog/2013/02/27/the-wolverine-new-proposals-may-renew-hope-in-their-survival/#comments Wed, 27 Feb 2013 16:00:58 +0000 GLOBE Program http://globe.gov/explore-science/scientists-blog/archived-posts/sciblog/?p=1595 Continue reading ]]> A couple of years ago, I attended a seminar sponsored by the Climate and Global Dynamics Division (CGD) of the National Center for Atmospheric Research (NCAR) on how climate change is threatening the survival of wolverines (Gulo gulo).  This scientist, Synte Peacock from CGD, painted a gloomy outlook for this ferocious creature after using a climate model to examine changes in spring snow cover and summer air temperatures.    However, recent legislative proposals may make the future a little brighter.

A wolverine. Photo Credit: Steve Kroschel. From U.S. Fish and Wildlife Service

The wolverine, a member of the weasel family, once used to roam central Europe and the Midwestern United States.  These habitats correlated to persistent spring snow cover, due to the need of consistent snowpack for reproductive success.  Female wolverines dig out birthing dens deep in the snow to protect their young from predators and harsh temperatures.  Even so, wolverines are very well equipped to survive in frigid cold temperatures, but have difficulty when temperatures reach above 22°C.

More recently, the wolverine is now found only in the northern boreal forests and subarctic and alpine tundra of Scandinavia, Russia, Canada, and the northern United States due to changes in their habitat.  Regions that once saw significant snowfalls, such as the state of Michigan in the United States, no longer are home to these creatures.

In her research, Peacock looked at three different emissions scenarios to determine what would happen to the wolverine’s habitat and thus the wolverine.  In the scenarios where emissions continue at their current level and do not drop until at least 2050, the future is grim.  Spring snow cover may completely vanish as well as high temperatures during the month of August could exceed 32°C.  These two factors would be detrimental to the creature’s survival.

In the past few years, there have been legislative proposals to include the North American Wolverine under the Endangered Species Act, and a recent announcement  brings the topic back to the forefront.  To date, there are only 250-300 wolverines remaining in the Contiguous United States.  With this legislative protection, the wolverines will be protected from hunting and trapping and give the species the ability to repopulate.  It is hoped that this opportunity would allow the species to continue to thrive.

Suggested activity: As members of the GLOBE community, you have the ability to collect important temperature  and precipitation  data, especially if you reside in the areas where wolverines still exist.  Even if you do not, this type of information is important to other species that are climate-sensitive.  Go outside and collect air temperature and precipitation data, and consider getting involved in the Phenology and Climate Intensive Observing Period to see how climate change might be affecting the growing season of plant species.  Also, consider using this topic to inspire your video for the Student Climate Research Campaign’s Earth Day 2013 Video Competition , which explores how doing GLOBE has improved your local community.

-Jessica Mackaro

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An interesting relationship: soil temperature and climate change http://globe.gov/explore-science/scientists-blog/archived-posts/sciblog/2013/01/30/an-interesting-relationship-soil-temperature-and-climate-change/?utm_source=rss&utm_medium=rss&utm_campaign=an-interesting-relationship-soil-temperature-and-climate-change http://globe.gov/explore-science/scientists-blog/archived-posts/sciblog/2013/01/30/an-interesting-relationship-soil-temperature-and-climate-change/#comments Wed, 30 Jan 2013 16:46:27 +0000 wordpressadmin http://globe.gov/explore-science/scientists-blog/archived-posts/sciblog/?p=1536 Continue reading ]]> It seems common place that warmer air temperature leads to warmer soil temperature. And while this relationship seems intuitive, the effect isn’t always studied, especially with respect to the response from microorganisms. That is why researchers are investigating what happens when the soil temperature increases.

An intricate network of soil microorganisms From: Commonwealth Scientific and Industrial Research Organisation (CISRO).

An intricate network of soil microorganisms From: Commonwealth Scientific and Industrial Research Organisation (CISRO).

The study, performed by scientists from the University of New Hampshire, the University of California-Davis and the Marine Biological Laboratory, examined how microorganisms in the soil respond to temperature changes.  By learning more about that process, scientists could then improve the prediction of how much carbon dioxide is released from the soil.

Microorganisms in the soil release carbon dioxide as a byproduct of how they utilize their food source.  There are two types of food sources: glucose, a simple food source that is release from plant roots, and phenol, a complex food source that comes from decomposing organic matter such as wood and leaves.  Under normal conditions, they release at least 10 times the amount of carbon dioxide that human activities do in a year through the breakdown of these two food sources.  For a perspective on what this amount means, take a look at the graph below, taken from a study from 2010.

Time series of global carbon emissions from fossil fuels.  Image from EPA.

Time series of global carbon emissions from fossil fuels. Image from EPA.

This dramatic amount of carbon dioxide is usually absorbed through the root uptake of trees.  But if the soil warms too much, then these microorganisms are not as efficient at breaking down their food, and thus release more carbon dioxide as they expend the energy.  They are then over-producing, and the trees and plants will not take up as much.  In the short term, it may lead to a positive feedback cycle – where more carbon dioxide is emitted contributing to the rising amount of carbon dioxide in the atmosphere.

However, this same research showed that these microorganisms may have the once again become efficient with their food breakdown after many years of warmer soil temperatures.  After approximately 18 years, the community once again became efficient in their ability to break down food.  This may be due to one of the following things: a change in the community of microorganisms (i.e. the type of microorganism changes), a change in the available nutrients,  and/or species adaptation.

While GLOBE doesn’t have protocols to look directly at microorganisms in the soil, it does have protocols to examine soil temperature.  This is just as important, because soil temperature directly affects many things, such as the timing of Budburst, Green Up and Green Down.  The timing of the phenological processes is important because it informs farmers when to plant crops.   For these reasons, it is very valuable to collect soil temperature data and monitor its changes through the seasons and years.

Suggested activity: Have you collecting soil temperature data?  Did you participate in December’s Surface Temperature Field Campaign?  Have you seen any changes?  We’d love to hear about your experience!  Leave a comment, share with us on our Facebook page, or send us an email.  And make sure you enter the data you’re collecting into the GLOBE database!

-Jessica Mackaro

 

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Trees in trouble: what affect does tree mortality have on climate change http://globe.gov/explore-science/scientists-blog/archived-posts/sciblog/2013/01/23/trees-in-trouble-what-affect-does-tree-mortality-have-on-climate-change/?utm_source=rss&utm_medium=rss&utm_campaign=trees-in-trouble-what-affect-does-tree-mortality-have-on-climate-change http://globe.gov/explore-science/scientists-blog/archived-posts/sciblog/2013/01/23/trees-in-trouble-what-affect-does-tree-mortality-have-on-climate-change/#comments Wed, 23 Jan 2013 16:02:39 +0000 wordpressadmin http://globe.gov/explore-science/scientists-blog/archived-posts/sciblog/?p=1532 Continue reading ]]> Through our trees in trouble series, we’ve examined trees in the Sahel zone in Africa and the United States.  This problem, climate change and dying trees, has been seen on every continent, the only exception being Antarctica, due to the lack of vegetation on the frozen continent.  Scientists have recently found that there is an alarming loss rate of big, old trees, whose ages range from 100-300+ years, in all latitudes.  And both coniferous and deciduous trees are at risk.

Delamere Forest in England – photo from Flickr, user: andrewoliver2011
Delamere Forest in England – photo from Flickr, user: andrewoliver2011

Scientists are well aware of the potential implications that climate has on these trees, what they aren’t aware of is the affect that the reduction in forest will have on the world’s ecosystems.   Trees act like giant lungs, taking in carbon dioxide and releasing oxygen.  Studies have shown that trees take in more than 50% of human-generated carbon dioxide and store it.   Therefore, if these big trees continue to die, there’s more carbon dioxide left in the atmosphere, which can lead to additional atmospheric warming.  Furthermore, if the trees are dead, they cannot provide the key nutrients, such as nitrogen or seeding, to the surrounding soil to allow the forest to re-establish itself after fire or windstorm.

Forest die-off can also affect things like surface moisture and climate classification.  Heat and drought affect each tree species differently, which can result in a long-term shift in the dominant species found in a location.  For example, a forest may become grassland.  This will also affect soil moisture, as there will be no tree canopy to intercept rainfall or prevent the exposure to harsh sun and wind.

But it goes further than that.  Trees provide homes to many different types of animal life, from mammals to birds and reptiles.  As the trees die, these animals are forced to look for a new habitat.   It is feared that as trees die, so will different species that rely on these old trees.

The GLOBE Program has protocols that can aide in the examination of how these forests are changing. Looking at land cover classification while taking air temperature and precipitation measurements can start the foundation for an exploration between climate change and land cover change.  The month of January features a repeat of the Climate and Land Cover Intensive Observing Period (IOP).  With that IOP, teachers and students are encouraged to classify their land cover as well as take photographs.  By keeping these records over the years, GLOBE schools can contribute to studies following forest mortality.

Suggested activity: Participate in the January Climate and Land Cover IOP by establishing or visiting your land cover site.  Submit your photographs and land cover classification to the GLOBE website.

-Jessica Mackaro

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A tale of two extremes http://globe.gov/explore-science/scientists-blog/archived-posts/sciblog/2013/01/16/a-tale-of-two-extremes/?utm_source=rss&utm_medium=rss&utm_campaign=a-tale-of-two-extremes http://globe.gov/explore-science/scientists-blog/archived-posts/sciblog/2013/01/16/a-tale-of-two-extremes/#comments Wed, 16 Jan 2013 17:00:19 +0000 wordpressadmin http://globe.gov/explore-science/scientists-blog/archived-posts/sciblog/?p=1521 Continue reading ]]> Weather extremes have become a common theme in the news headlines the past few weeks. For example, nearly every part of the United States has been experiencing one of two extremes – either frigid cold or record-breaking high temperatures. Places like Arizona and California experienced below-freezing temperatures, which can have potential impacts on the crops grown in these typically balmy regions. In contrast, cities in the Southeast U.S., such as Atlanta, Georgia, had record-breaking temperatures for this time of winter. In Atlanta, the high temperature of 24.4 °C (76 °F) broke the high temperature record set in 1890 by 1 full degree Fahrenheit. Take for example the following surface weather map, showing the vast extremes in temperature across the U.S. on January 13th, 2013:

Surface temperature map of the United States, from the RUC analysis at 1800 UTC on 13 January 2013; Image courtesy of RAL Real-Time Weather Data

Surface temperature map of the United States, from the RUC analysis at 1800 UTC on 13 January 2013; Image courtesy of RAL Real-Time Weather Data

When we looked at the weather map, we were amazed to see such a strong temperature gradient, which is how quickly temperature changes over a given distance.  This was the result of a very strong cold front that moved across the country bringing chilling Arctic air into the heart of the U.S., where you can see some temperatures fell well below -17.8 °C (0 °F).  Ahead of the cold front, temperatures soared, however only until the cold front passed.  If you examine hourly observations from the Southeast U.S., you’ll find some dramatic temperature drops.  For example, in Memphis, TN, the temperature fell nearly 8°C (18°F) in only one hour and fifteen minutes.

Outside of the United States, there are many other countries experiencing extreme weather.  Thousands of people have had to evacuate their homes in Russia after a pipeline burst in the extreme and record cold and Jerusalem, Israel experienced a very rare snowfall last week.  Conversely, Australia is experiencing raging brush fires as the country is gripped by a record-breaking heat wave.  This heat wave has been so intense that road tar has melted and the Bureau of Meteorology had to add two new colors to its temperature maps.

 

Children play in front of the Dome on the Rock during the recent snowstorm in Israel; Photo from Reuters/Ammar Awad

Children play in front of the Dome on the Rock during the recent snowstorm in Israel; Photo from Reuters/Ammar Awad

A map from space showing hotspots from brushfires (red dots) in Tasmania; from NASA

A map from space showing hotspots from brushfires (red dots) in Tasmania; from NASA

While these are examples of weather extremes, they are not necessarily indicators of climate.  It is important to reiterate the difference between weather and climate, as these kinds of weather extremes often get people talking about how it relates to climate and climate change.  Weather is the current state of the atmosphere, the temperatures and weather systems that sweep through a nation over the course of a day or a week, while climate is the long-term average and trend of weather events over many years.  Thus, while these weather extremes are dramatic on both ends of the spectrum, they may not affect a location’s climate unless they occur repeatedly, for many years to come.  It is also important to realize that weather extremes are not uncommon; cold fronts often create sharp temperature gradients and weather patterns can set up to create heat waves or cold spells.  However these extremes may be occurring more frequently and at record-breaking levels due to climate change.

In order to document extreme weather and if it is occurring frequently enough to impact climate, it is important to collect data on a daily basis for many years.  Over time, these data help identify if any long-term trends are occurring.  The GLOBE Program sponsors the Great Global Investigation of Climate project to encourage GLOBE schools to collect regular, daily temperature and precipitation data for this very reason.  The data collection efforts of GLOBE schools help contribute valuable data to monitor weather and climate across the planet.  Just look at this example from Fayetteville High School in Arkansas.  The daily temperature observations of maximum temperature at their school over the past two weeks illustrate the warm up and then extreme cool down that occurred as the cold front passed on January 13th.   These kinds of weather data, recorded over long periods of time, are the key pieces of evidence needed to help decipher if these tales of weather extremes are leading us toward a change in climate.

Maximum daily air temperature (degrees C) recorded by Fayetteville High School in Arkansas between 1-14 January 2013.

Maximum daily air temperature (degrees C) recorded by Fayetteville High School in Arkansas between 1-14 January 2013.

Suggested activity: Have you been affected by this recent extreme weather?  Let us know about it by leaving a comment or sending us an email.  Also, use the recent extreme weather to develop and carryout a research topic, then email it to us at science@globe.gov.  And don’t forget to collect data for the Great Global Investigation of Climate, which repeats again in March!

- Jessica Mackaro and Sarah Tessendorf

 

 

 

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The chicken and egg story of global warming and extreme droughts: A lesson on climate feedbacks http://globe.gov/explore-science/scientists-blog/archived-posts/sciblog/2012/12/19/the-chicken-and-egg-story-of-global-warming-and-extreme-droughts-a-lesson-on-climate-feedbacks/?utm_source=rss&utm_medium=rss&utm_campaign=the-chicken-and-egg-story-of-global-warming-and-extreme-droughts-a-lesson-on-climate-feedbacks http://globe.gov/explore-science/scientists-blog/archived-posts/sciblog/2012/12/19/the-chicken-and-egg-story-of-global-warming-and-extreme-droughts-a-lesson-on-climate-feedbacks/#comments Wed, 19 Dec 2012 22:24:52 +0000 wordpressadmin http://globe.gov/explore-science/scientists-blog/archived-posts/sciblog/?p=1504 Continue reading ]]> I recently read that the extreme drought in western North America during 2000-2004 actually resulted in more carbon dioxide being released into the atmosphere. In the article in Nature Geoscience, it explained that such droughts can further enhance global warming. When a drought occurs, the plants wither and die and no longer uptake carbon dioxide (normally living plants serve as a carbon sink in the global carbon cycle since they consume carbon dioxide). Furthermore, after plants die and start to decay they actually produce carbon dioxide, thereby serving as a carbon source. However, as our planet warms due to carbon dioxide being released at records levels into our atmosphere, climate extremes (such as droughts and floods) are expected to continue to become more frequent and severe (giving rise to the term non-stationarity).

 

A graphical representation of carbon dioxide variations.  From Science Blogs

A graphical representation of carbon dioxide variations. From Science Blogs

So I began to wonder, is global warming causing more droughts?  Or are more droughts leading to more global warming?  Which caused the other first (e.g., which came first—the chicken or the egg)?

While our understanding of the Earth System would imply that droughts alone have not caused global warming, it is now clear that they can further enhance it.  This is an example of a positive feedback loop in the Earth System.  A positive feedback means that one process occurs, causing a subsequent process to occur that results in an outcome that further enhances the first process, and the cycle amplifies and continues over time.  A negative feedback, however, would cause the opposite to happen where the subsequent process results in an outcome that counteracts or weakens the first process.

There are also examples of negative feedbacks in our Earth System.  Take for example when the Earth’s ocean surface temperature heats up, it causes more evaporation from the oceans.  This additional source of moisture into the atmosphere over the oceans can lead to more low-level marine clouds.  Low-level marine stratocumulus clouds are often very reflective of solar radiation, so more of these clouds can thus increase the Earth’s albedo (or solar radiation reflectivity) and thereby cool the ocean surface temperatures.

Another example of a positive feedback; the changing albedo when sea ice melts due to global warming.  From Vancouver Observer

Another example of a positive feedback; the changing albedo when sea ice melts due to global warming. From Vancouver Observer

Don’t be fooled, however, by the terms positive and negative feedback, which may imply one is good and one is bad.  It is actually often the opposite; that the negative feedbacks are what produce balance in the Earth System, whereas the positive feedback loops can act like a runaway train.  Either way, most of these processes are completely natural; however, some can and are being influenced by human activity.  As responsible residents of this planet, we need to do our best to understand how our actions are affecting our home and try to prevent any runaway trains from occurring on our watch.

Suggested activity: Investigate the albedo of various surfaces near you in the GLOBE Surface Temperature Field Campaign and try to estimate if the surface cover changed, would it act as a positive or negative feedback in your local community.

-Sarah Tessendorf

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ENSO Basics: What’s up with the weather? http://globe.gov/explore-science/scientists-blog/archived-posts/sciblog/2012/11/28/enso-basics-whats-up-with-the-weather/?utm_source=rss&utm_medium=rss&utm_campaign=enso-basics-whats-up-with-the-weather http://globe.gov/explore-science/scientists-blog/archived-posts/sciblog/2012/11/28/enso-basics-whats-up-with-the-weather/#comments Wed, 28 Nov 2012 23:33:36 +0000 wordpressadmin http://globe.gov/explore-science/scientists-blog/archived-posts/sciblog/?p=1487 Continue reading ]]> In the first post in this series, we looked at what ENSO is. Remember that the atmosphere and oceans are always moving, and in general, those movements follow a specified pattern. When the movement deviates from normal, to either an El Niño or La Niña, weather conditions in different regions of the world will respond.

But who feels these effects first? Usually, equatorial countries that border the Pacific Ocean. But even these countries can experience vastly different weather conditions. During an El Niño event, Ecuador, for example, may experience severe rain and flooding, while the northern region of Australia may have a drought. As the event continues, the regions affected grow, and countries such as India, Chile and Madagascar will feel the effects.

By studying many El Niño and La Niña events over time, scientists are able to predict that when an El Niño event occurs, during the months of December through February and then in the following June through August, the following areas will see the conditions indicated in the following image:

 

Feeling the effects of a warm episode

Feeling the effects of a warm episode. Image courtesy of NOAA.

Likewise, the relationships for La Niña have been documented  in a similar manner, with different effects felt in various regions:

 

Feeling the effects of a cold episode.  Image courtesy of NOAA.

Feeling the effects of a cold episode. Image courtesy of NOAA.

During the historical El Niño event of 1997, GLOBE students monitored the event by collecting air, water and soil temperature, solid and liquid precipitation and soil moisture data through their corresponding protocols.  These students used historical data as well as their observations to test the hypothesis laid out by scientists in the images above.  It was important to students not highlighted in the regions above to also collect data – they too were testing the hypothesis.

Even though it’s been many years since the 1997 event, this oscillation continues to occur and you are able to investigate the connection between this Pacific Ocean oscillation and your local weather.

Suggested activity: Study the maps above, and create a hypothesis that you can test.  Using historical data, test that hypothesis for a year where either an El Niño or La Niña occurred.  You can find these historical events from NOAA.  Then, be prepared to begin collecting data when another event occurs.

-Jessica Mackaro

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ESNO Basics: What is it? http://globe.gov/explore-science/scientists-blog/archived-posts/sciblog/2012/11/14/esno-basics-what-is-it/?utm_source=rss&utm_medium=rss&utm_campaign=esno-basics-what-is-it http://globe.gov/explore-science/scientists-blog/archived-posts/sciblog/2012/11/14/esno-basics-what-is-it/#comments Wed, 14 Nov 2012 23:01:10 +0000 wordpressadmin http://globe.gov/explore-science/scientists-blog/archived-posts/sciblog/?p=1480 Continue reading ]]> Through many posts here on the Scientists’ Blog, we, in one way or another, discuss ENSO.  ENSO, or El Niño-Southern Oscillation, is a quasi-periodic climate pattern that occurs in the tropical Pacific Ocean.  When the conditions change, the atmosphere responds in many different ways.  In certain locations, it is cloudier and it rains more, while in others it’s clear and dry.  Through our “ENSO Basics” series, we’ll take a look at ENSO in many different ways, such as how ENSO forms, what type of weather it causes, and its connection to climate.  Since we’re currently in a neutral scenario, it seems a great time to examine ENSO and not be partial to one phase or another.  Today’s post will discuss how ENSO forms.

Formation

El Niño is a temporary change in the Pacific Ocean, in the area of the Equator.  Generally, winds in this region blow strongly from east to west (in the mid-latitudes, like where the GLOBE Program Office is located, winds blow from west to east).  Since the winds blow this way over extended periods of time, water in the western Pacific “piles up”.  The water that piles up in this region is warm (approximately 30°C), since the wind pushes the sun-warmed shallow layer of the ocean.  With warmer waters, you tend to see an increase in thunderstorm activity.  So this region that has warmer water, like the northern coast of Australia, sees thunderstorm activity.

The water further east is colder (approximately 22°C) because the deeper water is pulled up to replace the water that has been pushed away. So areas along the western coast of Equatorial South America will see cold temperatures.  Figure 1, taken from the International Research Institute for Climate and Society (IRI) at Columbia University, shows a schematic of the water temperature as well as the accompanying atmospheric circulation.

Schematic of normal conditions

Figure 1. Schematic of normal conditions. From IRI.

In a positive phase, also known as El Niño, the winds that push the water to the west weaken.  Since the winds are weaker or even reverse, not as much water piles up in the western Pacific, so the water slides back toward the east.  With the warmer water sliding back toward the east, not as much cold water rises along the coast.  This results in warmer waters off the coast of equatorial South America.  Once this gets going, the situation continues and strengthens: the warmer waters cause the winds to weaken even further, which results in the ocean warming further, which causes the winds to weaken, which results in the ocean warming.  This is known as a positive feedback, and allows El Niño to grow.  Figure 2, also from IRI, shows El Niño.

Schematic of an El Nino event

Figure 2. Schematic of an El Nino event. From IRI

What happens if the winds actually strengthen? This results in even more warm waters piling up in the western Pacific and even more cold water upwelling along the western coast of Equatorial South America.  This scenario is known as La Niña, or the negative phase of ENSO, and it brings with it different weather patterns.   As with El Niño, there is a positive feedback that happens with the winds and allows the event to strengthen:  the colder waters cause the winds to strengthen even further, which results in the ocean cooling further, which causes the winds to strengthen, which results in the ocean cooling.  Figure 3, again from IRI, shows the schematic for a La Niña event.

Schematic of a La Nina event

Figure 3. Schematic of a La Nina event. From IRI

GLOBE schools have been affected by both El Niño and La Niña.  In 1997, a historically strong El Niño event took place (note: an event is classified as weak, moderate or strong depending upon how far the sea surface temperature departure from normal is over at least five consecutive months).  Students in regions affected by this El Niño took measurements to examine what the effects were locally.  As we continue in this series, we’ll be sure to feature some of the schools making these measurements.

Suggested activity: No matter which region of the world you’re located, you can examine the relationship between your local weather and ENSO.  Taking air temperature and precipitation measurements are great ways to start.  You can then connect those measurements to the Oceanic Niño Index by examining the correlation.  While many studies have been performed using the combination of these observations, it is worthwhile for students to also examine these studies, as this helps makes the connection from local to global.

-Jessica Mackaro

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Non-stationarity: New vocabulary for a changing climate http://globe.gov/explore-science/scientists-blog/archived-posts/sciblog/2012/11/08/non-stationarity-new-vocabulary-for-a-changing-climate/?utm_source=rss&utm_medium=rss&utm_campaign=non-stationarity-new-vocabulary-for-a-changing-climate http://globe.gov/explore-science/scientists-blog/archived-posts/sciblog/2012/11/08/non-stationarity-new-vocabulary-for-a-changing-climate/#comments Thu, 08 Nov 2012 15:59:28 +0000 wordpressadmin http://globe.gov/explore-science/scientists-blog/archived-posts/sciblog/?p=1471 Continue reading ]]> A few years ago I attended a workshop for early career scientists to discuss frontiers in integrated water-climate-society vulnerability and adaptation science. This interdisciplinary area of science focuses on the need for using scientific information to not only identify communities that are vulnerable to climate change, but to also help create effective approaches for communities to adapt to climate change. Since every society needs water to survive, the focus was on water and climate.

Thus, the workshop brought together emerging scientists in the physical sciences (e.g., atmospheric and climate scientists, hydrologists) and the social sciences (e.g., anthropologists, sociologists). I attended the workshop representing atmospheric scientists who study the water cycle, and I learned a lot about the need for interdisciplinary efforts to address problems in the water-climate-society nexus. One of the things I learned was a new term: non-stationarity.

Non-stationarity means that what used to be normal is not normal anymore. It means that our climate system can no longer be considered stationary. The extremes in our climate system of the past, can no longer be considered the outer limits of what our current and future climate system can exceed. For example, a 100-year flood could now be expected to happen more frequently than once in a 100-year period; thus it may become a 50-year flood, or less.

Image looking at the magnitude and frequency of 100 year floods

Image looking at the magnitude and frequency of 100 year floods, from Ohio Department of Natural Resources

The principle of non-stationarity has broad implications. Insurance companies, that base their rates on the likelihood that extreme events will or will not occur, are now having an even harder time doing their risk analyses. Engineers that build dams, levees, and bridges are challenged to build structures that can withstand extreme conditions that we used to not think possible. And communities, especially those in areas vulnerable to sea level rise, drought, or floods, are faced with even tougher potential conditions to adapt to. While the term is just becoming part of my vocabulary, the effects of non-stationarity will be felt for years to come. Thus, accepting this new concept and starting to frame our adaptation solutions around it is crucial as our communities respond to the changing climate.

 

Future drought. These four maps illustrate the potential for future drought worldwide over the decades indicated, based on current projections of future greenhouse gas emissions.

Future drought. These four maps illustrate the potential for future drought worldwide over the decades indicated, based on current projections of future greenhouse gas emissions. From Aiguo Dai, NCAR.

Suggested GLOBE activity: Taking climate measurements regularly, for many years to come, will help provide data to establish climate baselines (or “normals”), and over a long enough period of time will help monitor if these baselines are shifting. You can contribute to these climate data sets by participating in the Great Global Investigation of Climate, the Climate and Land Cover project, and/or the Phenology and Climate project.

If you are interested in interdisciplinary science related to the water-climate-society interface, please see a resource list that was compiled by workshop participants to learn more about programs to get involved in.

-Sarah Tessendorf

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Full Circle Superior Part IV: Changing Superior, Changing Industry http://globe.gov/explore-science/scientists-blog/archived-posts/sciblog/2012/11/01/full-circle-superior-part-iv-changing-superior-changing-industry/?utm_source=rss&utm_medium=rss&utm_campaign=full-circle-superior-part-iv-changing-superior-changing-industry http://globe.gov/explore-science/scientists-blog/archived-posts/sciblog/2012/11/01/full-circle-superior-part-iv-changing-superior-changing-industry/#comments Thu, 01 Nov 2012 18:25:37 +0000 wordpressadmin http://globe.gov/explore-science/scientists-blog/archived-posts/sciblog/?p=1468 Continue reading ]]> This week we pick back up on our Full Circle Superior Series.  In 2010 Mike Link and Kate Crowley chose to walk around the largest fresh water lake in the world – Lake Superior which has shoreline in both Canada and the United States. This 1555 mile/145 day walk was the first ever by a couple and the first to attempt to stay on the shoreline. Because Mike and Kate are educators in their sixties they wanted to deliver important information about the lake to inspire others to care for it. As a researcher and college professor Mike wanted the adventure to have information for his courses and for research institutions around the lake.  This is Part VI in the Full Circle Superior series.  For more information, read Part I, Part II, and Part III.

While there are many issues facing land owners along the shores of Lake Superior, there are other concerning issues, such as the wild rice and fish spawning area on the Bad River Reservation in Wisconsin.

To Chippewa tribes around the Lake Superior basin, wild rice (manoomin) is “the food that grows on water.” It fulfilled a prophecy in the story of the Chippewa tribe’s migration from the east – how they would know they had found their new home. The Chippewa culture bases its history and survival on the natural harvest of fish and wild rice. In 2007, The Bad River Band, a tribe of Chippewa Indians in Northwestern Wisconsin, had to forego ricing because of the low water level. When this happens in isolated years it might allow the reseeding and expansion of rice production, but when it happens over a decade, no one can predict the outcome.

Young wild rice shoots floating on the Kakagon Sloughs, a coastal wetland on Lake Superior, Bad River Reservation, Wisconsin

Young wild rice shoots floating on the Kakagon Sloughs, a coastal wetland on Lake Superior, Bad River Reservation, Wisconsin. Photo taken by K. Rodriguez. From US EPA.

In addition to the impact on wild rice, the natural fisheries of the lake have been impacted by many factors.  One such impact is the toxins that have entered bays with large factories that lacked the pollution prevention filtering. Many of those toxins remain in the water decades later. With water level reduced, the toxins concentrate in the water; the water warms and the fish species that might spawn are prone to failure because of both toxicity and temperature. We had expected to eat more fresh caught fish as we walked around, but the fishing, while good in some areas, has never fully recovered from the earlier combination of overfishing and the arrival of the sea lamprey. The wetlands that we need to be productive were so dry that we walked through many of them without getting our feet wet. This means the food sources for the fish, the habitat for birds, turtles, and other wetland species have had a prolonged period of limited production. We know wetlands are natural filters, but they cannot filter the water if the water does not reach the plants.

Another well documented impact of lower lake levels is  the impairment of shipping..  It speaks to the fact that the issue of low water and the changes in our climate are more than isolated affects, more than the concern a few individuals. Sea Grant, a NOAA administered network of 32 university-based programs that work with coastal communities, discussed this in their 2007 newsletter.

“From an economic standpoint, cargo ships have had to lighten their loads and sometimes vessels have been excluded from harbors. Additionally, power plants at the Soo Locks are running at a diminished capacity.  In August 2012 a 1027 foot freighter went aground within the St Mary River Channel that connects Lake Huron to Lake Superior with the final lift coming at the locks.  The boat not only suffered damage to its hull, it also caused numerous large vessels to anchor in Whitefish Bay and wait for the locks and river to clear for their downbound journey.

For the shipping industry, a one-inch (2.5 cm) water level drop can mean over 250 tons of coal will be left on the dock when a thousand-footer weighs anchor. A two-foot drop means that upwards of 6,000 tons, approximately ten percent of a thousand-footer’s capacity will be left behind. And it’s not like companies can just send more ships to pick up the slack.”

In these areas of concern we were not able to do original research.  Instead, we reviewed existing research, talked to scientists, and then made our observations in light of that knowledge.  On our hike we watched people swimming in Lake Superior like they do in our smaller lakes.  The water temperature was 20° F above normal in 2012.  It is worthy to note that in July of this year, temperatures on both land and water were the highest on record.

Walking along the coast of Lake Superior

Walking along the coast of Lake Superior

Through our trip, our concerns became for the indigenous people of the lake, the resident lake owners and recreationists, the fish, the quality of the water, the economy, and the natural landscape. The continued argument over global climate change  should focus instead on observing what changes are going on and take necessary action. We need to prevent damage to our fresh water and our air. We need to think about the future and not debate whether humans can create a change in the climate – of course we can, just like we can create Chernobyls, BP oil spills, Hungarian toxic sludge flows, and Bhopal plant explosions!

In August of 2012, scientists published a report that worried about the change in the lake effect on communities because it no longer had a cooling effect in 2012.  If the warming continues the lifestyle and the cooling bills along the lake will change dramatically. To put it as plainly as we can: We have seen too many things done to our planet during our lifetime and we think that putting the planet first is a good idea and starting with Lake Superior is a wonderful way to begin the process.

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