U of M News Wire: July 12, 2007

 
Climate changes begin to alter Minnesota’s fish habitat
Increased surface temperatures on lakes combined with decreased levels of dissolved oxygen in deeper waters are reducing the layer of livable water for fish

By Maia Homstad
U of M News Wire

The recent blast of media coverage concerning global warming seems to indicate it’s a late-breaking, newly discovered story, but University of Minnesota professor Heinz Stefan could tell you differently. Twenty years before Al Gore released the Academy Awarding-winning “An Inconvenient Truth,” the U.S. Environmental Protection Agency
(EPA) approached Stefan and asked him to study effects of atmospheric temperature change on Minnesota’s lakes and streams. Since then, he and his students have examined, recorded, and projected climate change effects on bodies of water both locally and nationally. And in case there is anyone left who remains doubtful, their projections of global warming effects on Minnesota water are already beginning to come true.
 
Based on a 25-year history of recorded atmospheric measurements, and current levels of emissions, it is projected that atmospheric carbon dioxide levels will double (2xCO2) in this century. Using these parameters, Stefan and his students projected water temperatures and dissolved oxygen (DO) levels over the next 100 years. Following this model, Earth would experience an average air temperature increase of a mere 3-6° C (about 5.4 degrees Fahrenheit to 10.8 degrees Fahrenheit), but the implications of this change for the aquatic environment are much more significant and ominous.

Global Warming 101
Long before the widely-publicized 2007 report from the Intergovernmental Panel on Climate Change provided the strongest evidence yet of global warming, Stefan and his colleagues knew that the environmental effects of this increase are complex and interdependent. Under a 2xCO2 climate scenario, summer surface temperatures in many Minnesota lakes are projected to rise by an average of 3° C (5.4 degrees Fahrenheit.) Specific temperature changes below the water surface will depend on an individual lake’s depth, wind exposure, and water clarity.
 
Extreme Measures
To make their projections, the water resources engineers at the University of Minnesota St. Anthony Falls Laboratory (SAFL) began by taking recordings from 209 weather stations across the country, which they used to simulate lake temperature, and dissolved oxygen changes under a 2xCO2 scenario. Stefan then worked with John Eaton, Howard McCormick, and the late Ken Hokanson, all fish biologists from the EPA who helped develop criteria for habitat conditions necessary for adult coldwater, coolwater, and warmwater fish. He and his students focused, with help from the EPA, on hydrologic parameters such as water temperatures, evaporation from water surfaces, and dissolved oxygen, and related them to adult fish survival and good growth of fish in streams and lakes. Simulations of climate warming effects demonstrated what they should expect to find: increased water temperatures, reduced ice coverage, less dissolved oxygen, and therefore a drastically changed fish habitat. With these results, the significance of global warming on freshwater fish habitat began to emerge.
 
Less Ice, More Water
After the projections were completed, former U of M graduate student Stephanie Johnson worked with the Minnesota Pollution Control Agency (MPCA) and state climatologists to research records of ice covers on lakes, specifically noting the dates of fall formation and spring ice-out. She found a clear trend of earlier ice-out dates for the past 20 years.
 
She also examined streamflow records, focusing on the timing of snowmelt runoff in streams. Johnson found that although spring runoff was occurring earlier, runoff amounts were smaller, and yet there was an increase in overall stream flows throughout the year.
 
Going with the Flow
In an analysis of data from the U.S. Geological Survey, U of M graduate student Eric Novotny discovered some interesting trends in annual stream flow records of five river basins: Minnesota River, Red River, Rainy River, Mississippi River, and tributaries to Lake Superior. Information was extracted on flow duration and mean annual flow, examining average parameters, as wells as peaks and lows. What he found was an upward trend in stream flow over a 90-year period. But the next question remained:
“How is this related to the weather?” It appears that the overall increase in annual flow is attributable to higher annual precipitation, but not correlated with spring snowmelt runoff.
 
One Big Cycle
Although warmer winters lead to an earlier and smaller spring melt, an increase in summer floods is the result of an increase in overall precipitation. Contributing to higher precipitation are warmer air temperatures. Higher precipitation levels result in a greater base flow in the summer, and frequent snowmelt produces greater baseflow in the winter.
 
A Fish Out of Water
Stefan and his group have worked to apply their studies on these hydrological parameters to implications of climate change on cold-, cool-, and warmwater fish in Minnesota. The minimum requirements for a basic fish habitat were defined by the EPA as suitable water temperatures and dissolved oxygen (DO) levels. Increased temperatures on a lake’s surface in summer, combined with decreased levels of DO in deeper waters, are creating a squeeze effect on summer fish habitat, narrowing it to a reduced layer of livable water, or none at all.
 
Coldwater fish are particularly affected since they are less tolerant of the warmer temperatures near the surface, and will be forced to the bottom of a lake in order to survive.
 
The findings are complex, but definite: Under a 2xCO2 climate scenario, coldwater fish, such as trout or cisco, will be all but eliminated from many free flowing streams. Exceptions are streams in northern Minnesota that have and can maintain strong shading or groundwater input. Lakes in the southern part of the state are projected to suffer the same loss of coldwater fish, with northern lakes experiencing a severely reduced population. Lakes that are temperature stratified throughout the summer are likely to maintain cold water near the bottom, but depleted levels of dissolved oxygen will
make those cold waters unsuitable as fish habitat.
 
Lakes that are vertically mixed by storm events throughout the summer will have sufficient dissolved oxygen, but their temperatures will become too high for coldwater fish.
 
Coolwater fish, like walleye and yellow perch, will see an increase in growth potential, particularly in the deeper lakes. Warmwater fish, such as bass, will have unchanged growth conditions in the Mississippi River and improved ones in more shaded streams. In lakes, warmwater fish will find increased growth potential, depending on the availability of their food source.
 
If the food source is a coldwater fish that has disappeared, predatory warmwater or coolwater fish may not benefit from a warmer climate. Although coldwater species are projected to lose 40 percent of their habitat for good growth potential, total habitat for good growth of fishes in Minnesota lakes is projected to increase, with warm- and coolwater species experiencing all of the gain. For Minnesotans, this may mean a significant shift in the types of fish available in local waters, which has implications for the overall aquatic environment, as well as for human consumption and recreation.
 
Sunny Skies Ahead
Stefan emphasizes that while we work to reduce emissions of greenhouse gases into the atmosphere, we should also focus on preventive measures and adaptation of freshwater systems. For instance, shading water surfaces with various plants would protect fish from the impending danger of future increased water temperatures. Selectively aerating deep and cold water in lakes would help increase oxygen levels. Installing larger storm sewers will help avoid future flooding problems. And it’s not all bleak, as Stefan says, “There are actually some advantages for cool- and warmwater fish in the climate warming scenario. Overall fish productivity in Minnesota is likely to go up, except for the coldwater fish populations which may become drastically reduced.” A shorter ice cover season will result in fewer fish succumbing to winterkill in shallow lakes, due to a lack of dissolved oxygen.
 
Spreading the Word
Taking his results out of the field and onto the road, Stefan has recently given presentations to various environmental groups and government agencies across the state. One positive result of the focus on global warming is that state funding for continued work is forthcoming, allowing Stefan and other researchers at the university to continue their investigations of global warming. Stefan hopes that sharing his findings will motivate Minnesotans to think about how climate change affects the way we live, and motivate us to take steps to protect our environment.
 
For more information, visit www.safl.umn.edu.
 
 
----------
 
Tapping a new pool of doctors
Students interested in rural medicine or from underrepresented groups taste the medical life

By Deane Morrison
U of M News Wire

As an immigrant to the United States from Liberia in 2001, Georgette McCauley has seen more than her share of turmoil. But there's one thing in particular she would like to change in her home country: young women's lack of health information.
 
"I'd like to go back to Liberia someday and educate young women on how to prevent sexual disease and how to take better care of their bodies," says McCauley,
She is one of 23 Minnesota college students in a new joint program of the University of Minnesota Medical School and Mayo Medical School to help increase the numbers of minority, immigrant and rural doctors in the state.
 
Called Minnesota's Future Doctors, the program is the brainchild of two U of M medical students, Gareth Forde and Matt Fitzpatrick. It brings in high-ability students during the summer and the academic year to learn about topics like the science behind medicine and how to take the Medical College Admission Test. This summer's inaugural group has already toured the Mayo Clinic and UMD's Medical School, worked on a volunteer project, and shadowed doctors to see how medicine is practiced on a daily basis.
 
"[Forde and Fitzpatrick] wanted to create future classmates who were more reflective of Minnesota," says program director Jo Peterson. "This project aims at narrowing the disparity and increasing the percentage of persons of color.
 
"The reason that's important is that persons who work with doctors within their same cultural values [and] community of color feel they have better health care, and they continue to work with that doctor."
 
Students are chosen in their freshman year and work with program staff through the rest of their undergraduate careers. They can spend either three summers or three academic years in the program, honing their skills and familiarizing themselves with the needs of underserved populations.
 
Thuy Nguyen-Tran knows such needs first-hand. The daughter of parents who immigrated to the United States from Vietnam, she learned Vietnamese from them.
 
"I know there might not be enough translators for Vietnamese people," she says. "There should be more health professionals who can help spread information [to nonnative English speakers].
 
"I've never been around so many different cultures at once," enthuses McCauley. "It's exciting to hear about the other cultures and to share mine."
 
A student at UMTC, Nguyen-Tran volunteers at a crisis nursery, where she cooks breakfast for children of parents going through some kind of difficulty. Most of the kids are six or younger, a group Nguyen-Tran enjoys because she hopes to become a pediatrician.
 
While Asians are slightly overrepresented among Minnesota physicians (see sidebar), Hmong and Vietnamese are underrepresented. Besides Nguyen-Tran, this summer's Future Doctors group includes three Hmong students.
 
By the numbers:

Percentages of physicians in Minnesota don't reflect the strengths of minority communities
 
American Indian: 2% of population, 0.7% of physicians
 
Asian: 4% of population, 7% of physicians (although Hmong and Vietnamese are underrepresented)
 
Black/African American: 5% of population, 1% of physicians
 
Latino: 4 percent of population, 2 percent of physicians
 
White: 85% of population, 86% of physicians
 
Source: AAMC report 2006 and Minnesota Department of Health 2007
 
For Jonna Maas, a UMM student from Walnut Grove (pop. ca. 500), one of the best things about the program was hearing from medical students. They clued the younger students in on what to expect when interviewing at medical schools to which they've applied.
 
"They told us interview questions to look out for," Maas says. "For example, an interviewer may ask, 'What do you think about [some particular issue] in medicine,' so it's good to be prepared about all kinds of things in the news."
 
Among the hands-on activities for the students was a stint working with a lifelike dental patient simulator (not "dummy," thank you). Guided by advanced dental students, the younger students tried their hand at applying dental sealants and, of course, drilling.
 
Michael Madden, interim dean of admissions at the University's Dental School, exhorted them to be careful with sealants. As most of the sealant material hardens, the top layer remains liquid. And boy, does it taste awful. Message: Get rid of it before the patient's tongues touches it.
 
Otherwise, said Madden, "the patient may gag. Or even leave a deposit of material in your chair for you to clean up, and you want to avoid that."
 
Dental student Katie Cargill says that she has worked before with groups of potential dentists who use the simulators. "You can really tell who has natural ability with their hands," she observes.
 
Besides the introduction to medicine, the students appreciate meeting and getting to know each other.
 
"I've never been around so many different cultures at once," enthuses McCauley, who has just completed her freshman year at St. Mary's University of Minnesota. "It's exciting to hear about the other cultures and to share mine." Another thing that impressed her was a family practitioner she shadowed at a local clinic. "I noticed he kept everything on a very professional level," she says. "He didn't get too personal. He listened very carefully to patients' needs and gave advice."
 
For his part, co-founder Fitzpatrick praises Peterson for her "fantastic" job running the program and finds the inaugural group impressive.
 
"They're pretty inspirational at this stage," he says. "It's nice to think what they're capable of doing."
 
 ----------
 
Growing Concerns
A parenting question-and-answer column with Dr. Martha Erickson of the University of Minnesota

Question:  What can I do to help my 8-year-old grandson overcome a negative attitude?  He loves to play games and draw pictures, yet he is unsure of himself and usually figures things will not turn out the way he wants.  He is being raised by his mother, my ex-daughter-in-law, who comes from a negative family -- always feeling they have been dealt the worst. I suspect that was one of the underlying reasons for the breakup of his parents.
 
Answer:  Your question raises two important issues. Although your primary question is about how to help your grandson develop a more positive outlook, your description of the situation also suggests some underlying issues between your family and that of your son's ex-wife. It sounds like it sometimes feels overwhelming to try to counteract what you see as the negative influence of his mother. Much is written about divorced parents, but less attention is paid to the role of extended family after a divorce. And yet the steady love and support of a grandmother can be just the thing to help a child thrive even in the face of the loss and confusion surrounding a divorce.
         
Here are a few suggestions that might help as you try to encourage your grandson toward a more positive, hopeful attitude:
 
• Counteract his pessimistic outlook with your own realistically positive attitude.  Example is the best teacher, so look for opportunities to demonstrate a positive attitude even in the face of challenges. Let him see that things don't always go perfectly, but will usually work out OK. For example, when you do an art project with him, let him see how you sometimes make a mistake but then laugh and use your creativity to turn it into something different ("making lemonade out of lemons!”)
 
• When he expresses negative expectations, acknowledge those feelings by saying, “I can see that you're afraid it's not going to turn out well.”  Then encourage him to move forward anyway by saying, “I wonder what we could do so that it will be OK even if it's not exactly what we want?”
 
• Real self-esteem comes through the experience of actually doing things well.  So, work with your grandson to develop one special area of competence -- whether it's in the arts, academics, sports, fixing things, cooking or playing chess.
 
• Although your grandson is still very young, it's not too early to begin to help him develop a focus on other people's needs. Engage him in helping you in the church nursery, choosing holiday gifts for people who can't afford them, or going with you and his dad to serve at a soup kitchen. As he matures, stepping outside of his own experience may help him develop a more balanced perspective.
 
• Every chance you get, affirm for the boy how much both of his parents love him.  Although you see things in your ex-in-laws that trouble you, your grandson will do best if you can approach his mother in a supportive, nonjudgmental way -- and if you can encourage positive co-parenting even though the parents no longer are married.  Recognize that there is much that is beyond your power to change, but that the most powerful thing you can do is to be a part of the network of adults who join together to guide, nurture and encourage your grandson through each stage of his development.