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floods

August climate impacts stories: Hurricane Harvey, other climate change fueled-floods, and more

August 30th: Harvey reminds us that we should treat climate change as we treat other public health threats. That’s the argument in this New York Times op-ed: Harvey, the storm that humans helped cause.

Holthaus-harveyAugust 29th: The most sobering hot-take on Harvey is by Eric Holthaus: Harvey is what climate change looks like.

August 27: Michael Mann offered a clear explanation of the climate change-Hurricane Harvey connection.

Climate change boosts hurricanes through higher and hotter seas say @KHayhoe @AndrewDessler: The relationship between hurricanes and climate change.

August 26: Rapid hurricane intensification, like we’ve seen with Harvey, is consistent with climate change, writes Chris Mooney.

August 25: First tanker crosses Arctic from Europe to Asia-without icebreaker help. Fleet of 15 coming soon.

August 24:Alaska’s permafrost is thawing, and that has huge implications, locally, regionally, and globally. (My colleagues Beth Herndon and Lauren Kinsman-Costello are studying how permafrost melt, wetlands, carbon, and phosphorus interact in the Alaskan tundra.

2017WarmNights_cleveland_en_title_lgAugust 23: As the number of warm nights is increasing, it makes it harder to recover from heat waves.

August 22: Britain’s seabird colonies face catastrophe as warming waters disrupt their food supply. But we don’t know exactly how big problem is because the UK government won’t fund a new seabird census. The last one was done in 2000.

August 20: High Ground Is Hot Property as Sea Level Rises: Climate Gentrification in Miami.

August 19: Climate gloom and doom? Bring it on. But we need stories about taking action, too. (via @ClimateCuddles)

August 16:Humid heat waves that can kill healthy people in hours will affect millions in South Asia in decades.

August 15:

August 14th: 91 volcanoes discovered under the West Antarctic Ice Sheet!!!! This is so exciting on multiple levels, from the pure geo-nerdery to the potential climate change impacts. Geeking out. (Read Andrew Freedman’s article for all of the details, but its possible that (1) geothermal heating associated with the volcanoes will contribute to melting and destablization; (2) melting the ice sheet could enhance volcanic activity as the pressure is released; and (3) the volcanoes will help anchor the ice sheet in place and reduce the possibility of catastrophic collapse. These are not mutually exclusive possibilities.)

 

August 13th: Flooding in Miami now happens every spring tide. Rainfall & storm surges don’t help out either. I liked the headline in the Washington Post: “Flooding in Miami is no longer news – but it is certainly newsworthy.”

August 12th: Sometimes you just have to laugh, so you don’t cry. Talking about climate politics, with humor. Thanks, Stephen Colbert.

 

August 11th: Climate change fueled a mega-rainstorm that flooded Louisiana 1 year ago, and the vulnerable people caught in the flood are still picking up the pieces. Special and important reporting by Climate Central.

August 10th: A new paper in Science shows that European floods have shifted in timing, up to 2 weeks earlier per year, since 1950. What’s particularly intriguing about the study is that the timing shifts haven’t just occurred in snowy regions, but also in places where rainfall is causing water tables to rise and soils to become more saturated earlier in the spring.

August 9th: Erratic weather affects subsistence rice farmers in Madagascar, further proof that some of the worst climate change impacts will be felt by those least responsible for causing it.

August 7th: Peru’s glaciers have made it a laboratory for adapting to climate change. It’s not going well. This is a really nice feature story from the Washington Post.

August 5th: A new report says that extreme heat & weather could kill 50x more people per yr in Europe by 2100 than today. That may be overestimate, but a more reasonable number in the report is that 2 out of every 3 Europeans will be affected by weather disasters (per year?) compared to 1 in 20 today. Heat waves will account for 99% of all the excess deaths predicted, and it’s awfully hard to relocate away from a heat wave.

August 4th: If you are not yet listening to smart & human commentary on climate change, what’s stopping you?

 

August 2nd: A visualization that condenses space and time to tell a powerful story about the local and global impacts of climate change through the 20th century and beyond.

 

A year of climate change impacts, one day at a time

Our changing climate is already affecting lives in a multitude of ways, and the impacts of climate change will only increase as the world continues to heat up. But because climate operates in the background, it’s easy to ignore the magnitude of the changes happening around us, as we are caught up in a daily news cycle and the rhythms of our own lives. 2017 seems fated to be an eventful – and exhausting – year and it would be all too easy to put climate change on the back burner, while facing seemingly more urgent crises. But, the longer we avoid tackling climate change head on, the more dramatic the impacts we are going to be facing.

I quietly launched a new personal project in January, and now that I’m a month in, I’m ready to tell you about it. I’m tweeting one climate change story per day for each day in 2017, with the tag #365climateimpacts. I’m aiming to tweet timely news stories or compelling visualizations across a wide range of climate change impacted arenas, from oceans to ice, from food to energy, from policy to theology, and more. While I’ve tagged the tweets with the word impacts, I’ll cover climate science and climate solutions as well as the impacts of past, present, and future climate change.

My goals for this project are three-fold:

  1. For those of us who are climate concerned, my goal is to keep climate change on the front burner of our collective agenda with daily reminders of the pervasiveness and magnitude of climate change implications and the hope that individual choice and policy and technological solutions have to offer.
  2. For those who are climate cautious or disengaged, I hope that the in the diversity of topics I tweet at least one will make it across your timeline and resonate with you and the things you care about. We know that just piling on facts doesn’t change people’s minds, but finding a genuine connection is a first step towards a real dialogue. As much as a one-to-many, 140-character limited platform lets me do, I hope I connect with you at some point this year.
  3. For those who are engaging with the climate doubtful and dismissive, I hope to equip with you new resources for those important conversations, give you ideas for how to avoid the deficit model of science communication, and encourage you in the work you are doing.

Without further ado, here’s an archive of January’s #365climateimpacts stories:

January 1:
I started the year with this entrancing visualization of 2016 in atmospheric precipitable water by James Warner:

January 2:

January 3:

January 4:
I tweeted this piece by Andrew Thaler multiple times in January – and I’m likely to keep tweeting it, because it’s just so perfect. “When I talk about climate change, I don’t talk about science.

The term “Climate Change” is now loaded with so much political baggage that it becomes almost impossible to hold a discussion across political lines. In stakeholder interviews, people generally understand and acknowledge the impacts of climate change on local and regional scales, as long as you don’t call it “Climate Change”. This has been my experience working in rural coastal communities, which tend to be strongly conservative and intimately connected to the changing ocean.

Which is why, when I talk about Climate Change, I don’t talk about science.

When I talk about Climate Change, I talk about Fishing.

January 5:
A warmer atmosphere can hold more water, so it’s not too surprising that the hottest year on record also had the most precipitable water in the atmosphere. Still it’s nice to see the physics theory borne out in the data.

January 6:
You are reading one of my #ClimateResolutions right now.

January 7:
The crack in this Antarctic ice shelf just grew by 11 miles. A dramatic break could be imminent.

January 8:
Scientists confirmed (again) that global warming never slowed down. (It looks like Yale’s E360 redesign has killed this story, but here’s a webcached version that works as of 22 January.)

January 9:
Hope Jahren Sure Can Write. What I say when people tell me they feel hopeless about climate change.

Scientists like me study carbon emissions, deforestation, ocean acidification, desertification, sea-level rise, glacial melting, landscape degradation, groundwater salination, invasive species, global warming and more. There is very little good news to share. Today’s environmental problems are easily big enough to eclipse our inadequate solutions. When people tell me that climate change makes them feel hopeless, I breathe deep, and then I respond. I don’t answer them because I have a good response, but because we all deserve at least a bad response. Here is what I say.

January 10:
The way I personally counter the despair that reading the latest climate change news can bring is by thinking about all of the technologies and solutions we already have in hand, and how the economics are steadily working ever more in their favor. President Obama makes a strong case for “The irreversible momentum of clean energy” in a policy forum article in Science magazine. I have a feeling Obama (2017) is going to be a highly cited paper over the next few years.

The mounting economic and scientific evidence leave me confident that trends toward a clean-energy economy that have emerged during my presidency will continue and that the economic opportunity for our country to harness that trend will only grow.

January 15:
Days before handing over power to a Republican administration, the EPA managed to complete a mid-term review of greenhouse gas emissions standards for cars – more than a year ahead of schedule. Wired has the story:

By 2025, cars would have to nearly double their average fuel efficiency (a kind of measure of emissions) and deliver, on average, more than 50 miles per gallon (which, for arcane reasons, equates to a real world figure of 36 mpg). The auto industry caved and agreed, with the caveat that by April 2018, the EPA and National Highway Traffic Safety Administration do a thorough review of the rules, and adjust them if they proved unduly expensive or just plain unworkable.

By completing the review early – and finding the standards appropriate – the EPA just made it harder for the next administration to take a step backwards on car emissions.

January 16:

There’s some debate over whether we should really be lumping the Arctic and Antarctic onto the same plot, but there’s no denying that this is a pretty stunning departure from recorded history of sea ice.

January 18:
We knew it was coming, but January 18th is when NOAA and NASA confirmed that 2016 was the hottest year on record, beating out its immediate predecessor.

January 20:
In honor of Penguin Awareness Day (surely, everyone is aware of them already, right?), I posted a link to this scientific article on how changes in sea ice extent during warm and cold periods over the last 50 years affect Emperor penguin survival and chick hatching. From the abstract:

We show that over the past 50 years, the population of emperor penguins (Aptenodytes forsteri) in Terre Adélie has declined by 50% because of a decrease in adult survival during the late 1970s. At this time there was a prolonged abnormally warm period with reduced sea-ice extent. Mortality rates increased when warm sea-surface temperatures occurred in the foraging area and when annual sea-ice extent was reduced, and were higher for males than for females. In contrast with survival, emperor penguins hatched fewer eggs when winter sea-ice was extended. These results indicate strong and contrasting effects of large-scale oceanographic processes and sea-ice extent on the demography of emperor penguins, and their potential high susceptibility to climate change.

January 21:
A stunning visualization of the trends in global temperature over the last 150 years in this temperature spiral, posted by Climate Central.

Global temperature spiral, updated to include 2016 data. Created by Ed Hawkins.

Global temperature spiral, updated to include 2016 data. Created by Ed Hawkins.

January 22:
An informative and nicely illustrated blogpost on climate.gov explaining the role of a strong El Niño in driving the record global temperatures we’ve experienced for the last three years. The takeaway is that while the El Niño has faded, climate change is still going strong and while we might expect a break from the record heat while we’re in La Niña mode, the next El Nino is likely to be even hotter. (If the climate.gov article disappears from the web, here’s a pdf archived version.)

NOAA graph of global temperature anomalies from 1880-2016, with key years noted.

NOAA graph of global temperature anomalies from 1880-2016, with key years noted.

January 23:
This is a stunning visual story of the places from which the first climate refugees are coming. 1000s of people are already being displaced by rising sea levels, increased flooding, and water scarcity, and millions more people are likely to be on the move in the coming decades. (Thanks to ESRI for creating this and to Dawn Wright for sharing it.)
Climate Migrants Story Map by ESRI

January 24:
Flood disasters have more than doubled in Europe, which is in line with what we’d expect given climate change, according to a new report by insurer Munich Re.

Excerpt from the Guardian article.  Click to read the whole article at the Guardian.

Excerpt from the Guardian article. Click to read the whole article at the Guardian.

January 25:
US solar power employs more people than power generation from oil, gas, and coal combined. (Though not for all uses of these fossil fuels as the headline misleadingly implies.) Renewable energies are the future.

January 26:
Climate change is already affecting Ohio. Find out how climate change affects your state, on this fantastic climate impacts site (produced by the Federal Government): https://statesummaries.ncics.org/ (Note: If this site disappears, I have copies of the info for the states where I’ve lived: OH, NC, OR, MN).

One of three key messages on climate change impacts being experienced by Ohio. The others focus on increasing temperature (and risks for urban areas) and increasing drought risks. What are the key messages for your state?

One of three key messages on climate change impacts being experienced by Ohio. The others focus on increasing temperature (and risks for urban areas) and increasing drought risks. What are the key messages for your state?

January 27:
Unsure how things like volcanic eruptions and air pollution play into the climate change we are experiencing? This data visualization from Bloomberg does a nice job showing how we can’t explain historical temperature trends without CO2 emissions, and what roles other factors have been playing in the temperature record.

January 28:
Peatlands are natural storehouse of carbon from the atmosphere — unless they are destroyed. Then, all the carbon goes back up into the atmosphere. Scientists have recently mapped a huge peatland in the Congo basin. It’s estimated to store the equivalent of 20 years worth of fossil fuel emissions from the United States, over an area the size of New York state. Let’s work to make sure it stays protected and the carbon stays in the ground.

January 29:
Are you watching Katherine Hayhoe’s Global Weirding series of videos yet? You should. One thing I love about Dr. Hayhoe is how clearly she explains why a “just the facts” approach won’t work to convince people skeptical of climate change’s reality. That’s the focus of the latest episode of her series.

January 30:

Following on the news that Europe’s flood disasters have doubled in the past few decades, here’s a new study showing that if global temperatures rise by 4°C, the flood risk in countries representing more than 70% of the global population will increase by more than 500%. (Thanks to Richard Betts for bringing this to my attention.)

Average change in population affected per country given 4?C global warming. Hatching indicates countries where the confidence level of the average change is less than 90%. Figure copyright EU, used in spirit of fair use.

Average change in population affected per country given 4?C global warming. Hatching indicates countries where the confidence level of the average change is less than 90%.
Figure copyright EU, used in spirit of fair use.

January 31:
In a month filled with signs that the new US administration will roll back federal comittments to combatting climate change, California is a beacon of light. The state of California, one of the world’s largest economies in it’s own right, is continuing forward with its efforts to decrease its greenhouse gas emissions. As California knows, once the groundwork for a low carbon future is laid, the economics of going backward don’t make sense.

“There’s a whole ecosystem built to reduce emissions,” said Jon Costantino, an environmental policy advisor who previously worked at the California Air Resources Board. “There’s investors, there’s businesses, there’s consultants.”

He added, “To pull the rug out from under that would have a dramatic impact.”

Anne’s top papers of 2016 + 3 she co-wrote

Yesterday, I posted an epic analysis of my scientific reading habits in 2016, but I didn’t tell you about the papers I read last year that made my heart sing. And I didn’t take much time to brag about my own contributions to the scientific literature. So I’m going to rectify that omission today.

My top 3 papers of 2016 are (in no particular order):

Of rocks and social justice. (unsigned editorial) Nature Geoscience 9, 797 (2016) doi:10.1038/ngeo2836

The whole thing is absolutely worth reading (and it’s not behind a paywall) but here’s where it really starts to hit home:

Two main challenges stand in the way of achieving a diverse geoscience workforce representative of society: we need to attract more people who have not been wearing checkered shirts, walking boots and rucksacks since secondary school, and we need to retain them.

Waters, C. N., Zalasiewicz, J., Summerhayes, C., Barnosky, A. D., Poirier, C., Ga?uszka, A., … & Jeandel, C. (2016). The Anthropocene is functionally and stratigraphically distinct from the Holocene. Science, 351(6269), aad2622.

Want an up-to-date, data-rich, and condensed summary of why many scientists think it is time for a new geologic epoch? This is the paper to read.

Wu, Q., Zhao, Z., Liu, L., Granger, D. E., Wang, H., Cohen, D. J., … & Zhang, J. (2016). Outburst flood at 1920 BCE supports historicity of China’s Great Flood and the Xia dynasty. Science, 353(6299), 579-582.

I am a sucker for a good mega-paleo-flood story, and this one ticks all of the right boxes. An earthquake generates a landslide, which dams a river, and then fails, resulting in one of the largest floods of the last 10,000 years and alters the course of Chinese history. Geology, archaeology, and history combine in this compelling story.

Plus, a bonus paper, that was definitely one of the best papers I read in 2016.

Shields, C., and C. Tague (2015), Ecohydrology in semiarid urban ecosystems: Modeling the relationship between connected impervious area and ecosystem productivity, Water Resour. Res., 51, 302–319, doi:10.1002/2014WR016108.

I’m cheating a little bit here, because this paper came out in 2015. But I read this paper in 2015, and then I read it twice more in 2016. That’s how much I like it. Why? Because it’s a really nice illustration of how physically-based models can reveal the complex and unexpected ways that ecosystems and watersheds respond to urban environments. In a semi-arid environment, deep rooted vegetation can take advantage of the bonus water that gets delivered from rooftop downspouts that drain out onto the land. The additional water use boosts net primary productivity, potentially enough to offset the loss of productivity that occurred when parts of the landscape were paved and built upon. But while deep rooted vegetation, native to the semi-arid landscape, can take advantage of the bonus water, grass can’t. It’s a cool story, with implications for the way we develop and manage urban landscapes – and the way we model them. (This paper is open access as of January 1, 2017!)

I was thrilled to be able to contribute to 3 papers in 2016. 

Turner, V.K., Jarden, K.M., and Jefferson, A.J., 2016. Resident perspectives on green infrastructure in an experimental suburban stormwater management programCities and the Environment, 9(1): art. 4.

In 2015, my team published a paper showing how the installation of bioretention cells, rain gardens, and rain barrels on a residential street in the Cleveland area substantially decreased stormwater runoff. This paper represents the other side of the story – the side that is, just as important (if not more so) – how the people on the street responded to the addition of this green infrastructure. In short, getting residents on board with stormwater management is a big challenge that we’re going to face as we scale-up from demonstration projects to widespread deployment of these technologies. (This paper is open access and free to all.)

Bell, C.D., McMillan, S.K., Clinton, S.M., and Jefferson, A.J., 2016. Hydrologic response to stormwater control measures in urban watershedsJournal of Hydrology. Online ahead of print. doi: 10.1016/j.jhydrol.2016.08.049.

Bell, C.D., McMillan, S.K., Clinton, S.M., and Jefferson, A.J., 2016. Characterizing the Effects of Stormwater Mitigation on Nutrient Export and Stream ConcentrationsEnvironmental Management. doi:10.1007/s00267-016-0801-4

I’m thrilled that first author Colin Bell completed his doctorate in 2016 and got two papers out to boot. These papers are the culmination of 5 years of research in Charlotte, North Carolina. In the Journal of Hydrology, we try to disentangle the effects of stormwater management from the overall signal of urbanization across 16 watersheds. It turns out that for the level of stormwater management we see in the real world, it’s not enough to counter-act the effects of impervious surfaces (pavement and rooftops) as a driver of the hydrologic behavior of urban streams. In Environmental Management, we aim to understand the influence of stormwater ponds and wetlands on water quality in the receiving streams. This turns out to be quite tricky, because the placement of stormwater management structures spatially correlates with changes in land use, but based on differences in concentration between stormwater structure outflow and the stream, we show that it should be possible. This echoes the findings from our 2015 paper using water isotopes to understand stormwater management influences at one of the same sites. Colin will have another paper or two coming out of his modeling work in the next year or so, and we’re still analyzing more data from this project, so keep your eyes out for more work along these lines.

Brock Freyer defends his MS on the Mighty Mississippi

Two people, standing behind a boat, with river and bluffs in the background.

Brock and Anne at the end of field work on the Mississippi River, July 2008.

Today, Brock Freyer will be defending the results of his M.S. research. The title of his research project is: Fluvial Response to River Management and Sediment Supply: Pool 6 of the Upper Mississippi River System, Southeastern Minnesota.

Brock’s committee is composed of Anne Jefferson (advisor), John Diemer and Ross Meentemeyer.

The defense is on Tuesday April 23, 2013, at 1:30 pm in McEniry 307 of UNC Charlotte. As Brock is currently located in Alaska, this will be a Skype defense. All are welcome to attend.

Abstract:

In this age of environmental restorations and rehabilitations, the scale and extent of projects have been getting larger and more expensive. In the Upper Mississippi River System (UMRS) the U.S. Army Corp of Engineers (USACE) has begun the task of restoring the negative effects that over a century of river management has incurred. Due to the scale and cost of such projects, it is essential to understand the natural and human processes that have affected the river system. In the UMRS, erosion and land loss are considered the dominant geomorphological trend, but Pool 6 of the UMRS is an exception to this norm. In Pool 6, deposition and land growth in recent decades have allowed the river morphology to begin reverting to its condition prior to intense river management. Through the application of varied chronological data sets within ArcGIS, spatial variations were measured to better understand where and why changes have occurred. A nested study area approach was applied to Pool 6 by dividing it into three scales: a general Pool wide observation; a smaller more in-depth observation on an area of island emergence and growth in the lower pool; and a subset of that section describing subaqueous conditions utilizing bathymetric data. The results from this study have indicated that site-specific geographic and hydrologic conditions have contributed to island emergence and growth in Pool 6. In Pool 6 land has been emerging at an average rate of 0.08km2/year since 1975.  Within lower Pool 6, land has been emerging on an average rate of 18m2/year since 1940. The bathymetric subset has shown that sediments on average have gained 2.41m in vertical elevation, which translates into just under 828,000 m3 of sediments being deposited in 113 years.  By identifying and describing these conditions river managers will be able to apply such knowledge to locate or reproduce similar characteristics within degraded sections of the UMRS. If the observations hold true in other locations, restoration efforts will be cheaper, more self-sustaining, promote natural fluvial dynamics, and ultimately be much more successful.

We are currently preparing a manuscript for publication.

Looking back at the Upper Mississippi River, moving forward

A student and I are working on finishing a project that has lingered for too many years: a careful analysis of the cumulative effects of river management on islands in the lower part of Pool 6 of the Mississippi River, near my hometown of Winona, Minnesota. There will be a MS thesis soon and hopefully a journal manuscript shortly to follow that, but for now, I’m enjoying discovering new and old research and resources on “the father of waters.”

First, check out this 17-minute silent film on the 1927 Mississippi River flood:


For more information on the film made by the Signal Corps in the 1930s, head here: http://archive.org/details/mississippi_flood_1927

Then, check out this 2012 publication from the USGS on “A Brief History and Summary of the Effects of River Engineering and Dams on the Mississippi River System and Delta.”

Finally, there’s a paper just out in Geophysical Research Letters by Frans et al. titled “Are climatic or land cover changes the dominant cause of runoff trends in the Upper Mississippi River Basin?.”

And that’s my afternoon reading sorted.

March Meanderings

Cross-posted at Highly Allochthonous

It all began at the end of February, when I travelled to La Crosse, Wisconsin to the Upper Midwest Stream Restoration Symposium, which was a really stimulating and vital mix of academics, consultants, and government folks all interested in improving the state of the science and practice of stream restoration. I gave a talk on Evaluating the success of urban stream restoration in an ecosystem services context, which was my first time talking about some hot-off-the-presses UNCC graduate student research, and I learned a lot from the other speakers and poster presenters. While the conference was incredibly stimulating, travel delays due to bad weather on both ends of my trip made for a somewhat grumpy Anne (nobody really wants to spend their birthday stuck in a blizzard in O’Hare), so I’ll be thinking carefully about how to plan my travel to the Upper Midwest during future winters. Nonetheless, the view from the conference venue was phenomenal.

icy river and snowy land

View of the Mississippi River from the Upper Midwest Stream Restoration Symposium in La Crosse, WI. Not shown: bald eagles that frequent the open water patches of the river.

March proper saw me give variations of the restoration talk two other times. On the 15th, I gave it as the seminar for Kent State’s Biological Sciences department, and on the 26th, I gave it at the North Dakota State University Department of Geosciences (more about that trip below). In between, I gave a seminar on the co-evolution of hydrology and topography to the Geology Department at Denison University in Granville, Ohio. Students in that department had just returned from a trip to Hawaii, and a very memorable dialogue occured in the midst of me talking about the High Cascades:

“You’ve seen a young lava flow. What would happen if you poured a bottle of water on it?” “It would steam!” “Not that young!”

Closer to home I also hosted a couple of prospective graduate students, helped interview candidates for a faculty position in our department, and went with a colleague to visit an acid mine drainage site about an hour to the south of Kent. In one fairly small watershed, we were able to tour a number of different remediated and unremediated sites, and it certainly lent a whole different perspective to the ideas of stream restoration and constructed wetlands to look at a landscape irrevocably scarred by mining activities.

Orange water flowing from a tube down a hill and into a stream.

Unremediated acid mine drainage flow directly into Huff Run. The orange is iron precipitate.

Wetland plants and a concrete inlet weir.

Constructed wetland as the second stage of acid mine drainage remediation in the Huff Run watershed.

At the end of the month, we finally got our turn for spring break. I ended up with a somewhat epic combination of mounds of work and a big trip to take, possibly the worst combination of the untenured and tenured professor spring break stereotypes (see this PhD comics strip). The first half of the week, I spent in Fargo, North Dakota, home to the famously flood-prone Red River of the North. (I’ve blogged before about why the river so often produces expansive floods.) It was truly fascinating to put my feet on the ground in a place that I’ve read about and watched from afar for years. And my visit was made all the more interesting by my host and guide, Dr. Stephanie Day, a geomorphologist newly at NDSU and who may well unravel some of the Red’s geomorphological peculiarities.

Scientist in foreground, river in midground, background = flat, snowcovered ground.

Stephanie Day, Assistant Professor of Geosciences at North Dakota State University beside the Red River in Moorhead Minnesota. The flat surface in the background is the approximate elevation of the land for miles around.

Looking towards downtown Fargo, ND from the river side of the levee.

Looking towards downtown Fargo, ND from the river side of the levee.

snow and ice covered river, not in much of a valley.

River’s edge view looking towards downtown Fargo. Snow well over knee deep here on 25 March, by my measurements. As all that snow starts to melt, the water will rise.

There’s a pretty good chance we’ll see a major flood on the Red River later this spring, as the >24″ of snow melts out of the watershed, runs off over frozen ground, and enters the northward flowing river. The Fargo Flood page is the place to go to follow the action, and you can count on updates (and more pictures) here as events unfold.

The latter half of my spring break saw me diagonal across the state of Minnesota to my beloved Driftless Area, back across the Mississippi River, and into the state of Wisconsin. I saw my family, finished paper revisions, and wrote part of a grant proposal. Then I flew home, with nary a weather delay in sight.

If March was a tight, recursive meander of talks and trips to the Upper Midwest, then April promises to be a bit anastomosing with lots of different threads woven together to make another month of scientific delight.

The Great Flood of 1913

The 100th anniversary of Ohio’s greatest disaster is just days away. This epic hydro-meteorological event utterly ravaged river towns from Illinois to Ohio and beyond, but it seems like the event has largely been forgotten in history’s annals. Even flood-obsessed me had lived in Ohio for a few months before I even began to piece together the full extent of the disaster. For a crash course in the events of March 23rd-27th, 1913, navigate through this Prezi:

If you want to know more, there’s lots of details at the Silver Jackets’ 1913 Flood website and you can follow along as historian Trudy Bell researches a book on the flood.

After the storm

Cross-posted at Highly Allochthonous

It’s been quite a week. My home in northeastern Ohio got off lightly from “Superstorm” Sandy, compared to places closer to the Atlantic seaboard and in the Caribbean. But still, over 250,000 people lost power due to high wind, especially in Cuyahoga and Lorain counties along the shores of Lake Erie, where huge waves also caused closure of an interstate and damage. Power crews are still working to restore power to tens of out thousands, and most schools and universities were closed for at least one day, if not longer.

NewsChannel5 photo of large waves crashing against shore in foreground, smokestacks in background

Waves from Sandy crashing against the Lake Erie shoreline in Cleveland. Photo from News Channel 5. Click image for link to source.

Large tree fallen in front of house.

A tree down in my neighborhood, which took the branch of another one as it went. This same picture was the one featured on the local paper’s website story about storm damage. Does this mean it was the most dramatic tree to fall in Kent? Whether or not it was, these people got lucky the trees fell away from their house.

There was also some rain. At my house, I got 4.25 inches (108 mm), which is almost exactly what the forecasts predicted. It came as both a drizzle and as heavy rains, but since last Friday afternoon we haven’t seen the sun. Now, northeastern Ohio is supposed to be quite cloudy, but given the local grumbling, this might be a bit of an extraordinary gray and damp cold run. It wasn’t warm rain either, with temperatures neither climbing out of the 40s F (8 C) or dipping below freezing. Isotopic results are pending, but my money is on our moisture source being almost entirely that northern airmass that got itself entangled with the tropical cyclone. Again, any whining about the damp is pretty well offset by everyone acknowledging that we are extremely lucky compared to states to our east.

All that cold rain brought the local river levels way up. There was major flooding on the Cuyahoga River at the downstream end by Wednesday, and the river at its upstream-most gage in Hiram crested on Thursday night. Flow at Hiram peaked around 1900 cubic feet per second (53.8 cubic m/s), which as I eyeball it on the USGS annual peakflow graph appears to be about a 2-year flood. This is actually consistent with my eyeballed estimate of the flow frequency produced by Sandy on Passage Creek, near Callan Bentley’s house in Virginia. I wonder whether that will be consistent for other rivers affected by Sandy.

For me, this was the first chance to the Cuyahoga River in action as it flows through Kent. The river sits in a gorge than separates the two halves of town, and that seems to keep the river from endangering much property in the town. But it did make for a pretty impressive roaring site and sound as I crossed the bridges today. Here are two pictures of Heritage Park in Kent on Friday afternoon about 4 pm. Contrast that with the low water pictures from early June.

Cuyahoga River in Kent Ohio with impressive whitewater as it passes through an old lock.

Cuyahoga River in Kent Ohio with impressive whitewater as it passes through an old lock. Photo at 4:15 pm November 2nd, 2012 by A. Jefferson.

Flooding downstream of an old dam

Note the water level relative to the trees and those vicious rapids downstream of the lock. The dam in the foreground has been taken off-line and turned into a Heritage Park. Photo by A. Jefferson 4:15 pm 2 November 2012.

Lock at low water

The same lock structure as above, except at low water levels. June 2012, photo by A. Jefferson. Note complete absence of rapids downstream of the lock.

Similar view looking downstream past the dam as the picture above. Note how much vegetation is above water here.

Happy New Water Year! For hydrologists, it’s already 2013.

Cross-posted at Highly Allochthonous

Trees with autumn colors on the banks of a river

The Upper Cuyahoga River as it might look about the time of the new water year. Photo by Ohio DNR (click image for source). A 40 km section upstream of Kent is a state scenic river and I really want to canoe it.

There’s nothing particularly deterministic about starting a new year on January 1st. Our wall calendars happen to do so because of the circumstances of history. For hydrologists in the northern hemisphere, January 1st is not a great time to declare one year dead and a new one born. So instead, we transition between years on the 1st day of October. October 1st, 2012 marks day 1 of the 2013 water year. But, why?

Many hydrologic analyses involve calculating statistics on an annual basis. We might want to calculate annual streamflow to determine how much drier 2012 was than 2011. Or we might want to look for trends in the size of floods. For the example of flood statistics, the most common way to get a time series of floods is to identify the largest flood occurring in each year. This “annual peak flow” record is then used within the framework of a probability distribution function to assign a probability of given size flood occurring in any one year. (Problematically, this has been called a “flood frequency distribution”, leading to unnecessary confusion on the part of the public, but I digress…)

We use only the largest flow each year to calculate statistics because it avoids statistical complication. Principally, we want to ensure all of our events are independent of each other. Let’s say there are two days with really high flows in a year. The highest flow is 27.8 m3/s and the second flow is 24.1 m3/s. If the first measurement was made on January 29th and the second one was from March 18th, then these two data are independent (i.e., not the same flood). But if one is from January 29th and the other is January 30th, they are clearly not independent and should not both be used to calculate statistics as if they were. So, we try to avoid this dependence issue by using only the largest flow each year.

Here’s where we come back to the idea of the water year. Let’s use an example from my local stream gage – the Cuyahoga River at Hiram Rapids. There was a big flood on December 31st, 1990 – the biggest flood of the whole year – reaching a peak flow of 71.4 m3/s. On January 1st, 1991 the water was still high – 66.8 m3/s. After that excitement, the rest of 1991 was pretty dry and flow never again gets anywhere near as high, peaking at 25.0 m3/s in early March. How do we calculate the statistics? If we used the calendar year as our basis, we’d end up double counting that late December flood and we’d throw our flood statistics off.

Instead, hydrologists use October 1st as our cut-off date. In many parts of the Northern Hemisphere, summer is a period of low streamflow, driven by strong evapotranspiration and atmospheric circulation patterns. (A prominent exception to the lack of summer flooding is when tropical cyclones make landfall.) In winter, rain-on-snow can produce large floods in some regions, while decreased evapotranspiration and more frontal storms increase the chances of flooding in some southern regions. In the spring, seasonal snowmelt produces flooding in northern and alpine regions. That leaves the autumn as the period least likely to have frequent flooding. Also, because evapotranspiration is subsiding with cooler temperatures, soil moisture and stream flow don’t tend to be recovering from their low points in the summer. So autumn is a time of transition and a time when extremes are unlikely. The graphs below illustrate this for my local stream gage, but similarly shaped distributions would likely exist for many other gages in the US and beyond.

Thus, it’s a perfect time of year to the clear the books and declare a new year for hydrologic statistics. And it’s got as much or more physical rationale than when we change the calendar on the wall. Happy New Water Year Everyone!

Bar graph showing months with the greatest frequency of flooding in December-April

USGS data on annual peak flows for the Cuyahoga River at Hiram Rapids (gage #04202000) illustrates that summer and fall have the least frequent big floods.

March has the highest discharge, July and August have the lowest.

Mean monthly discharge for the Cuyahoga River at Hiram Rapids shows that summer is the period of lowest flow and that by September and October average discharge is starting to increase.