IAN Seminar Series: Marcus Griswold: Climate Change and Resilience in Aquatic Systems


>So just broadly I’m gonna go over the you know overview of the impacts we would to expect to occur in Maryland as climate changes. What potential metrics or measurements we can look at when we’re trying to detect this change. What are the measures of resilience that we can move forward with in terms of looking at the watershed health and the stream health, as well as potential needs that we need to continue to look for when we’re moving ahead with this. So what’s gonna happen in Maryland? As a result of you know a 2008 impact study led by Don Boesch, we know that sea level is gonna rise 3 to 4 feet in a day to day number of communities and increase of salinity gradients among a number of streams. We’re gonna have a 4 to 7 degree temperature increase, which could be greater in urban areas where there’s a urban heat island affect and that could affect our aquatic resources. We’ll have a negative 10 to a 20 percent increase in precipitation, although the trends are really pushing for a greater increase and I would get rid of that negative and say that we’re positively trending in precipitation. Our September’s are already getting wetter, this year is another record breaking September and our Januarys are getting wetter too. So try to think about those wetter Septembers and wetter winters and how that’s going to affect dynamics of aquatic ecosystems it’s important. We’re gonna have higher runoff in the spring and lower in the summer. So drilling down into the watershed area: I said you know we’re gonna have more winter storms and drier summers which means that you know potentially a lot of runoff in the winter that could affect sediment and transfer of nutrients and less water in the summer, which could mean more competition with ag and our ecosystems. Potentially more flooding, we would have projected to have an increase in a 100 year storms by about 20%. So what we’re saying is a 100 year storm right now could be you know an 80 year storm or a 50 year storm and our 10 year storms, which a lot of people base their aquatic resources you know looking at storm water flows are gonna change and increase by 30%, which means we need to think about how this affects our TMDLs. So how will this affect our streams? You know I think the core point is that our streams will appear more urban. You know all of the data shows that you know climate change is going to mean more intense storms, more intense runoff, so even in streams that have a lot of repairing cover will potentially have higher peak discharges and more impacted ecosystems. In the central western portions of Maryland and other areas as we go west we’ll have potentially a loss of cold water species, as well as flow sensitive species that respond and are sensitive to high flows as well as low flows. Another important aspect that’s not stream related but we have a lot of small wetlands and intermittent or femoral streams that may not be even mapped in the state that are ultimately going to be lost as we you know we change our rainfall regime and lastly we’ll potentially have more invasives coming into this system as we you know have higher temperatures and more CO2, which may allow migration of both you know more trees and more invasive vegetation, as well as more invasive aquatic species like blue catfish. So just to sort of step back real quick and distinguish when we’re discussing how do we move forward and how do we address climate change, you need to understand that there are the mitigation approaches and the adaptation approaches and these aren’t always independent of each other but they both are necessary to reduce the impacts of climate change on ecosystems and human systems so the mitigation approach is what we’re really moving forward with a lot with you know our green house gas reduction act in terms of you know 25% reduction of emissions by 2020 but you know we also know that that’s not going to solve the global problem as what we’re doing in Maryland. So we need to adapt in terms of figuring out what are the strategies to make communities and ecosystems more resilient. So thinking about “what are the physical aspects that potentially would change with climate?” And in our previous video we actually discussed some of these. You know bank erosion is very important you know know. As streams get more intense precipitation they will become more urbanized or channelized potentially and you’ll have less connection with the flood plain and you’ll have a loss of potential habitat. Additionally a lot of these questions are still being asked in terms of the physical changes like you know we don’t know a lot about you know what’s gonna happen with these systems. So that’s why I’m suggesting that we sort of continue to look at the urban systems as an example of what we could expect to see with climate change. Some of the easy measurements you know look at temperature, for instance you know we’re looking here Maryland has been looking at putting temperature probes out in the water in a lot more of their water sheds now for a three month period and looking at how those areas are more or less stressed. So those are potential areas where we could start you know using that long term data to look at you know how are these changing, how are they increasing temperatures and loss of cold water species because of natural processes, or are they impacts between land use and climate change. More important in some of the western portions is PH and maybe acid neutralizing capacity just because there’s you know potentially more CO2 in the air and the way that’s processed and aquatic ecosystems is important as well as how else it’s processed in the oceans and lastly conductivity is the one thing we’ve been sort of thinking about in terms of we have areas where sea level rise is going to bring potentially more salt water into the tidal fresh systems but you also have interactions between urbanization and climate change so you could be squeezing out species that are potentially in that interface such as the dwarf wedgemussel. Next is sort of thinking about you know what do we need to look at when we’re trying to figure out what species are vulnerable in the system and you know some of this will come out in some of our bionic indices but other aspects won’t. So looking at what traits you know might be the most important traits in the socio aquatic ecosystems vulnerability. You know looking at species that have limited movement or capability of movement between watersheds or between stream sections or tributaries you know certain salamanders don’t have very much movement and also certain invertebrates such as you know Scott mentioned mussels. It’s difficult for them to travel between tributaries so those species are particularly susceptible to not only land use changes but impacts from climate change as we get warmer water temperatures. Again you know flow sensitive species, ones that are really responsive to drought, you know there are a lot of indicators out there now that show what species are responsive to you know drying habitat conditions and how can we use those into a better indicator to look at you know potential climate indicators of in streams. Flood plain and ground water dependent species; again we could potentially be losing this ground water connectivity as areas where we’re already stressing water such as the eastern shore we’re already using a lot of the water for agriculture irrigation, or areas where we’re developing in and there’s not enough water available for human use, we’re ultimately drawing down those ground water based systems and reducing the flow for the biota. So it might not be a direct climate impact but it’s one that’s indirect because an increase in temperature potentially results in an increase in water use. Thinking about you know invertebrates I think it’s important to address the winter and early spring emergent species. You know there’s the winter stern flies that live in streams that you know if we get more winter precipitation then we’re potentially gonna be scouring those systems out and loosing those species. And lastly you know another important issue is this threshold change. So we need to look at where are there thresholds between you know cold water to cool water into warm water species and seeing where those areas are most vulnerable to the change based on climate change versus our land use planning efforts you know looking at more comprehensive plans for each you know municipality can factor into addressing you know maintain resilient cold water stream versus streams that we know climate change ultimately create a more warm water system and how do we adapt to that. Another one that you know groups could start to monitor that I would think really contribute to the overall information data base of you know “what is climate change doing? Is it looking at some of the phonology of the systems and looking at how snow melts occurring just simply saying, ok, snow melt occurring earlier this year what are we seeing in the streams?” or looking at “are the trees budding out earlier, “Are we changing species within that riparian zone?” I think you know these phonology indicators are really important and can be easy to measure by just going out in the field and observing what’s going on. You know additionally, if you’re a trout fisherman and you’re going out you know you got lots of fish in somewhere western Maryland or farther out you know looking at when those May fly species are emerging and just, sort of, documenting those and distributing that to your local groups like Trout Unlimited, or a local watershed group would be you know I think a useful fact and now I know in the bay habitats you have to think about you know the mismatch between you know plankton and fish species and how that could be a potentially impacted by climate but in the non tidal systems we have the same potential impact where you know if we have mismatch between may fly emergence and trout populations and trout spawning. There might be some impacts there that may result in loss of species. So going back to you know getting outside of the stream and looking at habitat I think there are some primers that we could sort of think about in terms of what creates a resilient stream side area riparian zone and you know this is a picture of a very large system; this is the Missouri River system and it shows you here that you know during flooding you know this system does; it’s out of the channel and into the flood plain you know I think it’s really important that we consider cases where we can maintain that connection as much as possible. And again we get back to the diverse vegetation. We have a diversity of species in that riparian zone and there are predictions that show you know as climate change, as temperature increases, as precipition changes we’re gonna lose some of our tree species so if we lose some of these tree species then we need to make sure that we have other species within that riparian zone to replace it that are already there or we could potentially be off setting the riparian restoration that we’re already doing and you know in terms of habitat I think you know thinking in terms you have temperature issues in some of your streams, you’re gonna need to try to you know measure deep pools, measure where the pools are deep and where they provide the most habitat for species that are cool water species so when you know the main part of the stream could potentially be warming you still have those refugia that the species can move into. Again you know the bank habitat such as overhanging vegetation and root lines is potentially you know another aspect that will help shade and cool the water. So in terms of the species that would be resilient you know I think you know we don’t know if we’ll see a lot of these stream beds that are completely dry like this but I think you know in the head water streams I think we will potentially see more of this, so we need to look at you know resilient species, those that are drought resistant, or you know they adapt well to the changes in the flow, or should we be looking also at you know the urban species now and the diversity of suburban and urban species and expect that to be what we should see in the future. So there are a number of your really your critical habitats in this area that you know if we want to you know have a resilient water shed we should really be thinking about you know protecting or potentially figuring out how to restore them. You know we have high elevation systems that they’ll be moving upwards as temperature increases Seeps the springs will be affected by ground water withdrawals as well as changes in temperatures. We have same with vernal pools that potentially are stream side, while some are not always stream side, so we need to you know take account of the vernal pools and the habitat they provide in these systems for rare and endangered species and we need to really think about you know some of these other aspects like cool water inflows from the ground water, as well as tributary junctions, where you know we need to think about the conductivity of the systems and our species are you know once they get pushed up to the head waters because of climate and because of temperature increase are they stuck there or can they potentially migrate down and go back up another tributary that may be more resilient to changes in climate so I’m just gonna briefly go over this but I think you know when you’re looking at methodology there are a number of things I think we should consider you know first I think, first and foremost is to protect the reference sites that we have there because if we don’t have those reference sites then we won’t have anything to look at, in terms of what we should be expecting with climate change. I think it’s also this sort of, you know a lot of this I think is coordination and looking at where you can sample along a large corridor within that watershed so we can sort of start to see the responses. You know there are there’s studies that they’ve actually you known seen the actual movement of predatory invasive bass species and they’d be able to use climate change modeling to look at how that’s going to be moving because they monitored along that corridor. So I know there’s the stratified random sampling methodology but there’s also some targeted methodology we can use to look at climate change impacts. As always you know you should always look at you know where we could improve our hydrologic or temperature data, whether it be just putting your station next to a USGS gauge or trying to figure out ways to get that data in another method. And some of these other aspects like you know timing the patches we talked about with phonology but there might you know opportunities to sort of collaborate with other institutions that are you know do the taxonomy on a daily basis or a regular basis and look at you know we might be needing to look at the genus; at least the genus potentially the species to see which organisms are more responsive to climate change, rather than just looking at the family level in terms of the invertebrate population and you know thinking in terms of a lot of the species will be developing faster. Potentially we need to think about looking at the size of the species too as is done in fish populations. So you know based on what I’ve seen in my conversations, I think there are a number of potential needs if we’re gonna look at you know where are the climate change resilient areas going to be? What can we do to address them and what can we be monitoring to look at this into the future? So one of the big ones is that you know there needs to be sort of a vernal pool monitoring network for the state and I think there’s been a lot of push for that but it hasn’t really gone anywhere but I think the fact is that these vernal pool systems and their femoral pool systems together are likely to be you know lost as we increase our temperature and we increase variability and our precipitation. And you know another thing is we could sort of start thinking about what would the climate changes that work look like on the ground and what would some climate smart measures be for people to start monitoring, or you know what are the measures that we should be looking at that would be resilient and you know I presented some of these but you know I’m sure that there are a number of other ones that you know people have thought about already. And you know just as an aside there some things that you know you as a watershed organization can do, or you as a community group, or you as an individual can do to really you know foster a better knowledge of climate change, foster a better knowledge of resilience and this sort of you know move forward with you know making sure that we can you know predict and understand what’s going to happen into the future. You know obviously just basic water conservation principles like reusing our water and reducing our use. Working potentially with the regulatory agencies to look at where the ground water recharge areas are because those are the areas are gonna be important for base flow in your streams. So if we’re developing our water recharge areas, and then we expect to have base flow in our streams in the future there’s some conflict of interest there. Generally we should just coordinate, coordinate with the groups near you obviously and I think that’s the great thing about MTAC as well as coordinate with you know local universities, or consultants to you know if you don’t have to ability to get the resolution that you want, then you know there are universities that are actively looking for grants, actively looking for money to do their research. So if you could tag onto one of their grants and get that data that would be even better. You know for instance the species level and application for your invertebrates or your fish. And you know always you know promote drought tolerant native species throughout your community as well as you know going out there and advocating for all of the things that you know we’re talking about here. And that’s it for now. Are there any questions?

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