 The recording is now recording. Let me do a quick intro for those tuning in to the video later on. I'm Nick Lund from Maine Audubon. With me is Dr. Catherine Allen from the University of Maine and we are talking about climate change in the Gulf of Maine. I'll turn it over to Dr. Allen in a moment. She will go through her presentation and we're gonna save questions for the end. If you have questions, please type them into the Q&A box. You can see that down along the bottom of your screen on the two little speech bubbles and we will save time for the end for those questions. I think that should be it. This will be available via recording on our YouTube channel afterwards and that's all. Dr. Allen, welcome and take it away. Thank you so much. Let me get my slides up. Can you see everything? Yes. Wonderful. Well, it's a real pleasure to be here with you today. I am excited to share with you a little bit of the work that I've been doing here at the University of Maine and I will also, before I launch into that, be giving a bit of an overview of how the Gulf of Maine came to be and what's been happening from a broader perspective and then maybe what kind of insights that might give us into the future. And I am a paleo-synographer, which is a bit of a mouthful, but it means someone who studies the ocean and in particular the history, the long-term history of the ocean and going back before instrumental records. So I am a geologist by training and so you're gonna get some geology here, which you may not have been bargaining for, but I promise it will be worth it and highly relevant. I wanna start with the main message that from 2005 to 2019, over 90% of the heat from greenhouse warming has gone into the ocean. Some of you may recognize this image. There are many iterations of it, including in the most recent IPCC report, but really in terms of Earth's energy budget, there's a lot more energy being trapped within the Earth system over the recent decades. And like I mentioned, over 90% of that heat has gone into the ocean, into the upper ocean and increasingly into the deeper ocean. And if that heat had not gone into the ocean and had stuck around in the atmosphere, things would be a lot hotter where we live than it is currently. So we owe a lot to the ocean for taking the biggest hit here. And but I'm gonna be talking about how this fits into long-term Earth climate evolution and specifically with a view, with a focus on the Gulf of Maine. And I'm gonna be talking a little bit about how the pace and the magnitude will depend on what humans do next. Really, it's up to us. And I'm not here to spread doom and gloom. There is a lot that we can do and then we already are doing. And I want to share some of the science, the underlying science with you. The three parts to the presentation today, I'm gonna be talking about the underlying geology of the Gulf of Maine because it's really important and it really affects the conditions that we experienced today in this region. And then I'll talk a little bit about the modern oceanography, the observations that have been ongoing since humans have been present. And paleoceanography will round out the third part with what we are doing to learn more about the long-term trends in the Gulf of Maine and how the last century or two fit into that or not. And then I'll say a word or two about what kind of future work is in the works in store. Starting with the underlying geology. This image is a bathymetric map of the Gulf of Maine. I generated it using a global compilation of multi-resolution topography data. And you can see that the Gulf of Maine is semi-enclosed. It's surrounded by Cape Cod to the Southwest and our familiar coast of Maine to the Northwest and then Nova Scotia. And then there are some shallow areas that are essentially isolating partially the Gulf of Maine from the rest of the Atlantic Ocean. And these physical parameters affect the flow of water and nutrients and organisms in and out of this really important, really beautiful, really productive ocean region. Now, how did the Gulf of Maine form in the first place? Well, a very quick geology lesson. You may remember any of you who've studied geology in the past, hundreds of millions of years ago, there was a supercontinent called Pangea. And so Pangea was formed when continents were all assembled. They all crashed into each other. And during that process, there were several terrains or crustal blocks that sort of were sutured on or docked on to what is now North America. So if you drilled down into the Gulf of Maine, into the bedrock underlying it, sorry, that's my dog. You would find different terrains that are connected to each other and that form the basins, the underlying basin that holds the Gulf of Maine. And that is crustal rock. That is continental crust. And it's bounded on the outer portion by oceanic crust. Now, when Pangea broke apart, these terrains were rifted and faltered. There was a lot of stretching. There was a lot of basins that were formed. And then the oceanic crust extruded from the mantle and then cooled and hardened into what is now the oceanic crust as that whole process was happening, as North America was sort of waving goodbye to Africa and Europe. And on a longer time, sorry, on a broader perspective, you can see the, can you see my mouse when I'm wiggling it around? Yeah. Yeah, wonderful. You can see that here's Maine, modern day position or modern day geography imposed upon these paleocontinents. And the Atlantic Ocean opened. And then when that fully opened to the modern configuration, we are left with this kind of geometry. And you can see, you probably recognize, this is the modern day Gulf of Maine. And I have drawn a transect, a line from A to B from the continent here out into the middle of the North Atlantic Ocean. And what I wanna point out, the whole reason I'm going through this geology point is that a profile drawn from A to B, and here's Katahdin for scale. If you can see that little pointy bit on the continental block, Gulf of Maine is extremely shallow. And you don't really appreciate this in traditional maps. But if you follow this point from A to B from the Gulf of Maine out past the Northeast channel down into, down the shelf slope and rise, the North Atlantic Ocean is quite deep and it can get down to several thousand meters deep. Whereas the Gulf of Maine, the deepest part of it is just under just shy of 300 meters deep. And so that has two major consequences. It's waters refresh or flush relatively quickly. It's a tiny bowl connected to a giant bathtub, right? So it can be, its conditions are able to change and they're strongly influenced by waters that are flowing in and out of it. And the second major point is that it can also be really strongly influenced by atmospheric warming and cooling. I mean, it's this shallow, I wouldn't call it a puddle, but it's a very wide and relatively shallow compared to the North Atlantic Ocean body of water that can be strongly influenced by the atmosphere. And you can see the deepest point in the Gulf of Maine. This is in George's Basin sort of outboard on the outboard side of the Gulf of Maine. Even that is still dwarfed by our neighboring water masses. And so this is part of the equation when we're looking at what's going on today. Another major geologic factor is that the Gulf of Maine was glaciated. So about 20,000 years ago, the entire Gulf of Maine we think was full of ice. The Laurentine ice sheet covered much of Northern North America. And it also extended across Maine and New England and the Maritimes and into the Gulf. And it left a major mark out there. This kind of work has been going on, this understanding, this history has been going on at you Maine for several decades now. This is a map produced by George Denton and collaborators that shows Maine. And so these flow lines from this huge body of ice that used to be present in this area. And then there are ice streams sort of jetting out into, oops, into the North Atlantic. And then icebergs breaking off and flowing out into the ocean. This was the situation, geologically speaking, not that long ago. And another interesting point is that when this area was glaciated, a lot of water that used to be in the ocean evaporated and was locked up in ice on land. And so sea level was quite a bit lower during that time. As a result, some of these areas, including Georgia's bank, grand banks were actually not underwater. They were sub aerial or they were able to grow, have peat bogs and things that were able to accumulate out there. So the world looked quite different 20,000 years ago and the ice left a major mark as those of you who've hiked around Maine or driven around Maine and looked at our landscape, the signs of that ice are just everywhere in the shape of our islands off the coast in the shape of Katahdin, that's been sculpted by that ice and it's also equally dramatic in the Gulf of Maine. Now the ice receded or melted back in several steps over several thousand years and from its most extreme position that's farthest out, it then stepped back, perhaps having some ephemeral ice shelves at different stages but it eventually melted back and back and back to the present coastline and then ultimately back up into Hudson Bay area. In the process of all that melting back, the ice left lots of material within the Gulf of Maine. Almost all of the sediment that is in the Gulf of Maine has a lot of the underlying sediment has something to do with glaciers. There's a lot of glacial material till the really coarse, poorly sorted material that is just dumped out first when ice is melting back to proximal and transitional and then ultimately distal glacial marine sediments, they're layered on top of each other like an evolving cake and then what's shown in this image is one location within the Gulf of Maine that is a transect that used sound waves that from a ship that were sent down to the sea floor and the bouncing back of those sound waves was interpreted to indicate different lithologies or different rock types or sediment types underlying the sea floor. So the shape of the Gulf of Maine, the bathymetry of it, the sediments that are filling it and ultimately creating different habitats for organisms to live all have to do with this geologic history. And a lot of what I've been studying is that transition from glacial to interglacial conditions or to the modern warmer mode of climate. The sea floor in the Gulf of Maine is fairly complex that their glaciated shelves are heterogeneous and notoriously difficult to map. This is just one example from my colleague, Joe Kelly at UMaine of a side scan sonograph. Again, this is just one of the many ways that marine geologists use sound to map the sea floor, but it shows that it's very patchy. There are lots of different places, different types of material that you can find within a small area. And so there's quite a lot of work that needs to be done to understand what's going on down there. The big picture is that assembled from lots of work of several scientists working over several decades is that there is George's Bank is a largely sandy area that's sort of scoured by currents and these orange bits of some sort of gravelly areas. And then the inner bit is mostly clay where these deeper basins are filling up with finer grain material. And then there's the Northeast Channel which is an area of exchange of intermediate sort of depth slope waters with the Greater Atlantic where these waters are coming in and out. And this landscape or the seascape I guess is a result of both the underlying bedrock and then the later glacial processes that then shaped this. And then ultimately on top of that are layered the modern sedimentation from open ocean processes such as plankton living and dying in the water column and building up on the seafloor through time. This is just a zoomed in image of the seafloor around Monhegan Island. And this is showing a potential site that was assessed again by colleagues at UMain for not floating but for potentially as a wind energy area. And so the underlying rock types have to be mapped and you have to consider where is it safe to work and what conditions are present so that this underlying geology matters quite a bit depending on what you're hoping to do what you're hoping to achieve. And finally, I'll mention that in terms of the underlying geology over many years people have been working to understand how sea level has changed in the Gulf of Maine through time. And on this figure it's shown time on the X axis in calibrated years before present zero being the present. And then on the left-hand side of the graph that would be the glacial pre-glacial period where there was a lot of ice on land where the Gulf of Maine was full of ice and then we're documenting that melting back and then rising and changing sea level. So that process of changing sea level has affected both offshore and onshore. So where we live on land, actually for a time you was flooded with ocean and was accumulating marine sediments. So there's something called the Presumscot formation that is present all the way up to Bangor all the way up to where I live. And so that flooding of the land surface and then that gradual adjustment of sea level to what it is at present, this is that elevation of zero that's today, MHW means mean high water and that's in meters. And so that that changing sea level ultimately affected what was happening and what was depositing on this landscape. And so there was rapid accumulation of glacial sediment and then there was erosion of that sediment when the sea levels dropped. And then, let me go back. And then ultimately we're left with sort of the modern coastal rocky zones and then there's a lot more fine-grained material accumulating offshore. So all this is to say that there are a lot of long-term processes that have shaped this Gulf of Maine region. And what we're left with is this really complex relatively shallow basin that is filled with water masses from diverse sources. And any shift in the balance of those sources can really affect the conditions within the Gulf both for sedimentation purposes, for what ends up accumulating on the sea floor and also for the ecosystems and the organisms that are living here. That was your geology 101 at the Gulf of Maine. I'm gonna move on to the modern oceanography. So now that we've got our underlying structure sort of outlined, now I'm gonna shift a little and talk more about how the water is flowing within the modern system and also what kind of energy and balances there are. Today, the Gulf of Maine is filled by water that comes from different sources. Relatively warmer, saltier Gulf stream water comes up from the south and ultimately mixes in to other water masses and enters the Gulf of Maine via the Northeast channel. There is also some shallow shelf water. So this is called Scotian shelf water coming that's strongly influenced by riverine inputs. And so that's sort of a freshening influence that we get that freshens arctic sourced water ultimately that's coming down this area. Those are two of the three. And then the third is this Labrador slope water that comes down along the slope, appropriately named, comes along this slope and also enters the Gulf of Maine through the Northeast channel, this light blue. So these water masses all have slightly different properties. So I mentioned this one is slightly warmer and saltier, this one is slightly, can be slightly fresher with the riverine inputs in terms of the shelf water. And there also can be varying levels of nutrients that are delivered by these water masses. So any changes in these inputs can really affect this mixing bowl of the Gulf of Maine. Ocean temperatures in the Gulf of Maine have been a really strong point of interest for quite a while now. And I'm gonna review how we measure ocean temperature, what we know so far and maybe what we don't know yet what we need to keep working on. At the moment, we have many tools that are at our fingertips for measuring ocean temperature although some of them can be a lot of work going out on ships, for example, there are sensors that are deployed regularly from ships that measure conductivity which is a measure can be translated into salinity, temperature sensors and depth sensors. That is one way we can learn about changing ocean temperatures. Increasingly, the oceanographic community is relying on automated or robot sensors, including floats, buoys and gliders, sort of these devices that we can release into the ocean that can then send data back over different time scales. That has been transformational in terms of our understanding and the amount of data that we as oceanographers can now examine. And then satellites are another really important source of information because they can measure the temperature of sea surface of the ocean surface. And there was a paper in 2015 that made quite a big splash in you so to speak of this trend that was observed between 2004 and 2013 that the Gulf of Maine was warming more rapidly than much of the rest of the global ocean. And this kind of sparked a lot of interest in understanding what's going on here and why. A couple of things to keep in mind just regarding this one sort of soundbite that was produced is that the satellites measure the ocean's skin temperature. They are only able to access through that method, the very, very couple top millimeters of seawater. And it's incredibly useful because we can get these huge maps of properties that would just be impossible with we don't have as many ships or we don't have as many oceanographers as we would need to get that kind of coverage both in space and time, but it is limited to just the surface of the ocean. So it's not really the whole picture. And then it's just a short time period that was initially being studied. And I wanna emphasize continued monitoring is needed, especially below the sea surface because there's a lot going on down there. That's where most of the heat is going and most of the heat is accumulating there. It's passing through the sea surface, but a lot of the heat in our earth system is already left the surface, it's on its way. At the University of Maine, there's been a group that has been working for several years now led by Neil Pettigrew. And there are other, there are colleagues at the New Hampshire and elsewhere that have sort of a network of buoys that are monitoring and have been monitoring conditions in the Gulf of Maine over decades, which is so important and so useful. And this is just really a rich source of information. For example, there's a buoy can be deployed out in a location that the oceanographers choose. And then there can be an array of sensors on a wire that are just basically hanging below the floating portion. And those sensors can be continuously collecting information at different water depths, and then those can be examined through time. And what I'm showing in this diagram, these are publicly available data. You can download them and play with them too. The link is here. These are from the physical oceanography group at UMaine. And this is a buoy from Jordan Basin in the Gulf of Maine, which is a northern basin. And you can see that the temperature swings, the temperature and degrees Celsius through time, the surface ocean changes hugely on a seasonal basis. I mean, we all, we live in Maine or a lot of us listening, I'm assuming are living in Maine. And we understand this that winters and summers have very, very different temperatures where we live. The same is true for the surface ocean. It's a little, the temperature changes are more muted. So the surface ocean is shown here in red. And then the deepest part, the deepest part of the Gulf of Maine, and at least in this location at this buoy, the temperature swings are not quite as large, but they are also varying on an annual basis and there are also trends visible through time. And so it's really important to look at the whole ocean, both in space and depth, to understand what, to understand this warming. A recent compilation of both observations and modeling results shows that Gulf of Maine, bottom water on average is also, has also been rising. And since 1960, and so that, that is a sign that it's, this trend is not just skin deep, it's, you know, it's bottom to top. There's warming that is occurring and that it's persistent. It's, you know, there may be year to year changes. You know, it's not a completely steady rise, but the trend overall is up, both in the surface and in the deep. Another recent paper that came out from a group at UMaine, just is discussing why the Gulf of Maine is warming. Now, what is the role that the shelf slope and Gulfstream water masses are playing in this overall warming that we're seeing? And basically, I can distill it down into a couple of major points that this paper and also other studies have made. Gulf of Maine is warming because it's gaining heat from the atmosphere and it's gaining heat from ocean currents. And those two things, those two processes together are causing the Gulf to warm. And the reason it's warming so fast compared to a lot of other ocean regions is still being investigated. However, one factor which I mentioned in the first part of the talk is that Gulf of Maine is fairly shallow and it also mixes vertically fairly rigorously at least part of the year. And so it's susceptible to heat from the atmosphere. It is good at taking that up. And then also it's a restricted ocean basin and it sort of delicately poised between warm slope water coming up from the South and Labrador slope water coming from the North and is also including these shelf water inputs. And so any shift in the balance of those can have a big impact. And one hypothesis that's out there and is being investigated and has been proposed by several people is that the Gulf Stream is shifting North or at least there are portions of water, there's sort of Eddie's warm rings of water that are migrating Northward more than they used to and entering the Gulf of Maine at higher rates. And so not only are we just getting direct heating from the atmosphere, but we're also getting potentially, it's increasingly looking likely that we're getting more warm water entering the Gulf of Maine, advecting we say in oceanography from the South. So those two things together and potentially including other factors as well are really causing this area to be hypersensitive to change, global change. And I wanna share with you a little bit about paleo-oceanography because it's really vital context for understanding how we got here and where we're going. So when I'm talking about paleo-oceanography with school groups, talk about how did we get here and how does the system work on longer time scales? How, what could the future look like? We can't understand that unless we understand how the system works and the big picture, how the whole earth system works. And we can't understand how that works unless if we've only been observing it for a tiny, tiny portion of its history, its operation. So we're gonna go be detectives now and use clues that we have been left behind to try to understand what happened and what is even possible within the earth and climate system. How to travel back in time, in other words. I study mud, it's pretty much a dream come true that I get paid to play with mud. And there are different microfossils present in that mud marine sediment that accumulate through time that can be used to understand paleo climate or past climate. There are planktonic organisms that build little shells that they're floating in the water. They, you could scoop them up with a net. And I do, they're living here and recording the conditions in the upper ocean. And they're also what we call benthic species, shells that live either, or organisms that build shells that live either on or burying within the sediments as well. And so those two things combined can give us an understanding of what's going on in the upper water column and also on the seafloor. So we go out, paleo-synographers go out in ships. We take sediment cores, we pull up sediment from the seafloor and then we bring it back to laboratories and we examine it. And we sample it at discrete depths to look at, essentially look at different times and then try to piece together a history of that area of ocean. And one of the things that we can do, I mean, we can't go back in time with a time machine and stick a thermometer in the ocean. And I really wish I could, but the next best thing is using what we call a proxy. So a proxy is something we can measure now today of some material that is present that can tell us about some past ocean conditions. And I'm showing in this figure, what's called a calibration figure, a relationship between temperature of water, temperature of seawater in degrees Celsius, from cooler to warmer. And then the ratio of two different elements in these shells, these microfossil shells. So the magnesium to calcium ratio in these fossils from the sea floor, that ratio in millimoles per mole changes predictably with temperature. So in other words, we can extract or uncover ancient fossils, measure their composition, their chemical composition and then have a clue as to what the temperature used to be like thousands or even millions of years ago. I think it's a pretty amazing tool. So this is just one example of many things that we can measure to learn about the past ocean. So we, using marine sediment cores, this is a core that was collected several years ago by Dan Belknap and others at the University of Maine and they did some of the first pioneering efforts of understanding what was going on in the Gulf of Maine. They went out and collected sediment cores from Jordan Basin and Georgia Basin and way offshore to try to come back and then figure out what kind of properties have changed through time. And I love this image because it shows very dramatically just by eye, you can see that the bottom, these sections of core are red and then they change to gray and clearly something happened. And there are lots of other more subtle clues that we can look at in these cores to learn even, to learn more, to learn what happened. In 2021, I led a research cruise. It was the first one that I was a chief scientist on, which was exciting and also intimidating, but it all went really well. We took the research vessel endeavor out into the Gulf of Maine. We left from Rhode Island and we made this huge circuit around the Gulf of Maine, several different sites. And we did many things at these different sites. The whole point of the cruise was that we wanted to figure out how conditions in the Gulf of Maine have changed through time, way beyond the reach of modern observations. So people have been sticking thermometers into the Gulf of Maine for about a hundred years, give or take. And we wanted to understand on thousands of years, many thousands of years, how conditions have evolved, what kind of natural processes affect conditions here as sort of a baseline or a way of gaining new insight into what's happening here. So to do that, we took the ship and collected long sediment cores and short sediment cores and water and plankton and lots of different material to make this all possible. And we visited several different locations and then came home with literally a ton of mud that we loaded into a humane van that just barely made it home because it was so full. And this kind of work requires a major effort on a huge team of people. These are some of the people. This is the science party who are actually on the ship, not shown are the crew, the ship's crew, and then the many, many people involved who helped plan and fund and then also process material afterwards. But it takes a lot of effort to go out and do this kind of work. And so it's very much still ongoing. But once we got out there, we were looking for records, long-term records of material that could tell us about the history of the Gulf of Maine. And so we were sending sound waves down to the sea floor and they were bouncing back at us and there were sensors that were detecting them and then sort of drawing a picture of what was underneath us. And there were layers of sediment that had different properties. And so that affected the way that the sound waves were bouncing back and that shows up visually on this diagram. And sort of like layers of cake, they can tell you about, they were made of different materials and ultimately contain different clues to what the Gulf of Maine was like in the past. And there were many different kinds of sediment that we brought back, but sediment, these short cores, this is called a multicore. It looks kind of like a metal tarantula. We sent this down to the sea floor and then we brought back surface sediments. This helps us in kind of ground truthing our proxies or these geochemical tools that we use to reconstruct past temperatures and other properties by saying, okay, we know the modern ocean conditions because we can stick a thermometer in that and measure all the other properties. And then we know that the, or we can double check and by radiocarbon dating that the surface sediments, the very topmost sediments are modern. We're deposited under modern conditions and we can compare, we can check that our proxies or our geochemical relationships are working or giving us what we expect. So that's why we went for sort of shallow sediments. And then we also deployed much longer coring devices over 10 meters long, this one. And those were designed, these types of sediment cores are designed to go back as far in time as we can. So to punch through layers and layers and layers of mud to get to the oldest material that we can reach. And in this case on this cruise, we brought back some mud that was 19,000 years old, which was very, which was exciting. I mean, in terms of geologic history, it's not very old, but the Gulf of Maine it is because when the ice was filling up the Gulf of Maine, there was not a lot of deposition going on. And so most deposition was happening after the ice left. And this is pretty much when we think the Gulf of Maine 19,000 years ago was about the timing of when the Gulf of Maine started to open up. The ice was receding and material was starting to build up. So we basically went back as far as we could, which was very exciting. This is, I'm gonna show a very, very short video clip and I'm keeping an eye on the time. I wanna make sure we absolutely have time for Q&A, but I'm gonna show a very, very short video clip of one of these corn devices going down. We put a GoPro on it. And we had- Sure shark? Yeah. Whoa. The blue shark. Yeah, we had one of the locals checking us out. Holy cow. Pretty neat. Yeah, I work with single celled organisms that make microfossils. So I don't get to show images or videos of charismatic animals very often. So this is super exciting for us. Once we got the mud back on deck, we sliced it and sub-sampled it, put it into containers. You can see, you can even see by eye, these little dots are tiny, tiny microfossils. And those are what we ultimately will sieve out of the cores and then analyze. Here are some of my students on that cruise. We've split open a core and we're looking at what kind of goodies we've brought back up from the sea floor. We're taking little samples out and then those we have been in the couple of years since we've been just working, working, working in the lab. One of the things that we do is once we get the specimens out, once we get the microfossils out and clean them off, we dissolve them and run them through a mass spectrometer. And this is a device that allows us to figure out the chemical composition of the shells. So we figure out things like that magnesium to calcium ratio that I mentioned earlier, lots of other properties we can measure with this. And just one quick example of the kinds of records that are possible by doing this kind of paleoceanographic work. I'm showing here, this is a photo of Maddie Payton. Oh, and I forgot to put her name on here, but she was a UMain undergraduate student. She just graduated this spring and she's going into the Navy. She just got her commission. But she did a senior project with me studying this core on the Scotian slope. And what she did was she wanted to monitor the properties of water that are entering the Gulf of Maine from the Northeast. And so this core is strategically located right about to be bathed by Labrador slope water that is flowing along this contour, whoops, flowing along this contour and entering the Gulf of Maine. And so she measured, she first extracted lots of micro fossils. You see she's next to a microscope here. She spent a ton of time on the microscope with a tiny detail paintbrush like pulling micro fossils, identifying them and isolating them for analysis. And then ultimately she generated this record of oxygen isotope composition, which I didn't get into because I didn't have as much time as I would like to tell you all about paleoceanography. But essentially this property varies with temperature and as well as the oxygen isotope composition of seawater. And what Maddie found was that over time, so zero being the present on this X-axis and going back farther in time to the right in calibrated kilo years or thousands of years before present so that it extends to 20,000 years ago. That's the far right side of the graph from 20,000 years to the present. She saw some initial warming, which is probably the end of the ice age there where it was the Laurentide ice sheet was melting back. And then she saw sort of a bumpy cooling throughout the remainder of that record. And this is just preliminary work. It was done by an undergrad in the course of one year, which is seriously impressive. And I've got a PhD student working on this and we'll get a lot more data points here. But the overall trend is telling us that the Gulf of Maine, by and large, over the last several thousand years has been cooling. And these are Maddie's data from the Scotian slope, but they're also previously published data from the Jordan Basin, which is in the Gulf of Maine and the Labrador Sea, which is just around the corner. And those also show overall, they're bumpy because there's natural variability but there's an overall cooling through time. So the recent history is telling us the Gulf of Maine was on a cooling trend before the industrial era, which is essentially when the modern warming started. All right, I'm gonna wrap up here. I've got just a couple more things to say. For example, there's been a lot of exciting work on understanding this in recent years. And one of my colleagues, Nina Whitney, I've been to see with her before and she's been working on the Gulf of Maine for quite a while now. She and her colleagues did a really interesting study, not studying microfossils or forminifera like I do, but studying clam shells, which put on annual layers. She pieced together a record that shows that the modern rapid 20th century warming has reversed 900 year cooling in the Gulf of Maine. So for the previous almost 1,000 years, the Gulf of Maine had been cooling. And then in the last, in recent history, that trend has reversed and we've been on a warming trend. So that is important context in terms of understanding what's going on now is it natural, is it not natural? It's a departure we now know from what was happening before. All right, some take-home messages and just a brief word about future research that's ongoing. Again, I wanna emphasize that heat from global warming is really going into the ocean at the moment. It's the ocean is absorbing an enormous majority of that heat budget, that imbalance. And unless we change the equation, that is gonna continue, it's gonna keep going. And so it's really up to us to change the amount of heat trapping gases that are in the atmosphere. We know we can do it. We know that we're already doing it and there are noticeable impacts. So that's all, I actually feel really encouraged by what I've learned in recent years about what's possible when people really get together and make not just both make personal choices and also make policy changes, those both can make a huge impact. And so I think it's well within our power to bend this curve here. We just need to do it now. I mean, as Nick mentioned in the very beginning. And so like as I mentioned too in the part two of the talk, heat from the atmosphere and heat from the oceans are both affecting us here in the Gulf of Maine. This is a sensitive area because it's shallow and because it flushes quickly and because of where it is located in the broader circulation scheme of the Atlantic Ocean. And it matters. So the Gulf Stream position matters and the Gulf Stream is affected by the westerly wind position and the westerly wind position or the jet is affected by heat gradients in the atmosphere. And those are being driven by greenhouse gases that are trapping heat in the troposphere and cooling the stratosphere. And that's just spinning them up, moving them forward, both in the Northern Hemisphere and the Southern Hemisphere and the impacts are global. And then coming years, my students and I and our colleagues will be continuing to work on these materials that we brought back from our 2001 cruise. We're gonna be developing long-term climate histories from this region. It takes a long time, it's a lot of work. So it's, you know, stay tuned and we're gonna assess the modern trends that we're observing and feeling today in the context of this, these broader, longer ocean histories. I wanna acknowledge, I hope my UMaine team in particular, my two grad students, they have two PhD students and I couldn't have done any of this without them, really. Madeleine Woods has been crucial to this entire effort, was my right hand when we were out at sea and Cassie Sturpey has also been just a rock in terms of, you know, helping mentor the undergraduate students and training everyone and it's a team effort, it's a huge team effort. And my super undergrads, not even all of whom are listed here, this kind of work takes a village. And on top of that, it takes a village and also takes money. And it's harder and harder to find funding for it now. But we were fortunate to receive funding for this particular paleogeographic project from the National Science Foundation, Marine Geology and Geophysics Program from their career program and also from UMaine Center for Undergraduate Research. And I really, really have to wrap up now. So if you wanna get in touch with me, I'd be more than happy to answer your emails as soon as I'm able, my contact is listed here, Catherine.a.allin at main.edu. If you're a social media type, my students run an Instagram account called UMaine Paleo and they're having a lot of fun with that. So if you wanna keep track of our activities, feel free to check us out there. And with that, I'm absolutely delighted to have had this time with you and I'd welcome your questions and feedback. Thank you. Thank you. Doctor Allen, thank you so much. That was fantastic. I have never seen such a deep dive into this Gulf. We think it's just a bunch of water out there, but there is so much more to it. And if you have questions, please put them in the Q&A. I did wanna make a note about wildlife. You know, as you saw from Dr. Allen's presentation, the Gulf changes a lot, has changed in the thousands of years prior to us a lot and the wildlife has changed too. I actually recently spoke with Dr. Allen's colleague, Dr. Jacqueline Gill, about some wildlife that used to live in what is now Maine during different periods of glaciation. That includes mammoths and polar bears and things that we do not think of as Maine wildlife now. And I mention that because the wildlife we do think of as being Gulf wildlife now, there's nothing keeping it here, right? As the climate changes, those wildlife too will move on. So the puffins that we love in the Gulf, they are dependent on certain food sources, like sand lands and other fish that may not exist, that may not be able to live in a Gulf that's a different temperature. We already are seeing fish and creatures, black sea bass, smooth mud crab, creatures that are traditionally thought of as more southern species working their way into the Gulf. So, you know, we need to work to protect this because it'll change, you know, the animals will move on if we don't. Dr. Allen, I wanted to ask you a question about your micro fossils. Can you talk a little bit about what those are or were and sort of how they fossilized? Absolutely, yes. I'd be glad to. Let me see. Let me pull up an image so we can... Okay, I did also, while you're pulling the image, I also want to commend you on the credit that you gave to other researchers during your presentation. Everyone had a site and a photo of the person. I've never seen such a thorough job. What a good colleague you are. Oh, well, thank you. It's oceanographic research. I mean, that's what we have. It's the right thing to do. It's, you know, it takes a lot of effort by a lot of people and I, my own work is really built on foundational work by a lot of other people and I just, it's very exciting to be here at this time because there's just so much else going on. It's a really happening time. Okay, wait, let me go back and actually share my screen with you. Zoom, zoom, zoom. There we go. Share screen. Okay. In this image, I am showing a couple of different things. There are, so for Manifera, these are single celled organisms which is incredible to me because the little tiny shells they make look like little cathedrals. I mean, they're so complex and they are really incredible and they inhabit lots of different depths and habitats within the ocean. As I mentioned, there are planktonic ones that float in the upper water column and those add carbonate chambers that accommodate the growing cell, you know, the growing cytoplasm as it keeps becoming larger. They eat other organisms. When I was a grad student, one of my major activities was, one of my major projects was growing them in a lab. So we would go out and scuba dive and catch them and bring them back to the lab and grow them in little jars of seawater. And we fed them, you know, baby brine shrimp, you know, artemia. That- Sea monkeys. Yes, exactly. You can buy them in the pet store. Yeah. We did. To feed to these guys. So they can, you know, these little single celled organisms, these protists can eat shrimp. I mean, if they were our size, they would be horrifying. They would be terrifying. So they are keep, they eat other organisms within the planktonic ones in the upper water column and the benthic ones that live on the seafloor. They eat a lot of detritus as well. They're kind of garbage eaters, some of them, but they eat nothing, very little is wasted in the ocean. So they're part of that. They're part of that system, but they build and you can see, they add these chambers as I mentioned, as they're growing and the calcium carbonate, which is, you know, basically what most shells are made of that you would pick up on the beach. These are made of very similar material. It's just very, it's just much smaller. They're about the size of a grain of sand, typically. Cool. Wow. And they lock into that shell material, isotopic and elemental compositional data that correlate with things like temperature and salinity and pH and nutrient levels and all these different things that we are interested in. And so they're this little archive, this little treasure trove of information that has to be decoded. We have to figure out what it means, but it's preserved. So they think to the seafloor and they're buried or many of them are there. Some of them get eaten or dissolved or, you know, not everybody makes it to the seafloor, but the ones that do get buried and they reside there in this giant library of mud that we can go and sample later. Fantastic. So we are past the hour. We have time for one question. I think this is a good one from Karen. What are the projections for the continued warming of the Gulf? Well, there are multiple projections. All of them are on a warming trend. And I really think that a lot of it is uncertain because of the uncertainty regarding what humans are going to do in terms of what the, there are different scenarios that you might be familiar with, these different emission scenarios, these future projections that are sort of there's a worst case scenario. There's a business as usual scenario. There's a, you know, there's a sort of like, you know, we'll really, really do something about its scenario. And what ends up happening really depends on which path we take. And so that's the major uncertainty is really people in this equation. So I am, and I'm not a climate modeler or an ocean modeler. So I would also defer to colleagues who really specialize in that. But I think it's up to us. Thank you very much. I wanna thank you, Dr. Allen, for joining us today. This was fantastic. For folks still watching, we'll put the video up shortly. If you wanna learn more about wildlife in the Gulf of Maine, climate in the Gulf of Maine, offshore wind in the Gulf of Maine, please come to the Maine Audubon website, Maineaudubon.org slash Osw to learn more about what we've learned about the potential impacts to wildlife from offshore wind and how we can avoid them. Thank you so much. Have a great rest of your week, Dr. Allen. Thanks for joining. And go yachtsmen or navigators, whatever it is now. FHS. Take care. So much. Have a good week. Thank you.