 Welcome back, our next presenter up comes to us from the University of Puerto Rico at my West, Stephanie Ortiz Rosario. Her title of her presentation is Environmental Moisture Influence on African Mesoscale Convective Systems. Thank you so much. Hello, I'm Stephanie Ortiz Rosario. I'm an undergraduate student from the University of Puerto Rico at my West. And today I'm excited to be sharing more about how moisture can influence mesoscale convective systems, specifically over the African region. And this work is actually in collaboration with my mentors, Katie Nunez-Ocasio, Zachary Moon, and Chris Davis from the Mesoscale and Microscale Meteorology Lab. So first, I would like to get you all more familiar with the Mesoscale Convective Systems, or MCSs. Joe explained a little bit about it in his presentation. But technically these, we can describe them as the largest convective storms. And think of these as a group of clouds that have a very large area. And this area has to be at least 100 kilometers, horizontally, and within this area there also has to be precipitation. But this precipitation, something curious about it, is that it's not equal across the entire area. And if you see this figure to your right, this is a radar image on how a typical MCS looks like. And if you see in the front of the system, more red regions, this indicates more intense rainfall from the convective region, and then more in the brown, orangey areas, this is more associated with lighter rain from the stratosphere region. And systems like these actually cause a large portion of rainfall, not only here in the mid-latitudes, we can see these over Colorado, but also in the tropics. And this actually leads me to the African-Messus Co-convective Systems in which, in West Africa, the rainfall is mainly associated with these systems. And in the figures to your right, is there is basically a schematic on the weather phenomenon that can influence the weather and climate over the African region. And they can also influence the Messus Co-convective Systems that form. And for the sake of this, of the focus of this project, I'm gonna be emphasizing too, and they're listed, the first one is the African-Easterly Jet. And you can think of this as a belt of high-speed winds over the region. And I also wanna emphasize the West African Monsoon, or WAM, and this is actually seen in the figure above, where it says the ocean co-tongue. These are actually Southwestern winds that they transport water vapor into the African region. And this is situated over the summer in the African region. And why should we care about African-Messus Co-convective Systems? One of the reasons, which actually is close to home, because on Puerto Rico, we get a lot of tropical cyclones, it is that these systems are a key role in the tropical cycle genesis of the African-Easterly waves. But also, because compared to the weather in the mainland, the knowledge about convection in the tropics is more limited, especially because the data is scarce, so we don't have access to a lot of instrumentation across the area. And it can even give us insights about climate change effects related to the water vapor. And MCS have been studied in different ways, but I'm gonna emphasize one that actually helps us answer our research question, which is how Messus Co-convective Systems are modulated, how they change when we alter the moisture. And the method we used is through modeling, especially specifically through the model for prediction across scales, or MPaths from NCARM. And in here, the most important feature about these simulations is that they can let us alter the moisture at different levels of the atmosphere. Specifically moisture, the variable here is the relative humidity. So in general sense, we have three different experiments, so we have one in control, no alterations in moisture. Then we have a moist experiment where the moisture was increased across the atmosphere, 20%, and then we have the dry region where the relative humidity was, or moisture was decreased 50%. And the domain, which is over the African region and the Eastern Atlantic, specifically over the center, it has a very high resolution, so it let us capture the formation of clouds more in detail. And this data is situated over September of 2006, and it runs for a period of five days. Now that we have these three experiments, first we want to see how clouds form, or MCSS, but in a general sense, we want to observe the clouds. And I did this by tracking MCSS by eye or subjectively, so you can see the drawing where I was following the clouds that formed in the control environment, in the moist environment, and then in the dry environment. And one fun fact about this is that if you noticed in the dry environment, you don't see a cloud formation until later during the simulation. And it's actually through MPASS. But because we want to obtain more specific details about how many MCSS formed, like how long did they last through the three simulations, we used an automated tracking algorithm, or this is more of an objective tracker, and this tracker is called the Tracking Algorithm for Mesoscopic Infected Systems, which was actually developed by two of my mentors. And this algorithm is based in three main steps. So first we want to identify these clouds that formed. We want to see if they can be potential candidates to become MCSS. And we do this through the cloud top temperature, like the brightness temperature, so basically how bright the clouds are. And after we identify these potential MCSS, we want to follow their path. So that is why we use tracking as specifically the area overlapping technique. And lastly, we have the classification, which once we have these clouds, we have to say, oh, are they organized? Are they disorganized? Did they last more? And this is why they are in the disorganized and organized main categories. And then we have from the ones that are more disorganized and last less, like the disorganized short-lived, and then the ones that are bigger and tend to last more like the mesoscopic invective complex. But now we want to see how the African environment looked during these three simulations. And first, I want to start off with one of the environmental atmospheric phenomena that I talked in my second slide, which is the African Eastern Legion. And we have these plots actually represent the winds at 600 ectopascals, which is roughly close a little bit more than four kilometers in altitude. And the counters actually mean the wind speed. And you can see that between the control and moist, this belt of high-speed winds actually shifts a little bit to the north and in the moist environment compared to the control. And they also can, you can see some darker shades of the counter, which means higher wind speed. However, now if we compare it to the dry environment, we can see that this belt kind of ripped apart, and especially over the south compared to the control environment. Now we want to examine our second atmospheric phenomena over the, that can affect cloud formation over the African region. And this was the West African monsoon. And in here we can, this is lower closer to the surface in terms of altitude. And the green counters basically show the amount of water vapor available in the atmosphere. And the vectors actually mean the wind speed. And the southwestern is the signal of the African, of the West African monsoon. And when you compare the moist with the control environment, we can see that especially over the 10 and 15 north, there is a darker shade of green. So it means more water vapor in this environment, and that also an indicator that the West African monsoon intensified. Now, if we look into the dry region, we can see that there is a lighter shade of green, which means that there was less water vapor in the dry compared to the control environment. So we can say the West African monsoon, we can't in this environment. And to get a general sense, before we dive into the statistics of the MCF, it's like how many they formed across all simulations. I wanted to show you all the mean precipitation rate across the entire simulation. So basically these plots show how much rain felt felt during like five hour. And if we take a look when you compare moist into control, we can see more darker colors, specifically over the 10 and 15 north in the moist compared to the control. And this can actually be related with the West African monsoon moisture. And then in the dry, we can see that we barely see any precipitation over here. So for the summary into this part, we know that between the West African monsoon and the African easterly yet, they both are enhanced in some way in the moist environment compared to the control. But we saw a greater difference in the West African monsoon of the moist environment compared to the control one. So we can say about this that the mean precipitation rate can be more associated with the West African monsoon specifically because it can with the moisture availability, it can affect those clouds can intake that and form. Now, into seeing like how many MCS is formed, like did the moist form MC more MCS is or the control, we will find out. And in here, I show you all a box, a bar plot, which shows the four categories that TAMS uses to identify the MCS's. So from the disorganized, the organized systems. And across all the categories, we see that there are more number of African MCS's in the moist, I'm sorry, in the control environment. But we wanted to look at other variables, such as like how long these MCS's lasts. And if we take a look into the, this is a box plot, which shows I'm gonna focus in the medium, which shows like the average duration of these MCS's and also the whiskers or the lines over the moist and the control environment, which shows like the extremes of these values. And it is very notable that for the organized MCS's, the dry actually, these MCS's that forms lasted less. And well, and in control and moist, they lasted roughly the same, comparing it to the median. But now if we see the extreme values or the extreme of the whiskers, we see that the moist can have more extreme durations compared to the control. And lastly to show you, I want to emphasize here in this scatter plot, the MCS area. And this is for the organized message African MCS's. And if we take a look into the control compared to the moist, we can see that the slope of the moist actually is higher. So it shows that for the same amount of duration of these MCS's, the moist ones tend to have greater areas. And then in the dry, these tend to have less area, a smaller area than in the control. So now for the summary, the main takeaways is that, first of all, the environmental moisture does not equal that more African MCS's. But because we saw this that we had more number of MCS's in the control compared to the moist. But we did see that more extreme long lasting, more extreme long lasting MCS's in the moist environment. And because of the moist difference in here, we can see between the moist and the control with the West African monsoon, we can see that these longer, last day and higher areas can be associated with the monsoon of moisture. But we still have one question to answer and we will need to evaluate more variables for this. And it is basically like why more MCS's is formed in the control environment instead of the moist, for example. And this is part of the future work. So we want to, this is another step that TAMS can do. We can study specific MCS's, we can like for example assign precipitation, we can track them and we can see where they situated in terms of the variables that are affecting them such as the African easterly jet or the West African monsoon. And that is everything for my presentation. I would like to thank Nessie for the opportunity to be here. Thank you so much. Hello, so we got some questions. I also wanted to remind everyone online that you could submit questions through Slido. Thanks for the great talk. Could you explain why you choose those percentages for the different runs like 20% plus in moist and 50% minus for the dry? Yeah, that is a great question. So these simulations are actually post-processed. So they basically, the reason why we chose the 20% is because like if we increased moisture more, the atmosphere was gonna be oversaturated. And this actually would provide the simulation with a, basically a less realistic feature on the convection over the region. So we couldn't increase the moisture up to 50% because we want a realistic feature of how I'm trying to look here into the percentages so that you can see them. So yeah, basically we want to obtain a more realistic feature of the atmosphere. So we increased moisture too much. The atmosphere was gonna be more saturated. Next sentence, thank you. So I have the question about the topography in Africa. Does that affect the systems? Yes, that is a great question. And they actually do. I'm gonna search the picture, the figure that shows the African region. So in Africa we have many mountains and plateaus and highlands. So they do can affect how the convection forms. And I wanna show you actually the mean precipitation rates where actually it was very interesting because in the moist environment we saw increased in places where we had the mountains. So yes, you can see the increased in the precipitation over the ocean, but also if you see those like small dots of high precipitation over the land. So this is actually close to the Guinea highlands and Joss Plateau and Cameroon Mountains. So this could actually be an indicator of the topography affecting the systems. Thank you. Thanks for a really great presentation. I wanted to ask you, I don't know if you can, but if you could expand on the 20, 50% moisture increase decrease. Is this, I know you said that you wanted, you were sort of had the boundary condition of still wanting a realistic simulation, but does this relate to anything else in the climate system? Any variability that might be close to that? Or do you expect maybe 20% increase in moisture due to climate change? Or is there any other like physical reason that you could relate these percentages to? That is, thank you for the question. So what we can actually, yes, we can relate this in terms of the climate change because as we know, there is gonna be a water vapor increase. So I'm not sure of how much, but this could be a way to observe this. So I would like, I mean, it would be interesting to look more into that. Thank you so much, Stephanie, for this presentation. Do you mind me asking, why did you specifically choose that period of time in September? Is that most commonly when these MCSs are occurring or are they kind of common throughout the year? Do you mind expanding on that a bit? So one of the, during the summer, so one of the factors that can affect cloud formation like the African Easter Leisure, it becomes stronger during this period of time. And also the West African monsoon gets stronger during this time. So we have these clouds forming and this is very interesting because in 2006, we had the formation of Hurricane Eileen. So it was actually very interesting to look how the clouds around the system look like. Wonderful work, Stephanie. Thank you so much. Thank you.