 After that very eloquent, you know, piece from Manu, I'm glad that I had the wisdom or foresight to go to a completely different problem and not repeat what Matt and Manu would be already saying. I figured that's what they would be talking about. So I chose to talk about something different basically because I knew who was going to talk before me. So I thought I would take a slightly different land and talk about resilience produced provided by groundwater and mountain watersheds which might offset some of the concerns that are coming up because of climate change. I'm going to talk a little bit about, you know, the Colorado basin and then about some of the Himalayan basins just to contrast. So in the upper Colorado basin, for example, some recent work, you know, which is based on conductivity, mass balance type analyses, suggested about, I mean more than half the stream flow actually comes from a base flow derived source. Although 80% of that then gets lost to ET and diversions before it goes to the lower basin. But the fact is that a lot of this water is coming through a groundwater flow pathway into the stream and manifested stream flow. And in the two graphs that are shown there, it shows that the base flow yield is higher at higher elevations. But as you come to the lower reaches, the higher order streams, you actually find that the fraction of the annual stream flow that is provided by base flow is significantly higher. And that 56% number is sort of like an average. When you come to the lower elevations, it can be as much as 60-65%. So there is some measure of resilience there because groundwater we think of as a store that has a little more delay in delivering hydrologic inputs to streams and can sustain late season flows. That being said, in much of the US, the climate change scenarios provide a grim portrayal of hydrologic inputs. And we cannot assume that this is an entirely optimistic set of circumstances. At the smaller scales, which people are starting to study now, where on the right frame, the East River study, the DOE SFA, which is a very nicely funded piece of work, and several other similar works in the Oregon Cascades and in the Sierras, there's a lot more appreciation now of the role of deep groundwater in the hydrologic budgets and the water budgets of these fairly water stress systems that have not been considered in the previous work, as Manu pointed out that from a hydroclimatic perspective, typically look more at shallower depths. But when you look at the role of deep groundwater, for example, at this East River study site, when you take the annual snowmelt pulse and ask, well, how deep is that producing a groundwater circulation? That's in the range of about 80 meters. So that is fairly deep compared to what typical land surface models are able to capture. And a lot of climate change projections, the coupled models are beginning to, and I'm sure Laura will talk a little bit more about role of deep groundwater. And in the Southwest and US, there is some evidence that suggests that the reduced recharge will have significant influence on groundwater availability and even in these mountain systems. And in some unusual instances, you actually get some very strange water quality consequences of declining water tables. For example, in mineralized watersheds, you get higher metal loads in streams, very, very strong 30 year trends that are putting some of these metals concentrations in streams, in small mountain streams to be above aquatic life standards. Very little is known about some of the more remote areas in the Himalayas, which are from a geopolitical perspective fairly sensitive areas. The recent Charis project that was a fairly comprehensive study of water budgets in the Himalayan basins, contrary to a lot of previous notions, glacier loss is not a big contributor to the water budgets in these systems. It's snowmelt and precip. And if you come to a basin like the Ganges, it's actually monsoon rain that controls most of the action and not even, I mean, it's normal to some extent, but monsoon rain. And a combination of the monsoon and rainfall forcing even that actually is delivered to the stream when we look at the right frame via groundwater flow pathways. That's a very nice, it's a data set, it's real data, it's not a modeled data. This, the color scale there is the time blue colors are early in the year and red colors are later in the year. This anti-clockwise history's loop basically says that, look at the one-to-one line also, in most of the year, you actually have stream flows that exceed precipitation inputs. That signifies a delay that is coming because of a groundwater pathway. Two-thirds of the annual discharge in the upper Ganges basin actually is coming from a groundwater pathway that implies a delay of about two months. And there is a certain level of resilience there. What's really kind of intriguing is that climate change impact projections in the Himalayan basins suggest that you're going to get an increase in precip. I don't know how, you know, I'm not an expert in the sense of how much to believe these projections. For example, in some parts of the upper Ganges basin, it's projected that you'll have a 30% increase in stream flow because of climate change induced precip increase. And in the Karakoram ranges in RCP 8.5 even 80%. Uncertainty surrounding these numbers, I don't know, but, you know, it's very intriguing to think about if you were going to send troops there, you have to drill a well and you have all the water that you need from some of these mountain groundwater systems. So that might be, you know, something that is opposite to the more plains type groundwater systems where depletion is really more of a concern. And of course, you know, to answer these questions more reliably, how do you go about characterizing mountain groundwater systems? And maybe there are some airborne and remote sensing solutions there. So stop there.