The Earth From Space: Josh Willis

Curator Jay Belloli interviews Josh Willis, Oceanographer, NASA, JPL, Caltech.

Jay Belloli: Josh, how did you become interested in studying oceanography?
Josh Willis: Well I failed out of physics. I was planning to get a Ph.D. in physics at the University of California San Diego, and physics really didn’t agree with me. And I didn’t find anything that I wanted to study passionately. When they booted me out, I started to look for something to do. Just down the hill from UCSD was the Scripps Institute of Oceanography, and people there were studying things about the ocean that I thought were really exciting. And so I started to study the physics of the oceans, and specifically the physics of climate change and how the oceans are affecting global warming and impacting people. I found something I was passionate about and I’ve been studying it ever since.

JB: Please tell me about the research you and your group are doing about the ocean’s role in ice loss in Greenland?
JW: It’s a focus for me right now. We’ve had a five-year long mission to study the melting of the ice on Greenland by the ocean; it’s been extended for an extra year. It’s called Oceans Melting Greenland or OMG for short. This mission is designed to fly airplanes around Greenland and measure how much the oceans are eating away at Greenland’s ice from the edge. We do that by dropping sensors in the ocean around Greenland to see how warm the water is and how salty. We also fly an airplane to measure how much the ice is retreating from the edges. And by comparing these two things, year by year, we get a sense of how important the ocean temperature changes are, and how much ice is lost from Greenland’s glaciers.

JB : What I'm intuiting here is that, because of the ice loss, the ocean close to Greenland is not as salty as it might be at other locations.
JW: The ice loss does affect the salinity there. But it’s surprising. The ocean water is upside down there. You normally think of warmer water near the surface. In Greenland there is a layer of warm water underneath, and a layer of cold water near the surface. The warm water around Greenland comes from the Atlantic Ocean, and the cold water comes from the Arctic. You wind up with a layer of cold fresh water over a layer of warm salty water.  The warm, salty water from the Atlantic melts the Greenland ice from below. When the Atlantic water melts the ice, the cold fresh water on top becomes a little fresher. And the warm Atlantic water keeps reaching in there and melting the glaciers from below.

JB: That’s fascinating. Technically how do you do this research? How do satellites fit in to what you and your team are doing by dropping the probes into the ocean and flying over the Greenland ice? Are you using satellite data? 
JW: Oh absolutely. Satellites tell us things like how much of the entire ice sheet is being lost. There was a relatively new satellite launched during the middle of our mission called ICESat-2, and that is actually measuring the ice height everywhere and how it changes over time. So we do use satellite data. But they don't have satellite data from space that measures the water temperature below the surface. You really have to monitor the deep-water temperature with a thermometer, and that’s again why we are flying these airplanes around and measure the temperature directly.

JB: What information has resulted so far from the research that you and your group are doing?
JW: Everywhere we look we find that the oceans are playing a bigger role in ice loss than we thought. Some of the early work we did in OMG is just mapping the sea floor, which were not well mapped prior to our mission. There were big gaps in our knowledge of where the deep parts were. We found that the deep channels were carved into the continental shelf by ancient glaciers. They allow the warm water to creep up next to the glaciers in a number of cases, giving them better access to the warm water than we thought. In the first year of our survey, we also discovered that the melting of Greenland’s largest glacier, Jakobshavn Glacier, actually slowed down and grew for the first time in twenty years. This was really surprising because we expected that glacier to continue to retreat until it was gone. The reason for this change is that cold water crept up on the shelf as part of a natural cycle, and bathed that glacier in cooler than normal water. 

JB: What we're really finding is that the ocean is playing a huge role in these glaciers’ retreat. And we’re going to have to account for that if we want to predict sea level rise in the future. It's my understanding that the vast majority of increase in carbon dioxide goes into the oceans rather than into the atmosphere because the oceans covers about 70% of the planet.
JW: About a third of the carbon dioxide that we put in the air goes into the oceans. But it’s still a huge amount. And that does several things. One, it makes the oceans more acidic. But it also means that, even if we started drawing down the carbon dioxide the atmosphere today by some magical means, that extra carbon dioxide in the oceans would still affect us significantly. So the oceans are really one of the most important factors in how climate change plays out. They absorb over 90% of greenhouse gasses, and also absorb about a third of the carbon dioxide. The oceans are really the big player when we think about climate change and global warming.

JB: That is really interesting and important. In a related question that comes from my research for the exhibition, I think people need to understand what is going on in terms of rising sea level. My question is, what is going on in Antarctica in terms of ice loss?
JW: Yes, absolutely. Greenland is losing ice because of global warming, but also so is Antarctica. We know this because of two of our satellites, GRACE and GRACE-FO. These missions are literally weighing the continents; they tell us how much each of them weighs. Both Greenland and Antarctica are losing ice. And they are losing ice really quickly, and contributing a whole lot to sea level rise. The processes in Greenland and Antarctica are a little different though. Every summer the surface of Greenland melts. Not all of it but a lot of it. By contrast, in Antarctica not that much of it gets above freezing every year. Some parts do, but not the majority of it. So a lot of the melting in Antarctica is being done by the ocean, even more than in Greenland. So are the oceans melting Greenland, yes. And they are melting Antarctica even faster. 

JB: I did not know that. Some of images I have of Antarctica are shocking; there’s no other way to say it.
JW: One of the things that surprised me so much when I started doing this work was flying over Greenland and getting a sense of just how big the ice sheet was. You can get in a jet and fly for two hours and all you see is a big, white blanket of snow and ice below you. And the idea that humans are melting this thing only hits home when you realize how big it is, and how much we are changing the climate. 

JB: It is appalling. I want to ask you what research you and your group or other scientists are doing on ocean warming and sea level rise.
JW: Well there are tons of scientists, including me, that are studying ocean warming and sea level rise. With OMG were studying how Greenland is contributing to sea level rise. But we’re also looking at how much warming is expanding the water. I mentioned that the absorption of over ninety percent of the greenhouse gasses is warming the ocean. And that warming causes the water to expand. Just like metal and other materials, when water gets warmer it gets bigger. About one third of sea level rise is caused by expansion. The rest is the result of Greenland and Antarctica ice melting, as well as smaller glaciers across the planet. We’re really getting a handle on what’s causing sea level rising, and the answer is us. 

JB: What satellites are being used to measure ocean warming sea level rise? You were talking about GRACE and GRACE FOLLOW ON. Are these the satellites that are providing this information, or are there other ones as well?
JW: Yes, there are a number of other satellites. I am the Lead Scientist at NASA in charge of measuring sea level rise using the Jason missions. What these satellites do is very simple in a way. They bounce radar off the surface of the water and measure how long that radar takes to hit the ocean surface and come back up. Then you can tell the distance to the water very accurately. So if you know the position of the satellite as well, you will know how high the water is. Using these satellites, we’ve actually been measuring global sea level for decades. We’ve been watching the daily rising of the oceans really accurately since the early 1990s.

JB: I have one other question in terms of the research I've done: Is Jason 3 operational?
JW: I’ll run through the history of the satellites very quickly. In 1992 we launched TOPEX/Poseidon, which was the first really accurate satellite to measure sea level and global sea level rise. In the early 2000s we launched Jason 1, then Jason 2. In 2016 we launched Jason 3. It’s the one that is currently operational and it is measuring global sea level rise even as we speak.  

JB: You’ve talked about it briefly, but what about the issue of ocean acidity? Is it just the carbon dioxide or something else?
JW: The carbon dioxide is changing the acidity of the oceans. But the oceans are changing in a number of ways. They are warming of course. And that is changing the habitat for a lot of the little critters that live in the ocean and make up the ocean’s food chain. The ocean is a hugely important source of our food. But the phytoplankton at the very bottom of the food chain are the biggest producer of oxygen on the planet. They suck carbon dioxide out of the air and spit back out oxygen. The changing temperature and acidity of the ocean are impacting basic processes like these, and putting a lot of pressure on the ecosystems. At the same time we are putting additional pressure on the ocean through fishing and other pollution we are putting in the ocean. So the oceans are taking a beating right now, and it is all exacerbated by climate change. 

There have been international treaties about fishing zones, and many have been designated. The U.S. in the last decade or so has a large number of these protected zones, where no one is allowed to do any fishing or take anything out of the water. So it’s like preserving a little nest where the ecosystem can flourish. In fact this has been shown to be the best way to help protect the oceans. But of course these areas aren’t protected from the heat, or carbon dioxide, or plastic. So they are still suffering from some of the stresses that people are putting on them.

JB: Josh, I certainly know of the plastic areas in the Pacific. Are there plastic areas in the other oceans as well?
JW: Absolutely. There are probably plastics in every ocean basin. We’ve measured the ones in the Atlantic and the Pacific because we have a lot of shipping there, and a lot of research has been done there. Those regions in the mid-latitudes collect the plastic because of the way ocean circulation works. It’s a convergence zone, so the water pushes toward the middle. The plastics don't sink, so they tend to park in the middle of the convergence zone. But there are convergence zones in the Southern Hemisphere as well. And probably you could find plastics in pretty much any part of the ocean if you look hard enough. The oceans are all connected, so it’s only a matter of time that plastic will drift throughout the oceans.

JB: What does the warming of the oceans have to do with changes in precipitation? 
JW: A lot. We’ve noticed that the hydrological cycle, the cycle of water evaporating out of the ocean and falling back into the ocean or over land, is speeding up. As the atmosphere gets warmer it holds more water. So the cycle of water being evaporated out of the ocean and being spit back on land is getting faster. What that tends to mean is that wet places are getting wetter and dry places are getting drier. If you think about it, two thirds of the planet is covered by oceans. In fact a lot of the rain falls back in the oceans. The result is that the salty places in the ocean are getting saltier, and the fresh places in the oceans are getting fresher. This suggest that we are already seeing the speed up of the hydrological cycle, the water cycle. This certainly implies that rainfall and rainfall events are going to get more intense, and deserts and dry places are going to get drier. We are seeing the water cycle on steroids, and that’s what we expect in a warming world. 

JB: I’ve been aware of increased rain events in Houston, where I used to live. And of course the Gulf of Mexico is warm.
JW: Well the Gulf Stream comes out of the tropics, through the Gulf of Mexico, then goes around the southern tip of Florida and then along the East Coast of the United States. As it does, it makes that area very warm. A lot of the rain and storms that come out of the Gulf are activated by this very warm water. As that water warms up even more it gives stronger fuel to those storms. And as the air warms up more, it holds more water. So we're definitely looking at stronger precipitation events in some of the wet places, like Houston. 

JB: A question. The Gulf Stream is essential to Europe not being like an iceberg. There have been increasingly powerful rain events in the United Kingdom and some on the Continent. 
JW: We forget how important the oceans are to our climate. They cover two-thirds of the planet. All of our rainfall, or almost all of it, originates out of the oceans, so it has a dramatic effect on the climate. In Europe heat is brought into the higher latitudes by the Gulf Stream and by the Atlantic Ocean. As climate change starts to affect those currents and the ocean’s ability to move heat around, we are trying to figure out what's going to happen to the climate in Europe. If you turn off the ocean conveyor belt, the models of ocean circulation patterns point to Europe becoming colder, especially in the wintertime. But the models of global warming predict that, even if the Gulf Stream and Atlantic don’t warm Europe, global warming is still going to be the dominant effect.  So you would still see warming in Europe. But the warming might be tempered by the change in the currents and their ability to rearrange heat around the planet.

JB: Josh, there are obviously a number of currents besides the Gulf Stream. All of these currents could change, given what you're implying.
JW: Absolutely. And we’re beginning to see changes in what oceanographers call the large-scale circulations throughout the oceans, the Gulf Stream, the gyres we talked about before where all the trash collects, are all part this large-scale circulation. When the climate changes, these parts of the ocean will change along with them. We are still trying to understand how this will affect climate. Will there be more El Niños or La Niñas? We don’t know. The ocean’s role in determining how these changes will play out is big, and we’re still studying it.

JB: I have two questions: If basically no changes are made internationally on carbon dioxide or plastic pollution, what do you think may happen to sea level rise say in the next fifty years, or ocean temperature, or ocean acidity? The countries are very slow to do anything, and the Paris Agreement is not very strong. This is not looking good from what I can gather if no changes are made. 
JW: Well, there is a certain amount of warming and sea level rise that we’re already committed to. Even if we stop putting carbon dioxide in the atmosphere today, the planet would continue to warm for a long time and sea level would continue to rise for a long time – like a thousand years in terms of sea level. So we are due for more warming. The question is, how much do we want to tolerate? If we reduce our carbon consumption and reduce the amount of carbon dioxide we are putting in the atmosphere, we can still stave off the worst effects of the warming. But we are still not sure about how much increased carbon dioxide and sea level rise there will be. It could be a foot or two by the end of this century, or it could be up to six feet or even ten feet by the end of the century, which would be devastating. If that’s what we’re looking at, we already should be preparing cities to move or protect themselves from massive sea level rise. So we’re looking at an uncertain future in a lot of ways. And that uncertainty has to do with potential impacts. 

JB: I have two final questions. What can the average person do all regarding massive ice loss, sea level rise, ocean warming, and the growing acidity there?
Josh Willis: Well I failed out of physics. I was planning to get a Ph.D. in physics at the University of California San Diego, and physics really didn’t agree with me. And I didn’t find anything that I wanted to study passionately. When they booted me out, I started to look for something to do. Just down the hill from UCSD was the Scripps Institute of Oceanography, and people there were studying things about the ocean that I thought were really exciting. And so I started to study the physics of the oceans, and specifically the physics of climate change and how the oceans are affecting global warming and impacting people. I found something I was passionate about and I’ve been studying it ever since.

JB: Please tell me about the research you and your group are doing about the ocean’s role in ice loss in Greenland?
JW: It’s a focus for me right now. We’ve had a five-year long mission to study the melting of the ice on Greenland by the ocean; it’s been extended for an extra year. It’s called Oceans Melting Greenland or OMG for short. This mission is designed to fly airplanes around Greenland and measure how much the oceans are eating away at Greenland’s ice from the edge. We do that by dropping sensors in the ocean around Greenland to see how warm the water is and how salty. We also fly an airplane to measure how much the ice is retreating from the edges. And by comparing these two things, year by year, we get a sense of how important the ocean temperature changes are, and how much ice is lost from Greenland’s glaciers.

JB : What I'm intuiting here is that, because of the ice loss, the ocean close to Greenland is not as salty as it might be at other locations.
JW: The ice loss does affect the salinity there. But it’s surprising. The ocean water is upside down there. You normally think of warmer water near the surface. In Greenland there is a layer of warm water underneath, and a layer of cold water near the surface. The warm water around Greenland comes from the Atlantic Ocean, and the cold water comes from the Arctic. You wind up with a layer of cold fresh water over a layer of warm salty water.  The warm, salty water from the Atlantic melts the Greenland ice from below. When the Atlantic water melts the ice, the cold fresh water on top becomes a little fresher. And the warm Atlantic water keeps reaching in there and melting the glaciers from below.

JB: That’s fascinating. Technically how do you do this research? How do satellites fit in to what you and your team are doing by dropping the probes into the ocean and flying over the Greenland ice? Are you using satellite data? 
JW: Oh absolutely. Satellites tell us things like how much of the entire ice sheet is being lost. There was a relatively new satellite launched during the middle of our mission called ICESat-2, and that is actually measuring the ice height everywhere and how it changes over time. So we do use satellite data. But they don't have satellite data from space that measures the water temperature below the surface. You really have to monitor the deep-water temperature with a thermometer, and that’s again why we are flying these airplanes around and measure the temperature directly.

JB: What information has resulted so far from the research that you and your group are doing?
JW: Everywhere we look we find that the oceans are playing a bigger role in ice loss than we thought. Some of the early work we did in OMG is just mapping the sea floor, which were not well mapped prior to our mission. There were big gaps in our knowledge of where the deep parts were. We found that the deep channels were carved into the continental shelf by ancient glaciers. They allow the warm water to creep up next to the glaciers in a number of cases, giving them better access to the warm water than we thought. In the first year of our survey, we also discovered that the melting of Greenland’s largest glacier, Jakobshavn Glacier, actually slowed down and grew for the first time in twenty years. This was really surprising because we expected that glacier to continue to retreat until it was gone. The reason for this change is that cold water crept up on the shelf as part of a natural cycle, and bathed that glacier in cooler than normal water. 

JB: What we're really finding is that the ocean is playing a huge role in these glaciers’ retreat. And we’re going to have to account for that if we want to predict sea level rise in the future. It's my understanding that the vast majority of increase in carbon dioxide goes into the oceans rather than into the atmosphere because the oceans covers about 70% of the planet.

JW: About a third of the carbon dioxide that we put in the air goes into the oceans. But it’s still a huge amount. And that does several things. One, it makes the oceans more acidic. But it also means that, even if we started drawing down the carbon dioxide the atmosphere today by some magical means, that extra carbon dioxide in the oceans would still affect us significantly. So the oceans are really one of the most important factors in how climate change plays out. They absorb over 90% of greenhouse gasses, and also absorb about a third of the carbon dioxide. The oceans are really the big player when we think about climate change and global warming.

JB: That is really interesting and important. In a related question that comes from my research for the exhibition, I think people need to understand what is going on in terms of rising sea level. My question is, what is going on in Antarctica in terms of ice loss?
JW: Yes, absolutely. Greenland is losing ice because of global warming, but also so is Antarctica. We know this because of two of our satellites, GRACE and GRACE-FO. These missions are literally weighing the continents; they tell us how much each of them weighs. Both Greenland and Antarctica are losing ice. And they are losing ice really quickly, and contributing a whole lot to sea level rise. The processes in Greenland and Antarctica are a little different though. Every summer the surface of Greenland melts. Not all of it but a lot of it. By contrast, in Antarctica not that much of it gets above freezing every year. Some parts do, but not the majority of it. So a lot of the melting in Antarctica is being done by the ocean, even more than in Greenland. So are the oceans melting Greenland, yes. And they are melting Antarctica even faster. 

JB: I did not know that. Some of images I have of Antarctica are shocking; there’s no other way to say it.
JW: One of the things that surprised me so much when I started doing this work was flying over Greenland and getting a sense of just how big the ice sheet was. You can get in a jet and fly for two hours and all you see is a big, white blanket of snow and ice below you. And the idea that humans are melting this thing only hits home when you realize how big it is, and how much we are changing the climate. 

JB: It is appalling. I want to ask you what research you and your group or other scientists are doing on ocean warming and sea level rise.
JW: Well there are tons of scientists, including me, that are studying ocean warming and sea level rise. With OMG were studying how Greenland is contributing to sea level rise. But we’re also looking at how much warming is expanding the water. I mentioned that the absorption of over ninety percent of the greenhouse gasses is warming the ocean. And that warming causes the water to expand. Just like metal and other materials, when water gets warmer it gets bigger. About one third of sea level rise is caused by expansion. The rest is the result of Greenland and Antarctica ice melting, as well as smaller glaciers across the planet. We’re really getting a handle on what’s causing sea level rising, and the answer is us. 

JB: What satellites are being used to measure ocean warming sea level rise? You were talking about GRACE and GRACE FOLLOW ON. Are these the satellites that are providing this information, or are there other ones as well?
JW: Yes, there are a number of other satellites. I am the Lead Scientist at NASA in charge of measuring sea level rise using the Jason missions. What these satellites do is very simple in a way. They bounce radar off the surface of the water and measure how long that radar takes to hit the ocean surface and come back up. Then you can tell the distance to the water very accurately. So if you know the position of the satellite as well, you will know how high the water is. Using these satellites, we’ve actually been measuring global sea level for decades. We’ve been watching the daily rising of the oceans really accurately since the early 1990s.

JB: I have one other question in terms of the research I've done: Is Jason 3 operational?
JW: I’ll run through the history of the satellites very quickly. In 1992 we launched TOPEX/Poseidon, which was the first really accurate satellite to measure sea level and global sea level rise. In the early 2000s we launched Jason 1, then Jason 2. In 2016 we launched Jason 3. It’s the one that is currently operational and it is measuring global sea level rise even as we speak.  

JB: You’ve talked about it briefly, but what about the issue of ocean acidity? Is it just the carbon dioxide or something else?
JW: The carbon dioxide is changing the acidity of the oceans. But the oceans are changing in a number of ways. They are warming of course. And that is changing the habitat for a lot of the little critters that live in the ocean and make up the ocean’s food chain. The ocean is a hugely important source of our food. But the phytoplankton at the very bottom of the food chain are the biggest producer of oxygen on the planet. They suck carbon dioxide out of the air and spit back out oxygen. The changing temperature and acidity of the ocean are impacting basic processes like these, and putting a lot of pressure on the ecosystems. At the same time we are putting additional pressure on the ocean through fishing and other pollution we are putting in the ocean. So the oceans are taking a beating right now, and it is all exacerbated by climate change. 

There have been international treaties about fishing zones, and many have been designated. The U.S. in the last decade or so has a large number of these protected zones, where no one is allowed to do any fishing or take anything out of the water. So it’s like preserving a little nest where the ecosystem can flourish. In fact this has been shown to be the best way to help protect the oceans. But of course these areas aren’t protected from the heat, or carbon dioxide, or plastic. So they are still suffering from some of the stresses that people are putting on them.

JB: Josh, I certainly know of the plastic areas in the Pacific. Are there plastic areas in the other oceans as well?
JW: Absolutely. There are probably plastics in every ocean basin. We’ve measured the ones in the Atlantic and the Pacific because we have a lot of shipping there, and a lot of research has been done there. Those regions in the mid-latitudes collect the plastic because of the way ocean circulation works. It’s a convergence zone, so the water pushes toward the middle. The plastics don't sink, so they tend to park in the middle of the convergence zone. But there are convergence zones in the Southern Hemisphere as well. And probably you could find plastics in pretty much any part of the ocean if you look hard enough. The oceans are all connected, so it’s only a matter of time that plastic will drift throughout the oceans.

JB: What does the warming of the oceans have to do with changes in precipitation? 
JW: A lot. We’ve noticed that the hydrological cycle, the cycle of water evaporating out of the ocean and falling back into the ocean or over land, is speeding up. As the atmosphere gets warmer it holds more water. So the cycle of water being evaporated out of the ocean and being spit back on land is getting faster. What that tends to mean is that wet places are getting wetter and dry places are getting drier. If you think about it, two thirds of the planet is covered by oceans. In fact a lot of the rain falls back in the oceans. The result is that the salty places in the ocean are getting saltier, and the fresh places in the oceans are getting fresher. This suggest that we are already seeing the speed up of the hydrological cycle, the water cycle. This certainly implies that rainfall and rainfall events are going to get more intense, and deserts and dry places are going to get drier. We are seeing the water cycle on steroids, and that’s what we expect in a warming world. 

JB: I’ve been aware of increased rain events in Houston, where I used to live. And of course the Gulf of Mexico is warm.
JW: Well the Gulf Stream comes out of the tropics, through the Gulf of Mexico, then goes around the southern tip of Florida and then along the East Coast of the United States. As it does, it makes that area very warm. A lot of the rain and storms that come out of the Gulf are activated by this very warm water. As that water warms up even more it gives stronger fuel to those storms. And as the air warms up more, it holds more water. So we're definitely looking at stronger precipitation events in some of the wet places, like Houston. 

JB: A question. The Gulf Stream is essential to Europe not being like an iceberg. There have been increasingly powerful rain events in the United Kingdom and some on the Continent. 
JW: We forget how important the oceans are to our climate. They cover two-thirds of the planet. All of our rainfall, or almost all of it, originates out of the oceans, so it has a dramatic effect on the climate. In Europe heat is brought into the higher latitudes by the Gulf Stream and by the Atlantic Ocean. As climate change starts to affect those currents and the ocean’s ability to move heat around, we are trying to figure out what's going to happen to the climate in Europe. If you turn off the ocean conveyor belt, the models of ocean circulation patterns point to Europe becoming colder, especially in the wintertime. But the models of global warming predict that, even if the Gulf Stream and Atlantic don’t warm Europe, global warming is still going to be the dominant effect.  So you would still see warming in Europe. But the warming might be tempered by the change in the currents and their ability to rearrange heat around the planet.

JB: Josh, there are obviously a number of currents besides the Gulf Stream. All of these currents could change, given what you're implying.
JW: Absolutely. And we’re beginning to see changes in what oceanographers call the large-scale circulations throughout the oceans, the Gulf Stream, the gyres we talked about before where all the trash collects, are all part this large-scale circulation. When the climate changes, these parts of the ocean will change along with them. We are still trying to understand how this will affect climate. Will there be more El Niños or La Niñas? We don’t know. The ocean’s role in determining how these changes will play out is big, and we’re still studying it.

JB: I have two questions: If basically no changes are made internationally on carbon dioxide or plastic pollution, what do you think may happen to sea level rise say in the next fifty years, or ocean temperature, or ocean acidity? The countries are very slow to do anything, and the Paris Agreement is not very strong. This is not looking good from what I can gather if no changes are made. 
JW: Well, there is a certain amount of warming and sea level rise that we’re already committed to. Even if we stop putting carbon dioxide in the atmosphere today, the planet would continue to warm for a long time and sea level would continue to rise for a long time – like a thousand years in terms of sea level. So we are due for more warming. The question is, how much do we want to tolerate? If we reduce our carbon consumption and reduce the amount of carbon dioxide we are putting in the atmosphere, we can still stave off the worst effects of the warming. But we are still not sure about how much increased carbon dioxide and sea level rise there will be. It could be a foot or two by the end of this century, or it could be up to six feet or even ten feet by the end of the century, which would be devastating. If that’s what we’re looking at, we already should be preparing cities to move or protect themselves from massive sea level rise. So we’re looking at an uncertain future in a lot of ways. And that uncertainty has to do with potential impacts. 

JB: I have two final questions. What can the average person do all regarding massive ice loss, sea level rise, ocean warming, and the growing acidity there?
JW: One of the most important things we can do right now is to tell our elected officials to be addressing these issues. Of course we can reduce our reliance on fossil fuels in our personal lives, get a fuel-efficient car, drive less, use less energy. California is actually moving its power grid to more and more renewable energy every year. These are really good steps. But we have to take action as a whole. We really need our leaders to start addressing this, start preparing for climate change, and also preparing to reduce our carbon footprint.  We have to find alternative means for creating energy. That’s what’s going to save us from cooking in this world. 

JB: What question haven’t I asked you that I should have asked you?
JW: Climate change is really one of the big challenges of our lifetimes, and if we want to address it, we have to act bigger. We can’t do it by ourselves. So it is important to keep this issue in mind when you participate in government, when you vote, when you talk to your Congressperson, your Senator or other elected officials. We have to try to do this together. If we do, we can probably avoid the worst of the consequences. So we have to act quickly. 

JB: Josh, thank you so much. Thank you for your time and for sharing your knowledge. 
California is actually moving its power grid to more and more renewable energy every year. These are really good steps. But we have to take action as a whole. We really need our leaders to start addressing this, start preparing for climate change, and also preparing to reduce our carbon footprint.  We have to find alternative means for creating energy. That’s what’s going to save us from cooking in this world. 

JB: What question haven’t I asked you that I should have asked you?
JW: Climate change is really one of the big challenges of our lifetimes, and if we want to address it, we have to act bigger. We can’t do it by ourselves. So it is important to keep this issue in mind when you participate in government, when you vote, when you talk to your Congressperson, your Senator or other elected officials. We have to try to do this together. If we do, we can probably avoid the worst of the consequences. So we have to act quickly. 

JB: Josh, thank you so much. Thank you for your time and for sharing your knowledge.