 I'm a Zeke Hausfather and I'm with Berkeley Earth and I'm studying the surface temperature record and how to deal with all the biases and issues in it. Berkeley Earth is a re-analysis or reassessment rather than a re-analysis of global surface temperatures using a slightly different approach than most of the other groups have done in the past. So prior to this project there really was a single database that everyone used, four major groups used to reconstruct global land temperatures and that was what's called the Global Historical Calamity Logical Network monthly. It had about 7,000 stations dropping to about 1,900 in recent years and the fact that it was somewhat small database had relative areas of little spatial coverage, arctic, Africa places like that and there was such a dramatic change in the availability of data within the network led to a number of folks asking questions about whether or not any of these factors might be causing bias. So what the Berkeley effort was was an attempt to take a lot more data about 40,000 stations and use homogenization methods that were different but similar in general principle to what the National Climate Data Center does with their GHCN data and what NASA's Goddard Institute of Space Studies uses from NCDC and also use a slightly more complex spatial interpolation technique, sort of fill in all the area between these individual stations using a approach called creaking which was actually taken from sort of the geology mineral exploration space instead of what had been used to date which is a simple sort of nearest neighbor infilling spatial interpolation. At the end of the day the results really weren't that different. Globally there's pretty identical trends, slightly higher in recent years actually than most other records, very similar to the the new Compton and Way series unsurprisingly since we both used very similar methods and it also provided a really good sort of independent replication of the US temperature record because unlike the rest of the world the US has very large adjustments required because of biases in the data, primarily two things, time of observation changes, so moving when you take the temperature from the afternoon to the morning and instrument changes changing from liquid and glass thermometers to electronic instruments and the net effect of both of these and a few other things is to essentially make the raw temperature record, the reading of the thermometers about half, warm about half as much as what should actually be happening when you correct for those biases. Obviously the fact that the homogenized, the adjusted temperature data is warming twice as fast as the raw data you know caused a lot of people to raise questions about it particularly those who are predisposed to disagree with the temperature record so I think one of the more useful things to come out of the Berkeley effort at least was this sort of independent replication of US temperatures that are pretty much identical to what the National Climate Data Center found using a completely different method. You allude to this I guess suspicion of homogenization methods. Once you replicate it, did you find that suspicion in homogenization method decrease? Among some people yes, not necessarily among others. I mean frankly the general public doesn't know or understand anything about homogenization methods. We're mostly talking here about you know folks who enjoy arguing about this sort of thing on the internet or in particularly technical oriented publications and forum not the peer-reviewed literature per se where there wasn't really ever that much uncertainty but sort of in between the lay public and the peer reviewed literature. There I think we've changed a few minds but not as many as I would have hoped. It's sort of an ongoing battle because there's the certain appeal to using the raw data even if we know that the raw data may be subject to large systemic biases. At the end of the day I think that for us as a society to take the action we need to take on the climate issue we need to have more agreement on the science and I think that there is a pretty big divide between this sort of group of academic scientists who write in the peer-reviewed literature and a lot of fairly intelligent people a surprising number of them engineers who you know sort of come to their own conclusions often through things they find on the internet or sort of limited sets of information and I think there is there's certainly a set of folks who you're never going to convince for whom this issue is mostly ideological but there's also a what I would say is a pretty sizable middle of folks who you know might have some initial impressions you know they might be initially skeptical of you know what environmental groups say or what other folks who might have you know slightly different political views than them say but they can be swayed by the science and specifically they can be swayed by showing them sort of from start to finish how you approach a problem how you take a particular data set that they themselves could take if they so wanted how you analyze it what result you get and how robust that result is to your choices and you know we see this in global surface temperature data around 2010 there is this neat little movement of independent folks doing their own temperature analysis so I did my own a fellow Nick Stokes did his own reconstruction even some of the skeptics a fellow named Jeff Id with and a statistician named Roman did their own method and all of us you know pretty much found identical results Grant Foster who's a statistician also did his own approach and it was kind of neat because before then we only really had the big three governmental groups and it was kind of neat to have all these bloggers and otherwise sort of non-professional climate scientists going through the data doing their own analysis and getting the same results and I think that did actually change a lot of minds on that particular issue you know there's still other things people are going to argue about and it's always a game of whack-a-mole but I think that sort of a strong database approach to communications and journalism for that particular set of folks the sort of the engineers of the world is an effective means of communication what's your trick to I'm staying patient in the face of hostile readers just don't take it personally especially what strangers say to you on the internet and I found you know the funny thing about all this is people tend to be a lot meaner online than they are in real life and when you meet all these people and a lot of the people who you would argue with on the internet they actually tend to be pretty decent nice people you know even had a chance to meet up with our favorite cowboy Willis Sessionbach at the Burning Man Festival which is probably the last place on earth I thought I'd see so when I argue with the internet is a arched climate contrarian and you know everyone everyone's nice in person it's just something about the internet just leads people to behave a lot more costically to each other than they otherwise would if they were sitting in front of you having a conversation and I think you kind of need to bear that in mind that all these people aren't actually mean in real life all the time they're just sort of they're passionate you know they have their own political views and frankly you know our own views can shape a lot of our opinions I see that and a lot of my friends who you know are more left liberal leading in the US and their views and things like genetically engineered foods or vaccines and you know we those arguments are tough to have and so I could see how people you know who have views that lead them to disagree with the implications of climate science in terms of policy would translate that into a view on the science itself and that requires a certain amount of patience to approach them. What tips would you have for scientists in particular who are trying to communicate for science in the public? Don't talk down to your audience and don't underestimate them you know my friends and in many ways a person I look up to a lot Gavin Schmatch he's a great communicator but one of the biggest mistakes he ever made was in a public debate when he you know essentially said at the podium this is you know they're confusing you you know this is too complicated for you guys to understand easily. Trust me I'm a scientist sort of approach and I think that sort of approach by itself really turns people off. I think that appeals to consensus are useful if accompanied by other information around the issue I think by themselves or appeals to authority are not necessarily productive and sort of on the flip side of that is you know your audience is smart enough to understand your argument and so don't be afraid to be a little bit technical I mean don't go completely off the rails into jargon filled things that your audience can never understand but you know treat your audience like grown-ups maybe if you need to have an addendum at the end of something you're writing but provide them the details and provide them the data sources the links to the peer-reviewed publication so people can follow and look it up themselves because a surprising number of people actually spend enjoy spending far too much time looking at these things well it's it's it's really simple at the heart of it I mean CO2 is a greenhouse gas no one disagrees with that even the you know most arch climate skeptics in the world who are in academia the Dick Linsons of the world still say that CO2 is a greenhouse gas and heat-seeking missiles wouldn't work if CO2 wasn't a greenhouse gas the military would obviously have some issues with that. Humans are responsible for the bulk of modern CO2 emissions we can measure it we know how much we're burning we know how much is accumulating the atmosphere it's not very difficult and so it's very easy to figure that out and increased CO2 causes warming because CO2 is a greenhouse gas you know the radiative physics that are easily and well understood so if you accept those things you know CO2 emissions or the third part is atmospheric CO2 is increasing again we have really good measures of this from ice cores and other things and there's really no uncertainty in that so if you accept those three things CO2 is increasing humans are responsible for most of the additional CO2 in the atmosphere and CO2 is a greenhouse gas and so more of it causes warming then humans are responsible for global warming to some extent or another and you know I think just emphasizing those three things gets us a long way there's plenty to argue about in the details around what is climate sensitivity and exactly how much of the warming in different periods of time or humans are responsible for but at the end of the day the world is warming we are responsible for certainly a portion of it and most people think a large portion of it and there's very good reason to think that because of those simple reasons there's just something about the semi anonymity and an anonymousness of the internet anonymity I don't know what the form is