Dot Earth Turns Five Years Old Dot Earth began five years and 2,000 posts ago as an open exploration of ways to smooth the human journey in a fast-motion century on a finite planet. A narrated slide show describes how this came about. The image above is part of a "thought map" drawn by New York Times blog specialist Jeremy Zilar on a whiteboard in one of the conference rooms at The Times as he and I tossed around different ways to develop and organize the core themes. I'd appreciate input from readers on next steps, technical or thematic suggestions and other feedback. Here are a few themes to consider: Comments. As longtime visitors know, I've tried various ways to foster constructive online discourse, which is never easy given the tendency of the Web to amplify and polarize. I would still love to see more comment contributors provide YouTube messages as a way to personalize the exchanges here. They can now be embedded by me directly in the comment string. Methods. I'd like to do more pieces like "Beyond the Eternal Food Fight" and "Debate Over Climate Risks - Natural or Not," in which I convene via e-mail a batch of experts on issues related to sustainable human advancement. What themes would you like explored that way? To me, this is the best approach to fostering understanding of the critical questions that lie between Wikipedia entries or Times topics pages. As I explained in a talk Tuesday night at the University of Missouri, examining arguments and points of agreement is the best path forward when in such terrain. Think of the difference between these questions: How do greenhouse gases function? That's a Wikipedia entry. How dangerous is global warming? This is a question with no single, easy answer. Tools. I plan to start (hopefully regular) Google+ Hangouts on Air on issues in the news. These are live Web video chats involving up to 10 people at a time that are recorded and archived on YouTube. Have a look at the Hangouts produced by Stanford climate scientist Noah Diffenbaugh to get the idea. Community. I need desperately to update my blogroll, the resource list to the right. What blogs or Web sites do you think I'm missing? This passage from one of my posts on day one -- Oct. 24, 2007 -- still serves well as an articulation of why I think blogging (at least the way I do it) is a useful enterprise: The strength of science lies in the trajectory of understanding more than in any single finding, and the most durable ideas emerge from conversation, not monologue. So for me, a blog offers an ideal way to interact with the world, and with an audience - one that tracks and tests ideas over time and has the feel of a jam session more than a formal, static solo performance.... I've decided to focus Dot Earth on the broad-brush theme of sustainability for a few reasons. One is that "slow drip" issues are hard to capture and convey through traditional media tools, which are mostly (and appropriately) focused on dramatic events happening now, not eventually momentous trends that hide in plain sight. Another is that some of the underlying problems related to humanity's impact on the environment are largely irreversible. The greenhouse effect appears a lot easier to amplify than to reduce. Extinction is forever (at least for now). Such issues deserve sustained attention. Sustained, indeed.... I'm still not quite sure how I sustained a one-a-day posting pace through five years. The suggestion box is open.