State of the Planet

News from the Columbia Climate School

tree rings3

  • Tree Rings on Hawai’i Could Hold New Knowledge About El Niño

    Tree Rings on Hawai’i Could Hold New Knowledge About El Niño

    Annual tree rings are a rare find in the tropical islands of the eastern Pacific. The new discovery of trees with annual rings on a Hawaiian volcano could provide new climate data from a part of the world where much of the variability of the El Niño-Southern Oscillation originates.

  • Learning from a River’s History to Prepare for the Future

    Learning from a River’s History to Prepare for the Future

    Researchers from eight universities, including Columbia University, are using tree ring and glacier analysis to reconstruct the climate history of the Missouri River Basin in order to give policymakers and water managers better decision-making tools to manage the river.

  • World Trade Center Ship Traced to Colonial-Era Philadelphia

    World Trade Center Ship Traced to Colonial-Era Philadelphia

    Four years ago this month, archeologists monitoring the excavation of the former World Trade Center site uncovered a ghostly surprise: the bones of an ancient sailing ship. In a new study, scientists at Lamont-Doherty Earth Observatory say that an old growth forest in the Philadelphia area supplied the white oak used in the ship’s frame,…

  • The Pluvial Continues… Has the Long Rain Epoch Begun?

    The Pluvial Continues… Has the Long Rain Epoch Begun?

    Daily comparisons on TV or other media sources are typically based upon recent climate and ignore the past. Dased upon paleo records, the full picture indicates that we are sitting in one of the more unusually wet periods of the last 500 years.

  • Climate and Conquest: How Did Genghis Khan Rise?

    Climate and Conquest: How Did Genghis Khan Rise?

    Eight hundred years ago, relatively small armies of mounted warriors suddenly exploded outward from the cold, arid high-elevation grasslands of Mongolia and reshaped world geography, culture and history in ways that still resound today. How did they do it?

  • Out of the Woods

    Out of the Woods

    When we walked into the Sheraton in Springfield, Massachusetts we were greeted by none other than a wall full of cross sections from trees perfectly sanded to reveal the rings. “No way” I say. “I forgot the camera!” says Neil. We were just walking into the Northeast Natural History Conference, along with Dario and Jackie…

  • Visual Skateboarding

    Visual Skateboarding

    “You can do math on excel?” I ask. I immediately imagine a face-palm response, but Dario, one of my advisors, is nice enough to hide it. I’ve collected tree core samples, I’ve prepared them and cross-dated them. Now what? Oh, right. The Science.

  • I’ll Go on a Cross-Date if You Show Me Some Rings

    I’ll Go on a Cross-Date if You Show Me Some Rings

    Ever since I’ve started learning to cross-date tree core samples, I’ve learned I have a type. I prefer my tree cores to be black oaks, middle-aged, with some nice big rings to show me. Alright, fine, I can deal with some smaller rings every now and then. As long as they’re some nice marker rings.…

  • Tree Rings and Teachable Moments

    Tree Rings and Teachable Moments

    Nicole Davi, a postdoctoral scientist at the International Research Institute for Climate and Society and the Lamont Doherty Earth Observatory, thinks tree rings are an ideal way to motivate students to collect and analyze data as well as to learn about climate change.

Photo of the Earth from space with the text "Lamont at AGU25" on top.

AGU25, the premier Earth and space science conference, takes place December 15-19, 2025 in New Orleans, Louisiana. This year’s theme—Where Science Connects Us—puts in focus how science depends on connection, from the lab to the field to the ballot box. Once again, Lamont-Doherty Earth Observatory and Columbia Climate School scientists, experts, students, and educators are playing an active role, sharing our research and helping shape the future of our planet. #AGU25 Learn More

  • Tree Rings on Hawai’i Could Hold New Knowledge About El Niño

    Tree Rings on Hawai’i Could Hold New Knowledge About El Niño

    Annual tree rings are a rare find in the tropical islands of the eastern Pacific. The new discovery of trees with annual rings on a Hawaiian volcano could provide new climate data from a part of the world where much of the variability of the El Niño-Southern Oscillation originates.

  • Learning from a River’s History to Prepare for the Future

    Learning from a River’s History to Prepare for the Future

    Researchers from eight universities, including Columbia University, are using tree ring and glacier analysis to reconstruct the climate history of the Missouri River Basin in order to give policymakers and water managers better decision-making tools to manage the river.

  • World Trade Center Ship Traced to Colonial-Era Philadelphia

    World Trade Center Ship Traced to Colonial-Era Philadelphia

    Four years ago this month, archeologists monitoring the excavation of the former World Trade Center site uncovered a ghostly surprise: the bones of an ancient sailing ship. In a new study, scientists at Lamont-Doherty Earth Observatory say that an old growth forest in the Philadelphia area supplied the white oak used in the ship’s frame,…

  • The Pluvial Continues… Has the Long Rain Epoch Begun?

    The Pluvial Continues… Has the Long Rain Epoch Begun?

    Daily comparisons on TV or other media sources are typically based upon recent climate and ignore the past. Dased upon paleo records, the full picture indicates that we are sitting in one of the more unusually wet periods of the last 500 years.

  • Climate and Conquest: How Did Genghis Khan Rise?

    Climate and Conquest: How Did Genghis Khan Rise?

    Eight hundred years ago, relatively small armies of mounted warriors suddenly exploded outward from the cold, arid high-elevation grasslands of Mongolia and reshaped world geography, culture and history in ways that still resound today. How did they do it?

  • Out of the Woods

    Out of the Woods

    When we walked into the Sheraton in Springfield, Massachusetts we were greeted by none other than a wall full of cross sections from trees perfectly sanded to reveal the rings. “No way” I say. “I forgot the camera!” says Neil. We were just walking into the Northeast Natural History Conference, along with Dario and Jackie…

  • Visual Skateboarding

    Visual Skateboarding

    “You can do math on excel?” I ask. I immediately imagine a face-palm response, but Dario, one of my advisors, is nice enough to hide it. I’ve collected tree core samples, I’ve prepared them and cross-dated them. Now what? Oh, right. The Science.

  • I’ll Go on a Cross-Date if You Show Me Some Rings

    I’ll Go on a Cross-Date if You Show Me Some Rings

    Ever since I’ve started learning to cross-date tree core samples, I’ve learned I have a type. I prefer my tree cores to be black oaks, middle-aged, with some nice big rings to show me. Alright, fine, I can deal with some smaller rings every now and then. As long as they’re some nice marker rings.…

  • Tree Rings and Teachable Moments

    Tree Rings and Teachable Moments

    Nicole Davi, a postdoctoral scientist at the International Research Institute for Climate and Society and the Lamont Doherty Earth Observatory, thinks tree rings are an ideal way to motivate students to collect and analyze data as well as to learn about climate change.