full transcript

From the Ted Talk by David Keith: A critical look at geoengineering against climate change

Unscramble the Blue Letters

I'll tell you very quickly how the effect works. There are a lot of fun complexities that I'd love to spned the whole evening on, but I won't. But let's say you have sunlight hittnig some particle and it's unevenly heated. So the side facing the sun is warmer; the side away, cooler. Gas molecules that bounce off the warm side bocune away with some extra velocity because it's warm. And so you see a net force away from the sun. That's called the photophoretic force. There are a bunch of other versions of it that I and some collaborators have thought about how to exploit. And of course, we may be wrong — this hasn't all been peer reviewed, we're in the middle of tnnkhiig about it — but so far, it seems good. But it looks like we could achieve long atmospheric lifetimes — much logenr than before — because they're levitated. We can move things out of the ssaeorptrthe into the meohrpesse, in principle solving the ozone prlobem. I'm sure there will be other problems that arise. Finally, we could make the particles migrate to over the poles, so we could arrange the cltamie erneienging so it really focused on the poles. Which would have minimal bad impacts in the mildde of the planet, where we live, and do the maximum job of what we might need to do, which is cooling the poles in case of planetary emergency, if you like.

Open Cloze

I'll tell you very quickly how the effect works. There are a lot of fun complexities that I'd love to _____ the whole evening on, but I won't. But let's say you have sunlight _______ some particle and it's unevenly heated. So the side facing the sun is warmer; the side away, cooler. Gas molecules that bounce off the warm side ______ away with some extra velocity because it's warm. And so you see a net force away from the sun. That's called the photophoretic force. There are a bunch of other versions of it that I and some collaborators have thought about how to exploit. And of course, we may be wrong — this hasn't all been peer reviewed, we're in the middle of ________ about it — but so far, it seems good. But it looks like we could achieve long atmospheric lifetimes — much ______ than before — because they're levitated. We can move things out of the ____________ into the __________, in principle solving the ozone _______. I'm sure there will be other problems that arise. Finally, we could make the particles migrate to over the poles, so we could arrange the _______ ___________ so it really focused on the poles. Which would have minimal bad impacts in the ______ of the planet, where we live, and do the maximum job of what we might need to do, which is cooling the poles in case of planetary emergency, if you like.

Solution

  1. bounce
  2. longer
  3. mesosphere
  4. middle
  5. climate
  6. engineering
  7. thinking
  8. stratosphere
  9. spend
  10. hitting
  11. problem

Original Text

I'll tell you very quickly how the effect works. There are a lot of fun complexities that I'd love to spend the whole evening on, but I won't. But let's say you have sunlight hitting some particle and it's unevenly heated. So the side facing the sun is warmer; the side away, cooler. Gas molecules that bounce off the warm side bounce away with some extra velocity because it's warm. And so you see a net force away from the sun. That's called the photophoretic force. There are a bunch of other versions of it that I and some collaborators have thought about how to exploit. And of course, we may be wrong — this hasn't all been peer reviewed, we're in the middle of thinking about it — but so far, it seems good. But it looks like we could achieve long atmospheric lifetimes — much longer than before — because they're levitated. We can move things out of the stratosphere into the mesosphere, in principle solving the ozone problem. I'm sure there will be other problems that arise. Finally, we could make the particles migrate to over the poles, so we could arrange the climate engineering so it really focused on the poles. Which would have minimal bad impacts in the middle of the planet, where we live, and do the maximum job of what we might need to do, which is cooling the poles in case of planetary emergency, if you like.

Frequently Occurring Word Combinations

ngrams of length 2

collocation frequency
climate change 4
reduce emissions 3
cutting emissions 3
moral hazard 3
red line 2
arctic sea 2
sea ice 2
cheap meaning 2
ozone layer 2
cut emissions 2
national academy 2
climate engineering 2
climate impacts 2

Important Words

  1. achieve
  2. arise
  3. arrange
  4. atmospheric
  5. bad
  6. bounce
  7. bunch
  8. called
  9. case
  10. climate
  11. collaborators
  12. complexities
  13. cooler
  14. cooling
  15. effect
  16. emergency
  17. engineering
  18. evening
  19. exploit
  20. extra
  21. facing
  22. finally
  23. focused
  24. force
  25. fun
  26. gas
  27. good
  28. heated
  29. hitting
  30. impacts
  31. job
  32. levitated
  33. lifetimes
  34. live
  35. long
  36. longer
  37. lot
  38. love
  39. maximum
  40. mesosphere
  41. middle
  42. migrate
  43. minimal
  44. molecules
  45. move
  46. net
  47. ozone
  48. particle
  49. particles
  50. peer
  51. photophoretic
  52. planet
  53. planetary
  54. poles
  55. principle
  56. problem
  57. problems
  58. quickly
  59. reviewed
  60. side
  61. solving
  62. spend
  63. stratosphere
  64. sun
  65. sunlight
  66. thinking
  67. thought
  68. unevenly
  69. velocity
  70. versions
  71. warm
  72. works
  73. wrong