Earth Matters

Have a Question about Climate Science? #askclimate

September 13th, 2013 by Adam Voiland


Note: See the comment thread for an archive of questions and answers related to this event.

Do you have questions about how NASA measures, models, and visualizes our changing climate?

Here’s your chance to ask them directly. Earth Observatory is hosting a climate Q & A with NASA scientists at 2 pm EDT on Wednesday, September 18. Gavin Schmidt and Benjamin Cookboth climate specialists from NASA’s Goddard Institute for Space Studies in New York Citywill be answering questions live via the @NASA_EO Twitter feed. Earth Observatory artists and writers will also be available to answer your questions about how we visualize and communicate climate data.

There’s no such thing as a dumb question. Climate change science can be confusing, complex, and controversial. Our goal is to help you cut through the noise and find out what the science actually says. Need inspiration as you think about your questions? Here are some of the more common questions we’ve received over the years.  You can also read through some of our stories about key climate change topics including: warming, aerosols, extreme storms, the water cycle, and the carbon cycle.

Start sending your questions now by posting a comment in the thread below or by sending a tweet tagged #askclimate.

[youtube G0KV2MluelY]

113 Responses to “Have a Question about Climate Science? #askclimate”

  1. Henry says:

    Thank you for this opportunity to ask question about climate change. I have few questions to ask
    1. What is the role of earth orbital variation in climate change?
    2. The sun and the human carbon emission in the atmosphere, which plays a major role in climeate change and global warming?
    3. Have there been a climate change and global warming before the era of industrialisation? If yes, then what. Caused it?
    4. If the sun refuses to dose out its energy, will the human carbon emission into space be able to cause climate change or global warming?
    5. What are the effect of space fly-bys (asteroid, cosmo, spacecraft etc) on our environment?
    I look forward to your reply
    Thank you and God bless


    • NASA Earth Observatory says:

      Q1. Very important – but mainly on long time scales (10,000s of years and up).

      Q2. Over the last two centuries carbon dioxide forcing has been around 2 W/m2, compared to trends in solar forcing of around 0.1 to 0.2 W/m2 – so for the trends carbon dioxide is more important. On the 11 year solar cycle, impacts can be seen clearly in the stratosphere.

      Q3. There are many causes of climate change – large volcanoes, impacts, continental drift, evolution(!), orbital forcing, the sun, dust, ice sheet collapses, etc. and the history of Earth has signatures of all of these. The current changes though have the fingerprints of human increases in greenhouse gases.

      Q4. If the sun ceased to shine, no amount of greenhouse gases will be sufficient to keep us warm. Thankfully that does not seem imminent.

      Q5. On climate, no effect. Though in prehistory very large impacts have clearly lead to dramatic climate changes via smoke, dust, biomass burning, and other effects (i.e. at the Cretaceous/Tertiary boundary event that marked the end of the dinosaurs)

  2. Theo says:

    How are we sure that the observed global warming is a result of man-made activities and not a random occasion which coincides with the period of industralzation, but could be a result of unexplainable change in weather pattern variability (synoptic-meso and large scale circulation)

    • NASA Earth Observatory says:

      The answer is in fingerprints of change – each kind of climate change (driven by orbital change, greenhouse gases, aerosols, volcanoes, ocean variability etc.) has a different fingerprint – the regional and temporal pattern of temperatures/rainfall etc. We look for each of the fingerprints for plausible factors and see which ones fit all the observations best. For trends over the last 50 years, it is clearly the fingerprint of greenhouse gases (particularly carbon dioxide) that fit best.

      Related Reading
      +Earth Observatory: Is Current Warming Natural?
      +Earth Observatory: Climate Forcings and Global Warming

  3. Mike says:

    Every input for every climate model has a measurement uncertainty. Those uncertainties are cumulative (and they are different from the calculation uncertainties inherent in any particular model).

    If a model has 20 inputs, there are 20 cumulative input measurement uncertainties, which must contribute to the total uncertainty of the model’s output — yet I never see a calculation of the effect of that cumulative INPUT uncertainty — why?

    • NASA Earth Observatory says:

      This isn’t how climate models are built and run. Weather models do use updates to the observations on a daily basis and you do get such drift, but the weather models are reinitialised every day and that keeps them close to reality. Climate models do not use current observations at all as an input (for most kinds of experiment), so the issue does not arise.

      Related Reading
      +Earth Observatory: Introduction to Climate Modeling.

      • Mike says:

        ??? Measurement uncertainties “do not arise?” Your own link, for example, says “The second type of model uses observed measurements that scientists have collected across the globe to generalize real processes and properties seen in nature.” Are you telling me those “observed measurements” do not have inherent uncertainties? They’re perfect?

        My question is: why don’t I ever see an accounting for those uncertainties?

  4. Shawn DeBoard says:

    Does The earth’s orbit around the ever growing SUN as a result of the expanding fabric of space time play any factor in the heat increase that the Earth is suffering from?: If so would not the only way to prolong the existence of humanity be for the human race to construct baron worlds into living worlds. Light years into the future this would include adapting worlds that support life in the parts of space that are just now going from supper hot radiation to stars then worlds. Is this the eventuality if we wish prolong life to be?

    • Sandman says:

      I think the ice cap is bigger but the volume is not. Which means this lager ice cap need to happen every year for an volume growth. The volume is still shrinking. Would be interesting to know how they know the volume is shrinking though.

    • NASA Earth Observatory says:

      The sun is growing very slowly as part of its evolution along the Main sequence. Eventually it will turn into a Red Giant and absorb the Earth completely. Luckily this is not expected to happen before the next 5 billion years.

      • wondering... says:

        how do you know it will take 5 billion years?
        I have searched newspaper archives & i cant find the last time it happened.
        you must have very good records if they date back that far!!!

  5. CSGdesign says:

    Why are we only paying attention to the data gathered in the last 50 – 100 years or so, and ignoring all the proxy data that Paleoclimatology provides to us which clearly demonstrates that the Quarternary is by far the cold exception to an otherwise much hotter earth… and that even the worst case predictions of climate change don’t even come close to returning the earth to the temperatures that it has historically been throughout the last 260 million plus years…?

    Isn’t it true that by looking at the last 100 years of data and ignoring the last 260 million years of data that it’s like saying that an old man is taking a breath inwards and therefore at this rate his chest is clearly about to explode, because we’re ignoring that his chest has been expanding and contracting for every breath he ever took previous to this one…?

    Isn’t it also true that at the beginning of the Cenazoic Era the CO2 content (greenhouse gases) in the atmosphere was basically identical to what it is today and that despite this the Earth got colder and colder until the Quarternary when it began moving in and out of ice-ages due to factors that outweighed atmospheric greenhouse gases? This evidence is inconvenient to the current climate change debate and despite being inarguable is completely ignored for the most part. I find this to be irresponsible and very narrow minded.

    For a full write-up of this please visit my article “Climate Change – Putting it into Perspective”

    All comments welcome!

  6. hiranya says:

    Why are only a few concerned about climate change, do they want to wait and watch?

    • NASA Earth Observatory says:

      Climate change is a chronic problem that is developing at a slow rate, but many people naturally focus on acute problems that affect them immediately (finding a job, feeding a family, etc). For many, it is easy to focus only on short-term concerns and to assume that someone else will deal with climate change in the future.

  7. Jim says:

    Thank you for the opportunity to ask these questions. I’m sure that may have very interesting ideas and thoughts. My question may be a bit off though. When the large quake it Japan in March, it was said that it hit so hard that the Earth shifted 4″ on it’s axis. I know it doesn’t sound like much in the big picture, but is it at all possible that this quake and the shift it caused may be the reason for the odd weather we’ve experienced since then?

    It just seems to me that since that quake, our weather patters have changed. Is this a possibility? Can a minor shift of the Earth’s axis make global weather changes?

    • MangoChutney says:

      I was thinking with India still causing the Himalayas to increase in height, is it possible the change in air currents could effect the climate until the climate reaches a tipping point (my guess is yes, but I don’t know)

      • NASA Earth Observatory says:

        Mountain building can affect climate but only over very long times frames. There is no need to worry about any imminent climate tipping points driven by tectonics.

        Related Reading
        +Cooperative Institute for Research in Environmental Sciences: Northern Tibet and Hydrological Cycle.

    • NASA Earth Observatory says:

      No. Shift in the Earth’s orbit associated even with very large earthquakes are very small compared to the shifts that cause climate change:

      Related Reading
      NASA: Japan Quake May Have Shortened Earth Days, Moved Axis.

      • MangoChutney says:

        So Hansen can spot tipping points everywhere, but the growth of mountains can never produce a tipping point – seems unlikely

  8. PaigeC says:

    Can you please respond to the claims made by Fox News on September 9, 2013 about arctic sea ice is up 60% and that we are entering a “global cooling” period? The images they show on the website are NASA images.

    Thank you!

  9. Babak says:

    I wonder what tools you use for visualizing the results and the data? If it is very general, I am mostly concerned about GeoVisualization. As an specific example, How and with what tools you have created the video in this page?

  10. BrettMT says:

    Thank you for this opportunity to ask this question. Has anyone studied the effect of the increase in sea level and it’s added weight/pressure on the sea floor? Especially on faults and subduction zones. Is the door opening for an increase is seismic activity?

    • NASA says:

      This has been studied, but bear in mind this is a very small factor compared to the ongoing plate tectonic movements (around the Pacific for instance) or the residual movement of the crust responding to the retreat of the most recent ice age about 20,000 years ago.

  11. @JPMajor via Twitter says:

    What’s the role of climate change in the #BoulderFlood? Any?

  12. @naolmstead via Twitter says:

    I would like to know about the accuracy of paleoclimate proxies and if they represent local anomalies or global trends. #askclimate

    • NASA Earth Observatory says:

      Different paleoclimate proxies provide different information at different spatial scales. For instance, tree rings are good indicators of local and regional temperature and moisture availability (i.e., drought) over the last 2000 years. Ice cores can provide much longer records of temperature (greater than 100,000 years), and also greenhouse gas concentrations.

      Related Reading
      +Earth Observatory: Paleoclimatology Introduction.

      • Nathan says:

        Thank you for answering my question. That site has a lot of really great information. However I didn’t notice anything that spoke to how scientists know the accuracy of these proxies. It did point me in some new directions of research for my personal education.

  13. @rjemmons via Twitter says:

    Without man made CO2, when would the next Pleistocene glaciation occur?

  14. @ed_hawkins via Twitter says:

    Favourite question I’ve been asked at a public climate talk: “Why does the extra heat not escape through the ozone hole?” #askclimate

    • NASA Earth Observatory says:

      This isn’t as silly as it might sound at first glance. The ozone layer plays a role in the radiative balance of the Earth and is a greenhouse gas (~ a few percent of the natural greenhouse effect). Losses in stratospheric ozone (not just in the polar ozone hole) are a negative forcing (cooling the Earth) but just at a much smaller level than the changes due to CO2 (about 10 times too small).

      Related Reading
      +Earth Observatory: Are the Ozone Hole and Global Warming Related?

  15. @JimButCallMejim via Twitter says:

    Is it possible that the Japan quake in March could shift the Earth enough to cause weather changes?

    • NASA Earth Observatory says:

      No. Shifts in the Earth’s orbit associated even with very large earthquakes are very small compared to the shifts that cause climate change.

  16. @mrtvi46 via Twitter says:

    Hey dude. Where is that warming, bro?

  17. @HiFiGuy197 Via Twitter says:

    Does buying CFLs here, made in a Chinese factory powered by coal, actually help matters? #askclimate

    • NASA Earth Observatory says:

      Yes. Manufacturing emissions are small compared to emissions saved over incandescent bulbs (most of which are also probably made in China). However, while a useful contribution, this is not sufficient to significantly bring down emissions.

  18. @jkls39 says:

    Is there a way to STOP climate change?

    • NASA Earth Observatory says:

      No. Human-caused climate change will continue because of the inertia of the climate system and human infrastucture over this century. Choices made by society will be able to make a difference between a climate change slow enough for us to adapt to, or changes that will be likely much faster than we can adapt to. Note the difference between highest and lowest lines on this graph of NASA GISS model results at

  19. @DavehanlonDavid via Twitter says:

    Will all the methane from fracking have as much impact as it seems it will?

    • NASA Earth Observatory says:

      There are multiple issues to consider. There are local ones associated with water pollution and resources. And there are climate related issues associated with replacement of coal and fugitive emissions of methane (CH4). The balance is likely to be positive. In other words, fugitive emissions are not large enough (and can be controlled with effective technologies), but long term CH4 is still a fossil fuel and contributor to the problem, just not as much as coal does.

  20. @666Ge0n says:

    Is climate modelling software developing like other technology is improving. If so, how has this effected results?

    • NASA Earth Observatory says:

      Yes. And no. Technology is improving – more elements of the climate are being added, and at finer detail and many aspects of the climate that were not modeled well are now more realistic. But in terms of the model sensitivity, or what they project for the future, the answers are very similar to previous generations of models.

  21. @Magic07 says:

    Can you link to a graph showing measured atmospheric water vapour anomaly over time increasing with CO2?

  22. @Jello_Whut says:

    What is something we can all do to help out of global warming? ‪

    • NASA Earth Observatory says:

      Global warming is dominated by human emissions of greenhouse gases like carbon dioxide. Actions like improving energy efficiency, switching suppliers to use more renewable forms of energy, and keeping the topic on the minds of policy-makers are all useful.

  23. @SherryBayhouse via Twitter says:

    Weather is an obvious consequence to climate change. What are the not so obvious consequences?

  24. @comunicacionoel via Twitter says:

    Could ENSO have a relationship with climate change?

    • NASA Earth Observatory says:

      Yes. El Niño Southern Oscillation (ENSO) patterns are the biggest kind of natural variability and they strongly impact changes from year to year. As climate changes it is conceivable that the patterns of variability will shift perhaps in frequency or spatial pattern or magnitude – but as yet we do not have a good enough understanding of the long term ENSO behavior to be able to predict how this might play out.

      Related Reading
      +Earth Observatory: El Niño, La Niña, and Rainfall
      +NOAA: NOAA’s El Niño Page.

  25. @DouglasAnders10 via Twitter says:

    Deniers are abusing the current cold spell; is this cold being balanced with tropical warming?

  26. Learnie Omega Lawrence via Facebook says:

    What caused dinosaurs to disappear, is it that they preferred primordial fluctuations which later could not recur?

  27. @JonKnight0 via Twitter says:

    Why is the clear pattern between solar activity and the warming of the planet being ignored by the media?

  28. @OniosunTemidayo via Twitter says:

    Why does water molecules in different states come together to form cloud instead of being distributed across the sky?

  29. @TLBoudell via Twitter says:

    What are the best resources for high school #science students? Is this the best link for that info? (2/2)

  30. @TroughtonC via Twitter says:

    I’m trying to simplify this conundrum for everybody so why has the weather become so controversial @NASA_EO is it interests?

  31. Brian Thomas says:

    How pleased am I to find this resource – brilliant.

    I chair a community group in NW Wales, UK which is trying to encourage our community to be more sustainable in many ways.

    We are also looking to work with a suitable enregy generataing company to develop and install a tidal turbine based electriciy generating facility; this will probably take up to 5 years to be fully operational.

    We are already getting tremendous support from our local University at Bangor N.Wales.

    We need all the help that we can get to educate the deniers and to make people aware of what they can do to improve the situation and hopefuly put the changes brought about into reverse.

    Real question – how can we convince our myopic government to take this issue seriously?

  32. @rikwes66 via Twitter says:

    Is data from antarctic expedition taken into account for #IPCC’s 5th assesment report ? #askclimate

    • NASA Earth Observatory says:

      IPCC assessment papers appeared before Mar 2013, so can’t include brand new results. Topic is, of course, included.

  33. @TLBoudell via Twitter says:

    What are the best ozone and climate change resources for high school science students?

  34. @MangoChutney via Twitter says:

    if models are so good, Y do we need more than 1, Y do they produce different results and Y didn’t 1 predict the pause?

  35. @chemphys_e via Twitter says:

    What climate model includes weakly-bound complexes in calculation of radiative capacity?

    • NASA Earth Observatory says:

      For atmospheric radiative transfer, climate models use broad-band approximations to do line-by-line calculations. If it is in there, it will be included.

  36. @TroughtonC says:

    Does the government have any recommendations for combating weather change or will we just have to adapt?

  37. @katiaepedro via Twitter says:

    Hi! How can I help to make our world get cooler, please? – Pedro Lima, 10 – Montreal,Canada.

  38. @katiaepedro via Twitter says:

    I am worried about the parks and rivers in Canada. Could you tell me about them looking from the satellites?

  39. @jbacon via Twitter says:

    How do you communicate the complexity of climate disruption without undermining the need for action?

  40. @GailxP93 via Twitter says:

    What is the main argument people have when they refute climate change?

  41. @naolmstead via Twitter says:

    Can you explain the difference in CO2 effects in the thermosphere vs troposphere? How does CO2 move up in atmosphere?

  42. @JAINER782 via Twitter says:

    Se puede restaurar la capa de ozono de forma artificial,fabricando y liberando este gas por el hombre?

    • NASA Earth Observatory says:

      La capa de ozono está en equilibrio con las condiciones ambientales de la estratosfera. Sólo podemos alterarla con una reducción de las sustancias químicas que destruyen el ozono, como los CFCs.

  43. @FabioCannondale via Twitter says:

    Existe una tasa de renovacion de la capa de ozono?

    • NASA Earth Observatory says:

      Esperamos que la capa de ozono se recuperará antes de 2030-2040 si el Protocolo de Montreal funciona como proyectado.

  44. @dubephnx via Twitter says:

    With higher volumes and intensity of hurricanes, floods, tornadoes, how important is it to make safer buildings and structures?

  45. @jbacon via Twitter says:

    What potential feedback factors are we facing in the near term (increasing/decreasing climate disruption).

  46. @EcoEastleigh via Twitter says:

    New reports indicate arctic ice very low again this summer. What impact will the complete meting have?

  47. @jbacon via Twitter says:

    When working to reduce emissions, which GHG has the most impact on climate? Methane is powerful, but CO2 persists.

  48. Gai Anderson says:

    I have seen a couple of (supposedly legit) news articles with two NASA photos of the Artic icecap….and the story that it has increased 60% over the last year…… eg

    Are the pictures and the dates bona fide? If so… there now starting to be scientific debate over whether there really is human induced warming?

  49. kamil says:

    thanks a lot for opportunity, my question is:
    whats the difference between Climate Variability and Climate Change?

  50. kamil Azarm says:

    What are the important Indices of climate change? Could we tell that rising sea levels and shrinking arctic sea ice are of these Indices?