Environmental Impacts

In addition to extraterrestrial environmental impacts, such as orbital debris and the effect on possible extraterrestrial life, current and possible future space activities have several significant impacts on Earth.

Ozone Depletion

Of several terrestrial impacts of spaceflight, ozone depletion may be the most serious 1. Some rocket fuels release particles in the stratosphere, especially aluminum oxide, that deplete ozone. Some estimates of this depletion are as follows.

Annual Number of Flights ConsideredTotal Ozone DepletionDepletion Per Annual FlightNotes
87 20.025%0.00029%Ozone depletion is assessed for all flights that year 3.npm
15 40.25%0.017%
10,000 50.2%0.00002%Ozone depletion is given in Dobson Units. We take total atmospheric ozone concentration of 100 DU 6.
100,000 50.4-1.5%0.000004-0.000015%See above.
300,000 53.5-3.9%0.000012-0.000013%See above.
1,000,000 511%0.000011%See above.
1000 71%0.001%
114 80.01-0.1%0.000088-0.00088%Assesses impact of all launches, which were 114 in 2018 3.

Estimates of the ozone depletion effect of rocket launches vary due to physical uncertainties, variation in the modelled types of rockets and rocket fuel, and other factors. By way of comparison, stratospheric ozone declined 60% from 1979 to 1994, from which point it has slightly recovered 9.

The reentry of satellites into the atmosphere is also a potential concern for ozone depletion 10. Due to the wide uncertainty in the amount of ozone depletion resulting from rocket launches, more research is needed.

Problem:
Ozone Depletion
Solution:
Low-depletion rocket fuels

Climate

Rockets consume energy and release carbon dioxide emissions, but they have a much greater impact on the climate through stratospheric emissions and their effects. As of 2014, launches were estimated to cause 0.016 (± 0.008) watts per square meters of radiative forcing 11. By way of comparison, the International Panel on Climate Change's scenarios for 21st century global warming are between 2.6 and 8.5 watts per square meter 12. Causes of warming are estimated as follows.

The image: "rocket_warming.svg" cannot be found!

Source: 11.

Other research suggests that an expansion of the spaceflight industry to 100,000 launches per day would cause between -0.01 and +0.08 W/m2 of warming 5. As with ozone depletion, there is great uncertainty and limited knowledge in this area.

Energy and Emissions

We estimate the energy consumption and resulting greenhouse gas emissions of rocket launch as follows.

The image: "launch_energy.svg" cannot be found!

Launch energy of the Falcon Heavy, including the primary energy behind the RP-1 rocket fuel and liquid oxygen, but not to manufacture the rocket or other upstream costs. Total fuel needs and payload mass are estimated from Spaceflight 101 13, energy intensity of kerosene (of which RP-1 is a variant) from MacKay 14, LOX from Shen and Wolsky 15, and primary energy conversions from Building Energy Codes Program 16.

From 2016 to 2018, launch destinations were as follows.

The image: "launch_targets.svg" cannot be found!

Source: Kyle 3.

Assuming all rockets have the same energy to liftoff payload mass ratio as the Falcon Heavy, launches consumed about 336 terajoules of primary energy in 2020, or about 0.000055% of world total 3. This supports a commercial satellite market worth $2.5 billion in 2019 and projected to grow to $4.7 billion in 2025 17. Actual energy needs are higher when embodied energy--the energy required to manufacture rockets and other upstream costs--are included, but we expect that the figure will remain a miniscule share of world energy.

Other Effects

In an environmental impact statement conducted for Space Shuttle activities at the Kennedy Space Center (KSC) 18, NASA observed that the KSC is located at an ecologically sensitive area and is home to more endangered and threatened species than any other federal facility. Heavy metals and other soil pollutants were found immediately by the launch pads, and some animals, though no threatened or endangered animals, died in the blasts resulting from launch. Fast ecological recovery was noted after the end of the space shuttle program and in the lull following the Challenger disaster.

See also our review of energy generation in space and its impacts.

References

  1. Dallas, J. A., Raval, S., Alvarez Gaitan, J. P., Saydam, S., Dempster, A. G. "The environmental impact of emissions from space launches: A comprehensive review". Journal of Cleaner Production 255: 120209. May 2020.

  2. Jackman, C. H., Considine, D. B., Fleming, E. L. "A global modeling study of solid rocket aluminum oxide emission effects on stratospheric ozone". Geophysical Research Letters 25(6), pp. 907-910. March 1998.

  3. Kyle, E. "Space Launch Report". Accessed November 8, 2019. 2 3 4

  4. Prather, M. J., García, M. M., Douglass, A. R., Jackman, C. H., Ko, M. K. W., Dak Sze, N. "The space shuttle's impact on the stratosphere". Journal of Geophysical Research: Atmospheres 95(D11), pp.18583-18590. October 1990.

  5. Larson, E. J. L., Portmann, R. W., Rosenlof, K. H., Fahey, D. W., Daniel, J. S., Ross, M. N. "Global atmospheric response to emissions from a proposed reusable space launch system". Earth's Future 5(1), pp. 37-48. January 2017. 2 3 4 5

  6. Ritchie, H., Roser, M. "Ozone Layer". Our World in Data. June 2018.

  7. Ross, M., Mills, M., Toohey, D. "Potential climate impact of black carbon emitted by rockets". Geophysical Research Letters 37(24). December 2010.

  8. Ross, M., Vedda, J. A. "The Science and Policy of Rocket Emissions". The Aerospace Corporation. April 2018.

  9. NASA Earth Observatory. "World of Change: Antarctic Ozone Hole". Accessed August 17, 2021.

  10. Boley, A. C., Byers, M. "Satellite mega-constellations create risks in Low Earth Orbit, the atmosphere and on Earth". Scientific Reports 11(1), pp. 1-8. May 2021.

  11. Ross, M. N., Sheaffer, P. M. "Radiative forcing caused by rocket engine emissions". Earth's Future 2(4), pp. 177-196. April 2014. 2

  12. IPCC. "Summary for Policymakers". In Climate Change 2013: The Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change [^Stocker, T.F., D. Qin, G.-K. Plattner, M. Tignor, S.K. Allen, J. Boschung, A. Nauels, Y. Xia, V. Bex and P.M. Midgley (eds.)]:. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA. 2013.

  13. Spaceflight 101. "Falcon Heavy". Accessed November 7, 2019.

  14. MacKay, D. "Sustainable Energy - Without the Hot Air". UIT Cambridge, ISBN 978-0-9544529-3-3. Available free online from www.withouthotair.com. 2008.

  15. Shen, S., Wolsky, A. "Energy and materials flows in the production of liquid and gaseous oxygen". August 1980.

  16. Building Energy Codes Program. "Prototype Building Models High-rise Apartment". Building Technologies Office, Office of Energy Efficiency and Renewable Energy, U. S. Department of Energy. April 2011.

  17. Global Newswire. "The Global Commercial Satellite Imaging Market size is expected to reach $4.7 billion by 2025, rising at a market growth of 11.3% CAGR during the forecast period". October 2019.

  18. Hall, C. R., Schmalzer, P. A., Breininger, D. R., Duncan, B. W., Drese, J. H., Scheidt, D. A., Lowers, R. H., Reyier, E. A., Holloway-Adkins, K. G., Oddy, D. M., Cancro, N. R., Provancha, J. A., Foster, T. E., Stolen, E. D. "Ecological Impacts of the Space Shuttle Program at John F. Kennedy Space Center, Florida". NASA/TM-2014–216639. January 2014.