Simulation of Pollen Transport by Wind: II. Numerical Experiments and Comparisons with Observations

The research paper tests a Cellular Automaton (CA) model to simulate how wind velocity, turbulence, and source field size affect pollen dispersal. By using wind data from Dunkeswell, UK, and comparing results to historical field data from the US and other regions, the authors demonstrate that the model provides a good approximation of pollen deposition. A key finding is that pollen deposition is often 'patchy,' forming 'fingers' or 'islands' of high concentration, which suggests that fixed separation distances for GM crop co-existence are unreliable.

• The CA model demonstrates that pollen deposition patterns are highly sensitive to wind speed; higher wind speeds increase the distance pollen travels, and the extent of the deposit scales with the average propagation speed of the pollen.
• Pollen deposition is characterized by non-uniform, 'patchy' distributions, including high-concentration 'tongues' or 'fingers' and isolated islands, caused by space- and time-dependent wind components and turbulence.
• The model's results for pollen deposition as a function of distance align well with historical observations of seven grass species, with a sticking probability (PsF) of 0.1 serving as a reasonable guideline for simulations.
• Comparisons with maize outcrossing data from Oklahoma (1947-1949) show that the CA model can closely fit observed curves by adjusting sticking probability and wind speed, reflecting how rainy weather and low wind velocity in 1948 reduced outcrossing.
• The authors argue that established separation distances for the co-existence of GM and non-GM crops are unreliable because unusually strong winds can carry pollen much further than average, and the 'patchy' nature of deposition means individual plants may exceed legal contamination limits.
• While the CA model focuses on low-altitude wind, evidence suggests high-altitude winds can transport pollen over vast distances, such as Betula pollen traveling over 2000 km from Russia, the Baltic states, and Poland to Sweden and Finland.

APA

Novotny, E., & Perdang, J. (n.d.). Simulation of Pollen Transport by Wind: II. Numerical Experiments and Comparisons with Observations. Scientists for Global Responsibility. https://www.sgr.org.uk/sites/default/files/PollenTransport-Paper II-final-SGR.pdf

Chicago

Novotny, E, and J. Perdang. Simulation of Pollen Transport by Wind: II. Numerical Experiments and Comparisons with Observations. Scientists for Global Responsibility, n.d. https://www.sgr.org.uk/sites/default/files/PollenTransport-Paper II-final-SGR.pdf.

Wikipedia

{{cite report |last1=Novotny |first1=E |last2=Perdang |first2=J. |title=Simulation of Pollen Transport by Wind: II. Numerical Experiments and Comparisons with Observations |publisher=Scientists for Global Responsibility |url=https://www.sgr.org.uk/sites/default/files/PollenTransport-Paper II-final-SGR.pdf |access-date=23 October 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{novotnyndsimulation, author = {Novotny, E and Perdang, J.}, title = {{Simulation of Pollen Transport by Wind: II. Numerical Experiments and Comparisons with Observations}}, institution = {Scientists for Global Responsibility}, url = {https://www.sgr.org.uk/sites/default/files/PollenTransport-Paper II-final-SGR.pdf}, urldate = {2026-10-23}, note = {Indexed by Climate Insights Directory} }