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San Marcos de Tarrazú, Costa Rica

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Coffee crops in San Marcos de úc, Costa Rica

Coffee production has played a central role in shaping Costa Rica's history and economy for more than 175 years. However, rising temperatures and beetle infestations that damage crops have been important factors driving coffee yields down by nearly 40 percent since 2000. Continued warming is likely to worsen the challenges already facing the Costa Rican coffee industry.1

Key Facts

Coffee has played a central role in Costa Rica's history and economic development for more than 175 years.2 Over the past several decades, warming temperatures,4,5 more frequent extreme rainfall events,5 and volatility in world markets6,7 have increased the vulnerability of the country's coffee industry.

  • Average temperatures in Costa Rica warmed by 0.9 to 1.8° F (0.5 to 1.0° C) from 1901 to 2000,4 and the number of warm days has risen by about 2.5 percent each decade since the 1970s.9,5
  • Rising temperatures have occurred along with an increase in infestations of the coffee berry borer, a pest that causes annual losses of about $500 million US$ and affects the income of more than 20 million households globally.15,16,17,22
  • Since 2000, yields of Costa Rican coffee crops have plummeted by 39 percent, and coffee production has plunged by 44 percent.8,19 Mid-range scenarios26 for future emissions of heat-trapping gases–primarily from the burning of oil, gas, and trees–project a warming of 3.2 to 9° F (1.8 to 5° C) by 2100.25 That will likely worsen environmental challenges already straining Costa Rican coffee growers.13


Costa Rica began exporting coffee in the 1830s, and coffee has played a central role in the nation's history and economic development ever since.2 In 2008, coffee was Costa Rica's third-largest export, valued at over $300 million annually.3 Since 2000, however, warming temperatures,4,5 a growing number of extreme rainfall events,5 and volatility in world coffee prices6,7 have contributed to a 44 percent plunge in Costa Rican coffee production.8

From 1901 to 2000, average temperatures in Costa Rica warmed by 0.9 to 1.8° F (0.5 to 1.0° C),4 and the number of warm days has risen by about 2.5 percent per decade since the 1970s.5 This warming–attributed to heat-trapping emissions from human activities–could prove troublesome for coffee crops.4 The arabica coffee plant's preferred temperature range is fairly narrow: between 64 and 71°/ F (18 to 22° C). Both yield and quality decline above or below that range.10 Above 93°: F (34° C), little photosynthesis takes place within the coffee plant.11

In addition to affecting the growth of coffee plants, warmer temperatures are also expanding the range of one of the most destructive coffee pests in the world: the coffee berry borer.12,13 These beetles bore into coffee berries to lay their eggs. The hatched larvae feed on the berry seeds, reducing the yield and quality of the crops.14

Before 2000, the coffee berry borer was not present in Costa Rica.15 But by 2001, it was widespread enough to warrant trapping studies,16 and by 2003 it had affected about 6 percent of Costa Rica's coffee plantations.17

Arabica coffee plants are also highly sensitive to rainfall.10 Extreme rainfall events have become more common, and have been accounting for more of Costa Rica's total rainfall, since the 1960s.18,5

The combination of rising temperatures, more extreme rainfall events, and greater prevalence of coffee berry borers may already be affecting Costa Rican coffee crops. Since 2000, coffee crop yields have dropped by 39 percent.19

Part of a Larger Pattern

The warming and increase in extreme rainfall events in Costa Rica in recent decades are part of trends occurring worldwide. Human-induced warming, caused primarily by the burning of oil, gas, and trees, has lead to more extreme rainfall events globally since the 1950s.20

Because temperature and rainfall can affect coffee plants directly, by making growing conditions less optimal, and indirectly, by enabling the success of pests such as the coffee berry borer, coffee-growing regions throughout the world are susceptible to changes in climate. In Ethiopia, for example, coffee yields declined by nearly 35 percent from 2002 to 2009 because of rising temperatures and widespread coffee berry borer infestations. 21 On a global basis, the coffee berry borer causes losses of around $500 million annually, and affects the income of more than 20 million households.22

These climate-related threats to coffee are taking place against a backdrop of volatility in the global coffee market. The collapse of the International Coffee Agreement in 1988 and 1989 led to an oversupply and a later drop in prices. Coffee prices fell to a 30-year low in 2002, threatening the livelihoods of coffee workers around the world. Reduced coffee production in turn can influence price volatility. By 2005, attempts to stabilize prices or develop new international trade agreements had not yet caught on.23

What the Future Holds

Because human-induced emissions of heat-trapping gases are rising, scientists project that temperatures in Central America will continue to increase over the course of this century. A mid-range emissions scenario would produce a warming of 3.2 to 9° F (1.8 to 5° C) by 2100.25 This warming could expand the range of the coffee berry borer,13 placing more stress on Costa Rica's coffee crops.

Future changes in rainfall have proven difficult to project, because of the complex topography of Costa Rica and its Central American neighbors, and the connection to El Niño events.25,27 However, some evidence suggests that rainfall in Costa Rica could drop during this century.27

Adaptations such as planting coffee at higher altitudes,28 and planting more shade trees to insulate coffee plants from extremes in temperatures,29 may help reduce the vulnerability of coffee growers to continued changes in temperature and rainfall.



  1. Photo used with permission from Russ Prefontaine.
  2. Gudmundson, L. 1986. Costa Rica before coffee: Society and economy on the eve of the export boom. Baton Rouge, LA: Louisiana State University Press, USA. Online at %22costa+rica%22+coffee+history&ots=6HEef8Powq&sig=DtKPagZDyAqNjSs9rdDLdSZR ejE#v=onepage&q=%22costa%20rica%22%20coffee%20history&f=false.
  3. Food and Agriculture Organization of the United Nations. 2008. FAOSTAT data for 2008. Rome, Italy. Online at
  4. Knutson, T.R., T.L. Delworth, K.W. Dixon, I.M. Held, J. Lu, V. Ramaswamy, M.D. Schwarzkopf, G. Stenchikov, and R.J. Stouffer. 2006. Assessment of twentieth–century regional surface temperature trends using the GFDL CM2 coupled models. Journal of Climate 19:1624–1651.
  5. Aguilar, E., T.C. Peterson, P. Ramírez Obando, R. Frutos, J.A. Retana, M. Solera, J. Soley, I. González García, R.M. Araujo, A. Rosa Santos, V.E. Valle, M. Brunet, L. Aguilar, L. Àlvarez, M. Bautista, C. Castañon, L. Herrera, E. Ruano, J.J. Sinay, E. Súnchez, G.I. Hernúndez Oviedo, F. Obed, J.E. Salgado, J.L. Vúzquez, M. Baca, M. Guiérrez, C. Centella, J. Espinosa, D. Martínez, B. Olmedo, C.E. Ojeda Espinoza, R. Núñez, M. Haylock, H. Benavides, and R. Mayorga. 2005. Changes in precipitation and temperature extremes in Central America and northern South America, 1961–2003. Journal of Geophysical Research 110:D23107.
  6. Amsalu, A., and E. Ludi. 2010. The effect of global coffee price changes on rural livelihoods and natural resource management in Ethiopia: A case study from Jimma Area. Bern, Switzerland: NCCR North-South Dialogue.
  7. Daniels, S., and S. Petchers. 2005. The coffee crisis continues: Situation assessment and policy recommendations for reducing poverty in the coffee sector. Boston, MA: Oxfam America. Online at
  8. U.S. Department of Agriculture, Foreign Agriculture Service. 2011. Washington, DC, USA.
  9. "Warm days" are defined as days when temperatures are above the 90th percentile.
  10. DaMatta, F.M., and J.D. Cochico Ramalho. 2006. Impacts of drought and temperature stress on coffee physiology and production: A review. Brazilian Journal of Plant Physiology 18(1):55–81.
  11. Lin, B.B., I. Perfecto, and J. Vandermeer. 2008. Synergies between agricultural intensification and climate change could created surprising vulnerabilities for crops. BioScience 58(9):847–854.
  12. Damon, A. 2000. A review of the biology and control of the coffee berry borer, Hypothenemus hampei (Coleoptera: Scolytidae). Bulletin of Entomological Research 90:453–465.
  13. Jaramillo, J. A. Chabi-Olaye, C. Kamonjo, A. Jaramillo, F.E. Vega, H.-M. Poehling, and C. Borgemeister. 2009. Thermal tolerance of the coffee berry borer (Hypothenemus hampei): Predictions of climate change impact on a tropical insect pest. PLoS ONE 4(8):e6487. doi:10.137/journal.pone.0006487.
  14. Vega, F.E., F. Infante, A. Castillo, and J. Jaramillo. 2009. The coffee berry borer, Hypothenemus hampei (Ferrari) (Coleoptera: Curculionidae): A short review, with recent findings and future research directions. Terrestrial Arthropod Reviews 2:129–147.
  15. Arrieta, G., A. Hernández, and A.M. Espinoza. 2004. Diversity of Bacillus thuringiensis strains isolated from coffee plantations infested with the coffee berry borer Hypothenemus hampei. Revista de Biología Tropical 52(3). Online at
  16. Borbón Martínez, O. 2007. Efficiency of glass traps for the monitoring and control of the coffee borer Hypothenemus hampei (Coleoptera: Curculionidae) in Costa Rica and Nicaragua. In: Anais Manejo da Broca-do-café Workshop Internacional 28 da novembro a 2 de dezembro de 2004. Londrina, Paraná, Brazil. Online at;jsessionid=0242047789401E0472758FB6C777047A.
  17. Barquero, M.S. 2003. Mil fincas afectadas por la broca. La Nación, May 23. Online at
  18. The number of extreme rainfall events is based on the number of very wet days (when precipitation is above the 95th percentile) and extremely wet days (when precipitation is above the 95th percentile), as well as maximum daily rainfall.
  19. Food and Agriculture Organization of the United Nations. 2009. FAOSTAT data for 1993–2009. Rome, Italy. Online at
  20. Min, S-K., X. Zhang, F.W. Zwiers, and G.C. Hegerl. 2011. Human contribution to more–intense precipitation extremes. Nature 470:378–381.
  21. Food and Agriculture Organization. 2009. FAOSTAT data for 1993–2009. Rome, Italy. Online at
  22. Vega, F.E., E. Rosenquist, and W. Collins. 2003. Global project needed to tackle coffee crisis. Nature 425:343.
  23. Amsalu, A., and E. Ludi. 2010. The Effect of Global Coffee Price Changes on Rural Livelihoods and Natural Resource Management in Ethiopia: A Case Study from Jimma Area. NCCR North–South Dialogue 26. Bern, Switzerland.
  24. Daniels, S. and S. Petchers. 2005. The coffee crisis continues: Situation assessment and policy recommendations for reducing poverty in the coffee sector. Oxfam America. Online at
  25. Christensen, J.H., B. Hewitson, A. Busuioc, A. Chen, X. Gao, I. Held, R. Jones, R.K. Kolli, W.–T. Kwon, R. Laprise, V. Magaña Rueda, L. Mearns, C.G. Menéndez, J. Räisänen, A. Rinke, A. Sarr and P. Whetton. 2007. Regional climate projections. In: Climate change 2007: The physical science basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, edited by Solomon, S., D. Qin, M. Manning, Z. Chen, M. Marquis, K.B. Averyt, M. Tignor, and H.L. Miller. Cambridge, UK, and New York, NY, USA: Cambridge University Press.
  26. The scenario referred to here is the middle-emissions pathway known as A1B from the Intergovernmental Panel on Climate Change.
  27. Karmalkar, A.V., R.S. Bradley, and H.F. Diaz. 2008. Climate change scenario for Costa Rican montane forests. Geophysical Research Letters 35:L11702.
  28. McPhaul, J. 2008. Global warming moves Costa Rica coffee land higher. Reuters, June 24. Online at
  29. DaMatta, F.M., C.P. Ronchi, M. Maestri, and R.S. Barros. 2007. Ecophysiology of coffee growth and production. Brazilian Journal of Plant Physiology 19(4):485–510.
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