1 / 22

Thomas Giambelluca University of Hawai‘i at Mānoa

GLOBAL CHANGE THREATS TO HYDROLOGY & TERRESTRIAL ECOSYSTEMS: IMPACTS OF GLOBAL WARMING & SPECIES INVASION IN HAWAI‘I. Thomas Giambelluca University of Hawai‘i at Mānoa. EPSCoR Water Dynamics Workshop Burlington, VT 10 November 2008. Water, water, everywhere. Setting

eris
Download Presentation

Thomas Giambelluca University of Hawai‘i at Mānoa

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. GLOBAL CHANGE THREATS TO HYDROLOGY & TERRESTRIAL ECOSYSTEMS: IMPACTS OF GLOBAL WARMING & SPECIES INVASION IN HAWAI‘I Thomas Giambelluca University of Hawai‘i at Mānoa EPSCoR Water Dynamics Workshop Burlington, VT 10 November 2008

  2. Water, water, everywhere . . . Setting • Extreme geographical isolation • High water demand • High inter-annual rainfall variability • Prone to water shortage

  3. Expectations and observations of warming shift attention to higher latitude land areas High-latitudes: +2.3oC 1920-2005 Tropics: +0.8oC 1920-2005 Source: AR4, IPCC (2007)

  4. However, while land areas have warmed fastest at high latitudes, warming of the Pacific Ocean shows cyclical patterns with respect to latitude Source: AR4, IPCC (2007)

  5. Pacific Decadal Oscillation (PDO) Source: AR4, IPCC (2007); also see Mantua et al. (1997) and Power et al. (1999)

  6. El Niño-Southern Oscillation(ENSO) Source: AR4, IPCC (2007); also see Trenberth and Caron (2000)

  7. Hawai‘i Temperature Index GLOBAL TRENDS: 1906-2005: 0.074oC per decade 1976-2005: 0.177oC per decade Source: AR4, IPCC (2007) Source: Giambelluca et al. (2008)

  8. HTI—PDO—SST PDO SST Source: Giambelluca et al. (2008)

  9. Hot Nights *Significant at p = 0.5 Source: Giambelluca et al. (2008)

  10. Decrease in Day-Night Temperature Difference Source: Giambelluca et al. (2008)

  11. Hawai‘i Rainfall: Long-Term Decrease Hawai‘i (winter) Rainfall Index (HRI) Source: Chu and Chen (2005)

  12. Trade-Wind Inversion • Mean altitude ~2200 m (7200 ft) • Frequency ~80% • Stable atmospheric layer • Forms a barrier to rising air • Because rising air is the predominant means by which clouds form, cloud development is capped at the TWI level • As a result, relatively thin clouds produce less precipitation when TWI is present • Climate changes resulting in either more frequent or lower altitude TWI will cause a reduction in rainfall

  13. Effect of Inversion on Rainfall HaleNet: Haleakalā Maui Source: Adapted from Tran (1995)

  14. Effect of Inversion on Rainfall HaleNet: Haleakalā Maui Source: Adapted from Tran (1995)

  15. TWI Trends Source: Cao et al. (2007)

  16. Warming and Ecosystem Services Asner et al. (in review)

  17. Warming & Carbon Dynamics • Native forest site currently a net carbon sink (2.8-3.4 Mg C ha-1 yr-1) • Gross primary production controlled mainly by PAR • Ecosystem respiration controlled by temperature • Each 1ºC increase in temperature causes a 15% increase in respiration loss • Warming may reduce competitiveness of native trees versus invasive trees

  18. Species Invasion & Hydrological Services • Species invasion is a major environmental problem in Hawai‘i • Success of invasive trees may be facilitated by warming • What secondary impacts do these trees have on hydrological services? • Psidium cattleianum is the most widespread invasive tree in Hawaii

  19. Field Sites • Invaded Forest Site • ‘ohia forest invaded by Psidium cattleianum (strawberry guava) • Native Forest Site • Metrosideros polymorpha (‘ohia) • Cibotium spp. (hapu‘u; tree fern)

  20. ETinvaded 27% more than ETnative ET Available Energy

  21. SUMMARY • Hawai‘i is highly vulnerable to and prone to water shortage • Tropical areas like Hawai‘i are subject to significant impacts of global warming • Trends suggest Hawai‘i is getting warmer and drier • Warming will have negative impacts on native forests and favor invasive trees • Invasive trees can significantly reduce water availability • Findings suggest severe combined and synergistic effects of climate change and species invasion on Hawai‘i’s terrestrial ecosystems and their services

  22. THANK YOU thomas@hawaii.edu

More Related