Hydrological Impacts of LCLU Changes and Global Climate Change
Hydrological Impacts of LCLU Changes and Global Climate Change in Tropical Islands
Daniel E. Comarazamy and Jorge E. Gonzalez NOAA-CREST, Department of Mechanical Engineering, The City College of New York, New York, NY
Outline INTRODUCTION
RELEVANT CLIMATE CHANGE STUDIES IN COASTAL TROPICAL REGIONS
OBJECTIVES METHODOLOGY
CASE OF SAN JUAN, PUERTO RICO
LCLU CHANGE
GLOBAL CLIMATE CHANGE
NUMERICAL EXPERIMENT MATRIX
RESULTS
CLIMATE IMPACTS OF LCLU CHANGES AND GLOCAL CLIMATE CHANGE IN COASTAL TROPICAL REGIONS
SUMMARY AND CONCLUSION
QUESTIONS AND COMMENTS
LCLU Changes Studies in Tropical Regions • Climate impact studies due to LCLU changes have been performed with combined observational and numerical components. • Velazquez et al. 2006 (San Juan, PR) - Urbanization • Lawton et al. 2001; Nair et al. 2003; Ray et al. 2006 (Monteverde, CR) - Deforestation • van der Molen, 2002; van der Molen et al. 2006 (Puerto Rico) - Deforestation and Reforestation • Some of the drawbacks of these studies is that the modeling is simplified and not all effects are included, analyzed, or separated.
Objectives An attempt to bridge the knowledge gap in the matter of the impact of LCLU changes in tropical coastal regions in a changing environment will be made by trying to answer the following questions: 1. What is the relative effect of historical LCLU changes on the climate of tropical coastal regions? 2. What is the relative climatic impact of global climate change in tropical coastal regions? 3. Under these conditions of LCLU and global climate change, what is the combined effect in tropical coastal regions?
Methodology / Numerical Experiments To answer the posed research questions, a series of numerical atmospheric simulations are proposed to separate the signals of LCLU change and global climate change. The Regional Atmospheric Modeling System (RAMS) will serve as the main research tool. General Model Configuration Grid 1 Grid 2 Grid 3 Δx = Δy
25km
5km
1km
σ-coordinate vertical
CPU time
Δσ = 30m near sfc until Δσ = 1km, model top at ~25km Approximately 5 to 6 days for a 30-day simulation Model grids with topography (contour interval: 150m)
Case of SJMA, Puerto Rico
Case of SJMA, Puerto Rico • Puerto Rico offers a great opportunity for LCLU change impact studies because: • The close proximity of the San Juan Metropolitan Area (SJMA), the Luquillo Experimental Forest (LEF), and the Central Mountain range • Evidence of combined global and local effects on regional climate • Historical LCLU practices (i.e., agriculture, urbanization, deforestation, reforestation) • The recently drafting and implementation of the Puerto Rico Land Use Plan
LCLU Specifications - Northeastern PR 1951
2000+ATLAS
IPCC WG1 4th Assessment Report: Climate Change 2007, The Physical Science Basis
Trenberth, K.E., et al., 2007: Observations: Surface and Atmospheric Climate Change. 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 [Solomon, S., et al. (eds.)]
IPCC WG1 4th Assessment Report: Climate Change 2007, The Physical Science Basis
Trenberth, K.E., et al., 2007: Observations: Surface and Atmospheric Climate Change. 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 [Solomon, S., et al. (eds.)]
Numerical Experiment Matrix
*
Run ID
LCLU
Driving Conditions**
Present1*
2000+ATLAS
2000-04 Atmospheric Conditions
Present2
2000+ATLAS
1955-59 Atmospheric Conditions
Past1
1951
2000-04 Atmospheric Conditions
Past2
1951
1955-59 Atmospheric Conditions
Control run
** The timeframe for the present and past climatologies were selected as to reduce the influence of the El Niño Southern Oscillation (ENSO) and the North Atlantic Oscillation (NAO) on the Caribbean Early Rainfall Season (ERS) climate, as identified by previous studies (e.g., Malmgren et al. 1998, Taylor et al. 2002), and in accordance with historical LCLU changes
Model Results: Daily Cycle of Horizontal Surface Wind Vectors, PRESENT1 v PAST2
Model Results: Cloud Base Height Difference, 0.01 Mixing Ratio (g kg-1)
Model Results: Total Column Liquid Water Content Difference (g kg-1)
Model Results: ERS (3-Month) Accumulated Precipitation Difference (mm)
Model Results: ERS (3-Month) Accumulated Precipitation Difference (%)
SUMMARY • LCLU maps indicates a reduction in surface area covered by crops and agricultural lands in PR from 1951 to 2000, and an increase of urbanization and forests/shrub lands. • Historical global climate data shows an increase in average temperatures and a reduction in precipitation over the Caribbean basin during the 20th century. • The increased surface winds with a more easterly direction in the GW signal produced a shift in a convergence zone from the ridge of the mountain range (past) to the northern edge of the range (present). • This shift causes drastic changes in simulated total atmospheric column liquid water content and surface accumulated precipitation.
IPCC WG1 4th Assessment Report: Climate Change 2007, The Physical Science Basis
Christensen, J.H., et al., 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 [Solomon, S., et al. (eds.)]
•
•
•
• •
•
•
The Enriquillo and Sumatra lakes are saltwater lakes located in a rift valley that is a former marine strait created around 1 million years ago when the water level fell and the strait was filled in by river sediments Lake Enriquillo is in the Dominican Republic, it is the largest lake and lowest point in the Caribbean, and the lowest point on any ocean island Lake Sumatra is the largest lake in Haiti and the second largest lake of La Hispaniola, the brackish water lake is a Average Enriquillo and Sumatra Lakes Surface twin of the Enriquillo Lake Area 1984-2009 Lake size has increased around 49% from 2004 to 2009 Average precipitation throughout the island has increased by ~50 % increase between 1979 to 2009 In the region of the lake, average precipitation has increased by ~40% between 1979 to 2009 Average sea surface temperature around Hispaniola Island has increased by 0.4933˚F since 1982
Using Landsat images the surface area of the lake for past 30 years was calculated. The remote sensing measurements were analyzed in ArcGIS SOCIAL IMPACT • Flooding of 16 communities in two provinces • 10 000 affected farmers and families • Over 18 685 hectares of agricultural land flooded • Flooding and damages of over 1 000 properties
Why is the Surface Area of the Lakes Changing Dramatically? A Hydro-Meteorology Hypothesis Regional Climate Data, Barahona Station and Surrounding Water SST
Increased precipita2on
Reduc2on in evapora2on
Increase in orographic water produc2on
Orographic Lifting Schematic
Increase in Lake surface area
• Increased moisture in the lake area due to increased SSTs surrounding the lake basin • Increasing runoffs due to changes in use of surrounding land and increased precipitation • Increasing fresh water production in the area due to increased horizontal rain produced mainly by orographic cloud formation in the surrounding cloud montane forests A combination of these factors could lead to Total Lake Surface Area increase
A Hydro-Meteorology Hypothesis Tested with Atmospheric Modeling: Preliminary Results April 2004 (Lowest Point) and 1995 (Shrinking Period) Total surface precipitation and Total liquid water content between 700-1500 m
Modeling grids. Grid 3 showing model topography (c. int. 450 m)
Averaged surface wind (vectors) with vertical motions (contours) and Total liquid water content along cross-section at 18.25 N Lat.
Acknowledgements This research was partially funded by the NASA‐EPSCoR program of the University of Puerto Rico and by NOAA-CREST grant # NA06OAR4810162. The atmospheric model simulations were performed at the High Performance Computing Facilities of the University of Puerto Rico at Río Piedras. Thanks are due to Jeff Luvall, Ed Maurer, Bereket Lebassi, and Ana Picón for their contribution in carrying out this research to full term.
THANKS!
Daniel E. Comarazamy and Jorge E. Gonzalez NOAA-CREST, Department of Mechanical Engineering, The City College of New York, New York, NY
Outline INTRODUCTION
RELEVANT CLIMATE CHANGE STUDIES IN COASTAL TROPICAL REGIONS
OBJECTIVES METHODOLOGY
CASE OF SAN JUAN, PUERTO RICO
LCLU CHANGE
GLOBAL CLIMATE CHANGE
NUMERICAL EXPERIMENT MATRIX
RESULTS
CLIMATE IMPACTS OF LCLU CHANGES AND GLOCAL CLIMATE CHANGE IN COASTAL TROPICAL REGIONS
SUMMARY AND CONCLUSION
QUESTIONS AND COMMENTS
LCLU Changes Studies in Tropical Regions • Climate impact studies due to LCLU changes have been performed with combined observational and numerical components. • Velazquez et al. 2006 (San Juan, PR) - Urbanization • Lawton et al. 2001; Nair et al. 2003; Ray et al. 2006 (Monteverde, CR) - Deforestation • van der Molen, 2002; van der Molen et al. 2006 (Puerto Rico) - Deforestation and Reforestation • Some of the drawbacks of these studies is that the modeling is simplified and not all effects are included, analyzed, or separated.
Objectives An attempt to bridge the knowledge gap in the matter of the impact of LCLU changes in tropical coastal regions in a changing environment will be made by trying to answer the following questions: 1. What is the relative effect of historical LCLU changes on the climate of tropical coastal regions? 2. What is the relative climatic impact of global climate change in tropical coastal regions? 3. Under these conditions of LCLU and global climate change, what is the combined effect in tropical coastal regions?
Methodology / Numerical Experiments To answer the posed research questions, a series of numerical atmospheric simulations are proposed to separate the signals of LCLU change and global climate change. The Regional Atmospheric Modeling System (RAMS) will serve as the main research tool. General Model Configuration Grid 1 Grid 2 Grid 3 Δx = Δy
25km
5km
1km
σ-coordinate vertical
CPU time
Δσ = 30m near sfc until Δσ = 1km, model top at ~25km Approximately 5 to 6 days for a 30-day simulation Model grids with topography (contour interval: 150m)
Case of SJMA, Puerto Rico
Case of SJMA, Puerto Rico • Puerto Rico offers a great opportunity for LCLU change impact studies because: • The close proximity of the San Juan Metropolitan Area (SJMA), the Luquillo Experimental Forest (LEF), and the Central Mountain range • Evidence of combined global and local effects on regional climate • Historical LCLU practices (i.e., agriculture, urbanization, deforestation, reforestation) • The recently drafting and implementation of the Puerto Rico Land Use Plan
LCLU Specifications - Northeastern PR 1951
2000+ATLAS
IPCC WG1 4th Assessment Report: Climate Change 2007, The Physical Science Basis
Trenberth, K.E., et al., 2007: Observations: Surface and Atmospheric Climate Change. 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 [Solomon, S., et al. (eds.)]
IPCC WG1 4th Assessment Report: Climate Change 2007, The Physical Science Basis
Trenberth, K.E., et al., 2007: Observations: Surface and Atmospheric Climate Change. 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 [Solomon, S., et al. (eds.)]
Numerical Experiment Matrix
*
Run ID
LCLU
Driving Conditions**
Present1*
2000+ATLAS
2000-04 Atmospheric Conditions
Present2
2000+ATLAS
1955-59 Atmospheric Conditions
Past1
1951
2000-04 Atmospheric Conditions
Past2
1951
1955-59 Atmospheric Conditions
Control run
** The timeframe for the present and past climatologies were selected as to reduce the influence of the El Niño Southern Oscillation (ENSO) and the North Atlantic Oscillation (NAO) on the Caribbean Early Rainfall Season (ERS) climate, as identified by previous studies (e.g., Malmgren et al. 1998, Taylor et al. 2002), and in accordance with historical LCLU changes
Model Results: Daily Cycle of Horizontal Surface Wind Vectors, PRESENT1 v PAST2
Model Results: Cloud Base Height Difference, 0.01 Mixing Ratio (g kg-1)
Model Results: Total Column Liquid Water Content Difference (g kg-1)
Model Results: ERS (3-Month) Accumulated Precipitation Difference (mm)
Model Results: ERS (3-Month) Accumulated Precipitation Difference (%)
SUMMARY • LCLU maps indicates a reduction in surface area covered by crops and agricultural lands in PR from 1951 to 2000, and an increase of urbanization and forests/shrub lands. • Historical global climate data shows an increase in average temperatures and a reduction in precipitation over the Caribbean basin during the 20th century. • The increased surface winds with a more easterly direction in the GW signal produced a shift in a convergence zone from the ridge of the mountain range (past) to the northern edge of the range (present). • This shift causes drastic changes in simulated total atmospheric column liquid water content and surface accumulated precipitation.
IPCC WG1 4th Assessment Report: Climate Change 2007, The Physical Science Basis
Christensen, J.H., et al., 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 [Solomon, S., et al. (eds.)]
•
•
•
• •
•
•
The Enriquillo and Sumatra lakes are saltwater lakes located in a rift valley that is a former marine strait created around 1 million years ago when the water level fell and the strait was filled in by river sediments Lake Enriquillo is in the Dominican Republic, it is the largest lake and lowest point in the Caribbean, and the lowest point on any ocean island Lake Sumatra is the largest lake in Haiti and the second largest lake of La Hispaniola, the brackish water lake is a Average Enriquillo and Sumatra Lakes Surface twin of the Enriquillo Lake Area 1984-2009 Lake size has increased around 49% from 2004 to 2009 Average precipitation throughout the island has increased by ~50 % increase between 1979 to 2009 In the region of the lake, average precipitation has increased by ~40% between 1979 to 2009 Average sea surface temperature around Hispaniola Island has increased by 0.4933˚F since 1982
Using Landsat images the surface area of the lake for past 30 years was calculated. The remote sensing measurements were analyzed in ArcGIS SOCIAL IMPACT • Flooding of 16 communities in two provinces • 10 000 affected farmers and families • Over 18 685 hectares of agricultural land flooded • Flooding and damages of over 1 000 properties
Why is the Surface Area of the Lakes Changing Dramatically? A Hydro-Meteorology Hypothesis Regional Climate Data, Barahona Station and Surrounding Water SST
Increased precipita2on
Reduc2on in evapora2on
Increase in orographic water produc2on
Orographic Lifting Schematic
Increase in Lake surface area
• Increased moisture in the lake area due to increased SSTs surrounding the lake basin • Increasing runoffs due to changes in use of surrounding land and increased precipitation • Increasing fresh water production in the area due to increased horizontal rain produced mainly by orographic cloud formation in the surrounding cloud montane forests A combination of these factors could lead to Total Lake Surface Area increase
A Hydro-Meteorology Hypothesis Tested with Atmospheric Modeling: Preliminary Results April 2004 (Lowest Point) and 1995 (Shrinking Period) Total surface precipitation and Total liquid water content between 700-1500 m
Modeling grids. Grid 3 showing model topography (c. int. 450 m)
Averaged surface wind (vectors) with vertical motions (contours) and Total liquid water content along cross-section at 18.25 N Lat.
Acknowledgements This research was partially funded by the NASA‐EPSCoR program of the University of Puerto Rico and by NOAA-CREST grant # NA06OAR4810162. The atmospheric model simulations were performed at the High Performance Computing Facilities of the University of Puerto Rico at Río Piedras. Thanks are due to Jeff Luvall, Ed Maurer, Bereket Lebassi, and Ana Picón for their contribution in carrying out this research to full term.
THANKS!
