This document summarizes a study on the contribution of tropical cyclones to the rainfall climatology of Puerto Rico. It analyzes rainfall data from 1970-2010 from 32 weather stations on the island and tracks of 86 tropical cyclones that passed within 500km of Puerto Rico. The main findings are:
1) Tropical cyclones can contribute up to 15-34% of total rainfall during the hurricane season, with the highest contributions in August-September in the east and south.
2) Contributions decrease from east to west, with the east and south seeing more than 10% of rainfall from tropical cyclones in some months.
3) June has the lowest contributions around 1% while July sees
Workshop on Operationalizing the Regional Collaborative Platform to Address ‘Water Consumption, Water Productivity and Drought Management’ in Agriculture, 27 - 29 October 2015, Cairo, Egypt
Workshop on Operationalizing the Regional Collaborative Platform to Address ‘Water Consumption, Water Productivity and Drought Management’ in Agriculture, 27 - 29 October 2015, Cairo, Egypt
This presentation is the part of 12-day (28 January–8 February 2019) training workshop on “Multi-scale Integrated River Basin Management (IRBM) from the Hindu Kush Himalayan Perspective” organized by the Strengthening Water Resources Management in Afghanistan (SWaRMA) Initiative of the International Centre for Integrated Mountain Development (ICIMOD), and targeted at participants from Afghanistan.
Paul Barton (of University of Massachusetts Amherst), presented at the Adapting Forested Watersheds to Climate Change Workshop, at Antioch University New England, Keene, NH on April 4-5, 2017. The workshop was hosted by the Northern Institute of Applied Climate Science (NIACS), USDA Climate Hubs, and Trout Unlimited.
Details at www.forestadaptation.org/water.
Maintaining proper preparedness for GLOF hazards and drawing attention to the task of mitigation are
important goals, necessitating exploration of past cases of outbursts. The frequency of GLOF occurrences is
still unknown, because major outbursts which cause significant damage downstream are rare and records have
been kept on them for only the past several decades. We have to collect as much data on past outburst events
as possible, including unpublished and previously unknown incidents. As is obvious in the traces of known
GLOFs, an outburst event leaves typical topographical and sedimentological features, i.e., 1) V-shaped
trenches, 2) huge debris fan depositions and 3) subsequent devastated river beds. Hence, these features can be
used as proof of past outburst events. We describe the 2009 Tshojo flood as the most recent case of a GLOF in
the Bhutan Himalayas. The flood, which was initiated by dam leakage and water splashing on the surface
from en-/sub-glacial passage, was a potentially dangerous hazard. Attention to such outburst events from
invisible sources will be required in the future.
Hurricane Threat and Risk Analysis in Rhode Islandriseagrant
Hurricane Threat and Risk Analysis in Rhode Island presented at the July 24, 2014 Beach Special Area Management Plan Stakeholder meeting.
Dr. Isaac Ginis, URI Graduate School of Oceanography
View the video here: http://new.livestream.com/universityofrhodeisland/StormRecoveryRI
Seismic Imaging of the western Hellenic Subduction zoneFrederick Pearce
This is a presentation I gave at the University of Washington in Dec 2011 that gives an overview of my Ph.D thesis work at a relatively early stage (includes updated references). It lays out the objective of my thesis, and presents three different "views" of the Hellenic subduction zone, using three complimentary seismic imaging methods: 1) Teleseismic migration, 2) Receiver functions, and 3) Local tomography.
This presentation is the part of 12-day (28 January–8 February 2019) training workshop on “Multi-scale Integrated River Basin Management (IRBM) from the Hindu Kush Himalayan Perspective” organized by the Strengthening Water Resources Management in Afghanistan (SWaRMA) Initiative of the International Centre for Integrated Mountain Development (ICIMOD), and targeted at participants from Afghanistan.
Paul Barton (of University of Massachusetts Amherst), presented at the Adapting Forested Watersheds to Climate Change Workshop, at Antioch University New England, Keene, NH on April 4-5, 2017. The workshop was hosted by the Northern Institute of Applied Climate Science (NIACS), USDA Climate Hubs, and Trout Unlimited.
Details at www.forestadaptation.org/water.
Maintaining proper preparedness for GLOF hazards and drawing attention to the task of mitigation are
important goals, necessitating exploration of past cases of outbursts. The frequency of GLOF occurrences is
still unknown, because major outbursts which cause significant damage downstream are rare and records have
been kept on them for only the past several decades. We have to collect as much data on past outburst events
as possible, including unpublished and previously unknown incidents. As is obvious in the traces of known
GLOFs, an outburst event leaves typical topographical and sedimentological features, i.e., 1) V-shaped
trenches, 2) huge debris fan depositions and 3) subsequent devastated river beds. Hence, these features can be
used as proof of past outburst events. We describe the 2009 Tshojo flood as the most recent case of a GLOF in
the Bhutan Himalayas. The flood, which was initiated by dam leakage and water splashing on the surface
from en-/sub-glacial passage, was a potentially dangerous hazard. Attention to such outburst events from
invisible sources will be required in the future.
Hurricane Threat and Risk Analysis in Rhode Islandriseagrant
Hurricane Threat and Risk Analysis in Rhode Island presented at the July 24, 2014 Beach Special Area Management Plan Stakeholder meeting.
Dr. Isaac Ginis, URI Graduate School of Oceanography
View the video here: http://new.livestream.com/universityofrhodeisland/StormRecoveryRI
Seismic Imaging of the western Hellenic Subduction zoneFrederick Pearce
This is a presentation I gave at the University of Washington in Dec 2011 that gives an overview of my Ph.D thesis work at a relatively early stage (includes updated references). It lays out the objective of my thesis, and presents three different "views" of the Hellenic subduction zone, using three complimentary seismic imaging methods: 1) Teleseismic migration, 2) Receiver functions, and 3) Local tomography.
Presentation held by Jasper Batureine Mwesigwa from IGAD Climate Prediction and Applications Centre (ICPAC), at the learning event The Community Based Adaptation and Resilience in East and Southern Africa’s Drylands, held in Addis Abeba, Ethiopia by Care International Adaptation Learning Program for Africa (ALP), The CGIAR research program on Climate change, Agriculture and Food Security (CCAFS) and African Insect Science for Food and Health (ICIPE)
Impact of Climate Modes such as El Nino on Australian RainfallAlexander Pui
The relationship between seasonal aggregate rainfall and large scale climate modes, particularly the El Niño-Southern Oscillation (ENSO), has been the subject of a significant and on-going research effort. However, relatively little is known about how the character of individual rainfall events varies as a function of each of these climate modes. This study investigates the change in rainfall occurrence, intensity, and storm inter-event time at both daily and sub-daily timescales in East Australia, as a function of indices for ENSO, the Indian Ocean Dipole (IOD), and the Southern Annular Mode (SAM), with a focus on the cool season months. Long record data sets have been used to sample large variety of climate events for better statistical significance. Results using both the daily and sub-daily rainfall data sets consistently show that it is the occurrence of rainfall events, rather than the average intensity of rainfall during the events, which is most strongly influenced by each of the climate modes. This is shown to be most likely associated with changes to the time between wet spells. Furthermore, it is found that despite the recent attention in the research literature on other climate modes, ENSO remains the leading driver of rainfall variability over East Australia, particularly further inland during the winter and spring seasons.
Presented by Vladimir Smakhtin at the National Workshop on “Use of Space Based Information for Disaster Management” Colombo, Sri Lanka, November 17, 2014.
1. José J. Hernández Ayala
Department of Geography
University of Florida
Contribution of Tropical Cyclones to
the Rainfall Climatology of
Puerto Rico
2. Introduction
• Important Questions
What is the spatio-temporal distribution of rainfall contributed by TCs?
How Teleconnections such as ENSO and the NAO affect this contribution?
How would a changing climate affect the contribution of rainfall from TCs?
(Knight and Davis 2007; Knight and Davis 2009; Sheperd et al., 2007)
• Rainfall arising from tropical cyclones (TC) can be an important water source for
agriculture and other applications over subtropical and tropical regions (Rodgers et
al., 2001).
6. Tropical Cyclones and Puerto Rico
• Puerto Rico is subject to frequent and severe impacts
from Hurricanes (Dunn and Miller 1964, Simpson &
Riehl 1981, Diaz & Pulwarty 1997).
• The frequency with which a tropical cyclone passes
directly over Puerto Rico is small (Scatena and Larsen,
1991).
• A comprehensive study of hurricanes in P.R based on
meteorological principles and the historical record is
lacking (Boose, Serrano &Foster 2004).
• Storm rainfall totals of 500 mm are common for
hurricanes in Puerto Rico (Riehl, 1979).
9. Problem Statement
• Understand the contribution of TCs to the rainfall climatology of
the island.
• Do TCs have different contributions to the rainfall climatology of the
island in different regions?
• Do some hurricane season month’s exhibit higher or lower rainfall
contributions from storms?
10. Hypotheses
• Rainfall associated from TCs is highly concentrated in the eastern portion of
the island where El Yunque National rain forest is located.
• A general decrease in storm precipitation is observed as you move from the
eastern to the western region of the island.
• TCs will tend to contribute more to the rainfall climatology of stations in the
eastern and southern regions of the island especially during the peak hurricane
season months of August, September and October.
• The south will also have high rainfall contribution percentages since this
region is the driest of the island, and for that reason any precipitation
generating process that impacts the area has an important contribution to its
rainfall climatology.
11. Data
• Six-hourly TC positions were obtained from the International Best Track
Archive for Climate Stewardship (IBTrACS) (Knapp et al., 2010) for the
years 1970 through 2010.
• Daily and monthly rainfall totals were obtained from the National
Climatic Data Center (NCDC), for 32 weather stations located on the main
island of Puerto Rico for the period of 1970-2010.
13. TC Tracks
• 86 TCs were identified as
the ones that passed within
a 500 km around the island.
• Most move east to west,
only a few events move west
to east.
14. Methods
• The contribution of rainfall associated with TCs will be estimated for each
month of the hurricane season (June-November) by calculating a
percentage between monthly total and daily rainfall for all 86 TCs over the
1970-2010 period.
• After the percentage for each hurricane season month is calculated for all
weather stations the next step will be to map the percentages for each
month.
• Natural Neighbor and Ordinary kriging interpolated surfaces for all
hurricane season months were generated to identify spatial patterns of
high/low contribution percentages.
15. Results
Hurricane Season Months (J-N)
NN Season OK Season
0.07
5.26
16.61
19.50
7.90
2.80
8.69
0.00
5.00
10.00
15.00
20.00
25.00
June July August September October November Season
MeanPercentage(%)
Hurricane Season Monts
19. Conclusions
• TCs contribute as much as 15% of the rainfall during the entire Hurricane
season in some portions of the south.
• June has the lowest contribution while July shows that storms contribute as
much as 11% in the central south.
• August and September have the highest contributions of rainfall associated
with TCs, with some areas in the east and south exhibiting percentages of 26%
and 34%.
• October shows TC rainfall contributions of 12-15% in the east and south while
November exhibits lower contributions of 5-7% in the southeast.
• All Hurricane season months show a decreasing trend in contribution from east
to west.
20. Limitations
• Limited by the use of only 32 stations with data for the 1970-2010
period.
• There are some areas of the island that are not well represented.
• Not having sufficient observations in the central mountains is a
huge limitation since topography plays a big role when it comes to
understanding rainfall patterns in the island.
21. Future Work
• Understand TC rainfall contribution variability, connections with
ENSO, AMO, NAO?
• Understand changes in TC rainfall contribution and its connections
with climate change?