Climate Change Impacts and Mitigation

The following information was taken from the 2007 Intergovernmental Panel on Climate Change. Click here for the IPCC's "Climate Change 2007:Working Group I: The Physical Science Basis" webpage.I have linked each reference on this page directly to the specific page sited in the assessment report.

Regional Climate Change Projections
Projected Climate Change for the Caribbean is relatively interesting. This particular area is unique because it  shares features with both the Continental United States and with Central America.  As a result, the region may experience a change in climate that is very different from the popularly publicized global warming woes (such as extensive flooding). Most scientific models predict that there will be a decrease in precipitation for the entire Caribbean region (IPPC, 2007). A 2006 study found "a modest but statistically significant summer drying trend over recent decades in the Caribbean in several observational data sets" (IPPC, 2007). This is a particularly disturbing trend for nations like Haiti that are heavily agricultural.

Image taken from the IPCC's "Climate Change 2007:Working Group I: The Physical Science Basis." These are images of change in precipitation for the region calculated for the region. 

While scientists have noticed an obvious sea level rise at about 30S for the region, they are uncertain about making projections for future sea level changes (IPPC, 2007). Therefore, it is difficult to make an educated guess how much the shorelines for the Caribbean islands will be altered from rising sea levels. Also, scientists are uncertain "about the changes in frequency and intensity of tropical cyclones on a regional basis than for temperature and precipitation changes" (IPPC, 2007). Depending on how warm the ocean becomes and if the region for hurricane formation changes in the future, Haiti could face more or less hurricanes in the future.

From United Nations Photo on flikr. Here, Jordanian UN soldiers help orphans in the aftermath of hurricane Ike. Scientists are uncertain if more hurricanes make landfall on Hispaniola due to Climate Change. 

 Specific Climate Impacts:
(For this particular section, I used this page about specific climate impacts for small islands from IPCC 2007 Report’s Working Group II:  Impacts, Adaptation, and Vulnerability: Summary for policymakers. This section of the report did not feature specific page of Climate Change impacts for the Caribbean region.)

Overall, small islands-- whether in the Caribbean or in the North Sea-- will be heavily impacted from Global Climate Change, such as "sea-level rise and extreme events." Island economies are expected to decline due to the "[d]eterioration in coastal conditions;" industries that will be effected are fishing and tourism. "Sea-level rise is expected to exacerbate inundation, storm surge, erosion and other coastal hazards, thus threatening vital infrastructure, settlements and facilities that support the livelihood of island communities."  Islands in the Pacific and Caribbean are projected to face water shortages "during low-rainfall periods." An island's ecosystem "particularly [...] mid- and high-latitude islands" will be altered due to "increased invasion by non-native species" influenced by increasing temperatures. (IPCC, 2007)  

Detailed Look at Future Climate: 

Scientists estimate that there is a moderate chance that the occurrence of  infectious disease will  increase on small islands due to climate change. Outbreaks, such as the Haitian malaria outbreak in 2006, will increase.  "Other climate-sensitive diseases of concern to small islands include diarrhoeal diseases, heat stress, skin diseases, acute respiratory infections and asthma. The observed increasing incidence of many of these diseases in small islands is attributable to a combination of factors, including poor public health practices, inadequate infrastructure, poor waste management practices, increasing global travel, and changing climatic conditions" (IPCC, 2007). 

Photo by "audra k." on flikr. An informative poster in creole about preventing malaria. Cases of malaria in Haiti may increase due to climate change. 

As previously stated, the Caribbean region is expected to experience water shortages. "Under all Special Report on Emissions Scenarios (SRES) scenarios, reduced rainfall in summer is projected for this region, so that it is unlikely that demand would be met during low rainfall periods. Increased rainfall in winter is unlikely to compensate, due to lack of storage and high runoff during storms."  In addition to water loss, "[s]ea-level rise, inundation, seawater intrusion into freshwater lenses, [and] soil salinisation [...] are very likely to adversely impact coastal agriculture." Other possible outcomes for the future climate are: increased likelihood of sea-level rise and "vulnerability" to natural disasters, reduction in the size of islands (affecting infrastructure), decline of local fisheries, loss of native species,  and negative effects on the tourism industry. (IPCC, 2007)

Most Interesting Threat:

 Personally, I find that the most interesting threat to the Caribbean is a decrease in tourism. I enjoyed taking Macro and Micro economic courses in university, and believe that trade is an important tool for improving the welfare of mankind.  Therefore, I understand that an decline in a nation's economy will lead to a decrease in  welfare for all citizens. "Small economies are generally more exposed to external shocks, such as extreme events and climate change, than larger countries, because many of them rely on one or a few economic activities such as tourism or fisheries"(IPPC, 2007). In general, islands in the Caribbean rely heavily on tourism, unlike BRIC or North American economies. Caribbean islands are well known as a popular travel destination, often portrayed as sunny tropical locales with beautiful beaches. These beaches, however, are expected to change or disappear due to sea-level rise. "Shortage of water and increased risk of vector-borne diseases may steer tourists away from small islands, while warmer climates in the higher-latitude countries may also result in a reduction in the number of people who want to visit small islands in the tropical and sub-tropical regions" (IPPC, 2007). With a decrease in tourism,  small island nations could experience national economic crises. This is, however, a bit of an overstatement. If island governments are wise, they could potentially soften the potential economic blow by various means tailored to their own economy (IPPC, 2007). 

Severe Weather in Haiti

The following post will discuss tornadoes and hurricanes. Tornado and hurricane formation and frequency on the Continental US will be compared to Haiti's tornado and hurricane frequency.

 Tornadoes: 

    Tornadoes are created during intense thunderstorms. Tornadoes are air rotating rapidly around a narrow region of low pressure. This center of low pressure can be as low as 900mb. A tornado's wind speed can be between 70-300 mph. There a three steps to tornado development. The first step involves forming a rotating body of air at the surface (vortex tube). Vertical wind shear helps the vortex tube to start spinning. The change in wind speeds with increasing height helps to keep the storm strong. During the next step, the horizontal vortex tube is lifted off of the ground by a thunderstorm's updraft. (The updraft lifts the rotating column of air similar to human lifting a cat.) The rotating column of air is pulled into the thunderstorm. A mesocyclone develops in the updraft of the thunderstorm once the rotating column of air is vertical. During the third step, a the rotating vertical column of air's circumference contracts, increasing wind speeds. The vertical column of air then descends from the mesocyclone's wall cloud. The mesocyclone becomes a thunderstorm once the vertical column of air touches the ground (Small, J.; Lecture 18). 

    In the US, tornadoes can travel in any direction. However, many tornadoes travel southwest to northeast, or from west to east. Robert Edwards of the Storm Prediction Center at NOAA, claims that tornadoes tend to travel in a dominant direction due to "an increased frequency of certain tornado-producing weather patterns (say, hurricanes in south Texas, or northwest-flow weather systems in the upper Midwest" (The Online Tornado FAQ, NOAA).

    While tornadoes are common on the Continental Untied States, they are a rarity in the Caribbean. As of 2000, no known tornadoes have occurred on the island of Hispaniola. (However, tornadoes have occurred on other islands of the Caribbean, such as Cuba.) (The Tornado Project). According to NOAA, the yearly average number of tornadoes in the US is over 1,000 (NOAA), while the  yearly average number of hurricanes in Haiti is zero (The Tornado Project).  

A map of Global tornado occurrences (Wikipedia).

        Above is a global map of tornado occurrences, featuring areas denoting tornado "hot spots" shaded in orange. Hispaniola and the entire Caribbean are not shaded, insinuating that the region is not a tornado "hot spot." Therefore, the region rarely, if ever, experiences tornadoes. Almost the entire Continental United States, however, is shaded orange. According to a graph released by NOAA, the US Annual Tornado Count has been steadily increasing. This might, however, not be true, as technology has improved to detect tornadogenesis has dramatically improved over the past 30 years. Prior to such advancements, scientists could not possibly know about every single tornado that hit the US (including uninhabited areas). The increase in number of observed tornadoes may be due to the fact that scientists can now detect, track, and study tornadoes in more detail now than they previously could.

Hurricanes:

   Hurricanes need three "ingredients" in order to form: warm ocean temperatures greater than 27°C (>80°F), the Coriolis effect, and a deep layer of ocean water (about 200 m in depth). Therefore, the prime areas for hurricane formation occur between 20 and 5 N/S, respectively. 

  Hurricanes are called by different names in different formation regions. In the Atlantic and Pacific (1 and 2 on the map below), these storms are called hurricanes. In the Indian Ocean and in the areas surrounding Australia and La Réunion (4,5,6,7 on the map), these kinds of storms are called cyclones. Typhoons form off of China's coast (3, on the map). The term used internationally for hurricanes is Tropical Cyclone (Small, J.; Lecture 20). 

A map showing the formation regions of tropical cyclones, with labeled RSMCs (Wikipedia).

An exhaustive map showing tropical cyclone paths. Note how tropical cyclones in the Northern Hemisphere tend to curve to the left upward, while tropical cyclones in the Southern Hemisphere curve to the opposite way. (Wikipedia)

      In the United States, hurricanes tend to travel Northward up the East Coast. Tropical storms in the Atlantic tend to develop off of the Western Coast of Africa, travel to the Caribbean, and turn up the US Atlantic Coast (see the above map for marked paths of tropical cyclone storms). Hurricanes tend to travel up the Atlantic Coast because the Gulf Stream (aka North Atlantic Drift) flows upward from the Gulf of Mexico along the East Coast. Hurricanes, fueled by the warm water beneath, are directed from above by the West-Easterly flow of the region's Jet Streams and Westerlies up the East Coast (Small, J.; Lecture 20).

    Like the US East Coast, hurricanes have impacted Haiti in the past, and will affect Haiti in the future. (Click here to learn more about how hurricanes impact the well-being of Haitian citizens.) Many hurricanes travel over or by Haiti before going north and making landfall on the Continental United States (please see the exhaustive map of tropical cyclone paths above). The average number of hurricanes that appear each year in the Atlantic basin is 6.3. Interestingly, the average number of hurricanes that make landfall on the Continental US each year is 1.7 (Hurricane Research Division, NOAA), while the average annual number of hurricanes that make landfall on Hispaniola is one (Klose, C.).