Climate Change Impacts

Regional Climate Projections

In the 21st century, El Salvador and more broadly the entire Latin American region is likely to go through a number of climate changes. During this current century, all of Central and South America is likely to warm.  The precipitation in Central America is likely to decrease and the region’s relatively dry springs will become even drier.  Tropical cyclones may have a greater impact on the region, for there may be a change in the path and intensity of hurricanes.  This change in hurricane path/intensity will have the ability to cause damage in a number of different regions and will have an effect on weather in Central America.  

Impacts, Adaptions, and Vulnerabilities for El Salvador and the region of Central America

Central America is at a high risk for forest loss and for less runoff.  Central America and the country of El Salvador are likely to have increased vulnerability to extreme events.  According to the IPPC's 2007 Climate Change report, “almost 13.9% of the Latin American population (71.5 million people) has no access to a safe water supply” (13.4.3).  To worsen the situation, water availability and hydroelectric generation will be reduced because of a steady decline in the amount of glaciers.  Current vulnerabilities will increase because of growing demand of water due to the ever-growing populations of Latin American countries.  “By the end of the 21st century, the projected mean warming for Latin America ranges from 1 to 4°C or from 2 to 6°C [. . .] and the frequency of weather and climate extremes is very likely to increase” (13.7).

Climate Change: Depletion of Water Resources in Latin America

In Central America, there has been a declining trend in rainfall amounts within the last decade.  Also, the region has experienced a 1 C temperature increase that has in turn led to the acceleration of glacier retreat (Executive Summary).  “By the 2020s, the net increase in the number of people experiencing water stress due to climate change is likely to be between 7 and 77 million (medium confidence).”  Although some countries have tried to adapt to climate change through the conservation of ecosystems, early warning systems and risk management for both agriculture and drought (to name a few), a lack of basic information and proper political/technological systems has set the Latin American region back.

Water Scarcity: The Biggest Threat to Latin America 

The most interesting threat to El Salvador is related to its diminishing water supply.  The Central American region, and Latin America in general currently has a very limited access to a clean water supply.  With increasing populations and changing weather conditions, those living in Central America will be without the necessary water that is needed to survive.  I chose the water dilemma as most interesting because the threat is both real and significant and it has the ability to affect tens of millions of people.  I care about the health and safety of human beings and because of that, I show a great interest in the topic of water scarcity.  The Latin American region needs to be properly educated about the impact that climate change will have on the continent.  It needs leaders that are capable of implementing effective strategies on how to cope with the ever-decreasing drinkable water supply. 

Illustrating the Impact Climate Change has had on Latin America and the rest of the World

(IPPC, 13.7, Figure 13.5)

Temperatures in the Norther Hemisphere have increased exponentially over the last century

(http://gwglaciers.tripod.com/sitebuildercontent/sitebuilderpictures/meltingglacier1.jpg)
Global warming has caused glaciers to melt at an astounded rate.  

Severe Weather in El Salvador

Tornadoes

There are three steps in the formation of the tornado.  In step one, vertical wind sheer causes a rotating body of air to form at the ground.  Next, horizontal rotating air is lifted off the ground by the updraft of a thunderstorm.  Once this horizontal rotating air mass is lifted vertically it is called a mesocyclone.  In the third and final step, the mesocyclone is fully developed in the updraft of the thunderstorm.  A funnel cloud is then formed from a narrow, fast rotating structure in the wall cloud; when this funnel cloud touches the ground it is referred to as a tornado.

In the United States, tornadoes usually travel southwest to northeast.  This is due to the fact that tornadoes form during intense thunderstorms, and thunderstorms normally travel in the southwest to northeast direction.  Most intense thunderstorms, and in turn tornadoes, develop in the Central Plain region ("Tornado Alley") because warm, humid air surface is overlain by cooler, drier air which produces an unstable atmosphere.  This unstable atmosphere helps to form large supercell thunderstorms and as a result, tornadoes as well.  

Tornadoes have occurred in El Salvador, but they are an extremely rare occurrence.  Tornadoes are a rare occurrence in El Salvador because of the country’s geographic location.  So many tornadoes occur in the central part of the United States because of its proximity to the Rockies (which forces dry line formation) and the Gulf of Mexico (which supplies low-level moisture).  El Salvador’s warm, tropical climate is not conducive for thunderstorm and tornado formation.  As a result, an average of 0 tornadoes occur in El Salvador p/year (http://www.ustornadoes.com/2013/07/25/from-domestic-to-international-tornadoes-around-the-world/ ) compared to the 1,523 tornadoes that occur in the US each year (http://www.ncdc.noaa.gov/oa/climate/severeweather/tornadoes.html) 

Add http://www1.ncdc.noaa.gov/pub/data/cmb/images/tornado/2010/annual/2010annual_torncount.png

According to the above graph, tornado occurrences have seemingly increased over time.  However, this might not necessarily be true because improved technology (Doppler radar, greater attention to tornado reporting, etc.) has allowed meteorologists and storm chasers the ability to record more storms than in previous years.  The above visual on "U.S. Annual Tornado Count" only takes into account the amount of tornadoes that are reported on a year-to-year basis.  As a result, the same amount of tornadoes may occur from year-to-year, but more may have been recorded in recent years.  Increased National Doppler radar coverage, increasing populations and greater attention to tornado reporting has all led to a rise in the number of reported tornadoes in the past decade.  As a result, these factors have created a misleading appearance of a growing trend in tornado frequency in the U.S.

Worldwide Tornado Frequency

http://web.gccaz.edu/~lnewman/gph111/topic_units/thunder_hurr/07_36.jpg

Hurricanes

In order for a hurricane to form, there needs to be warm ocean temperature (higher than 80F), a deep warm ocean layer more than 200 meters in depth, and the Coriolis effect is needed to initiate spinning (most hurricanes develop between 5 and 20 degrees latitude).  

The main hurricane formation regions occur in the Atlantic and East Pacific (where they are called hurricanes), in the Indian Ocean near Australia (where they are called Cyclones), and off the Coast of China and Indonesia (where they are called Typhoons).  

Hurricane Formation Regions

http://weatherdork.weebly.com/1/category/weather/1.html 

In the United States, hurricanes generally travel from east to west, but travel northward when they hit land.  Hurricanes form over the warm, tropical North Pacific and North Atlantic and are steered westward or northwestward by easterly winds.  These trade winds cause hurricanes to move east to west.  

Hurricanes do occur in El Salvador and travel in the same east to west direction that they do in North America.  El Salvador is located in Central America, nearby to both the Pacific Ocean and Caribbean Sea.   El Salvador is geographically located between 13 and 15 degrees N and between 88 and 90 degrees W.  Hurricanes form in the warm Caribbean Sea (to the east of El Salvador) and are pushed westward by trade winds.  The country's unique location (directly west of the Caribbean Sea) makes it fairly immune to the brunt of storms.  The trade winds rarely blow storms far enough west to make landfall in El Salvador.  Only 16 total hurricanes/tropical storms (less than 1 storm p/year) have ever made landfall in the country compared to the 1.78 hurricanes that make landfall in the United States p/year (http://www.aoml.noaa.gov/hrd/tcfaq/E17.html).  

Conclusion

El Salvador’s location in Central America and its warm, tropical climate contribute to its lack of tornado occurrence and in the sparse amount of hurricanes that occur.  El Salvador’s warm climate is not conducive for tornado formation, whereas in the central part of the United States, warm, moist air from the Gulf of Mexico and cool, dry air from the Rockies aid tornado formation. 

El Salvador is located to the west of the warm Caribbean Sea and is affected by hurricanes or tropical storms from time-to-time.  El Salvador is located in a unique region because the Caribbean Sea is located directly to the west of the country and trade winds rarely push storms westward enough to affect El Salvador.  As a result, El Salvador very rarely receives the brunt of the storm, but rather the outermost parts of it.  While hurricanes frequently pass by El Salvador, they do make landfall in the North American continent.  The United States’ location in the mid latitudes affects the generous amount of hurricanes that occur in the US.