Thursday, May 1, 2014

Global Climate Change and its Impact on the East Mountains


                 As the Earth cycles through its natural patterns, the sun’s rays reach the planet in different ways.  No matter where in the cycle the Earth is, radiation from the sun enters the Earth’s atmosphere in short waves and exits as long wave radiation.  Radiation is either reflected or absorbed by the surface of the Earth depending on the materials it encounters (i.e: air, land, or water).  Albedo is the reflectivity of materials to the sun’s rays.  High albedo means high reflectivity which means little heat absorption.  For example, the albedo of clouds is very high because clouds are light in color and made of water generally resistant to short wave absorption.  Clouds reflect radiation from both sides.  They reflect radiation from the sun back into space but also reflect radiation from the Earth back to the surface.  Albedo impacts temperatures on Earth by affecting the amount of radiation within the system.  New Mexico often doesn’t have the protection of clouds so temperatures vary greatly from day to night.



                Each of the life zones of the East Mountains differ in temperature partly because of elevation and latitude but also because of albedo.  In the life zones higher up on the mountainside, the concentration of dark green trees would lead one to expect higher temperatures, however very little sunlight reaches the forest floor and so it is not being absorbed by the Earth.  In the winter, this life zone is often covered in snow which has a high albedo and leads to overall cooling in the area.  The life zone just below that often has cloud cover in the morning preventing heat radiation from reaching the Earth but then loses its cloud cover at night allowing the Earth to cool off which leads to higher temperatures than the first zone but lower temperatures than the life zones below.  The transitional life zone has trees that are less dense, allowing more sunlight to penetrate and reach the Earth.  This life zone rarely has high winds cooling off the area making it warmer than the top of the mountain.  The lowest life zone has sparse tree cover but also has an abundance of grasses with low albedo.  Heat is usually absorbed during the day resulting in high temperatures in the afternoon but heat is also lost while the sun is set because there are not usually clouds in the atmosphere to hold the heat in. 



 

                The long wave radiation that the Earth emits is generally stopped by gases in the atmosphere.  Greenhouse gases are the gases in the atmosphere whose material compound keep heat in and create the greenhouse effect.  The greenhouse effect is when radiation is absorbed by compounds in the atmosphere and reiterated all over the Earth, resulting in an overall increase in temperature.  Contrary to popular belief, the greenhouse effect is necessary and natural.  Without it, the Earth would cool uncontrollably at night and make most environments inhospitable.  However, the greenhouse effect is often coupled with global warming as a root cause of temperature increases today that are outside cyclical circumstances.  CO2 or Carbon Dioxide is the most disputed greenhouse gas.  CO2 is a compound in the atmosphere that “loves” long wave radiation.  Air pollution from humans contributes greatly to a rise in CO2 concentration in the atmosphere and therefore an increase in the greenhouse effect.  For example, burning coal for energy releases carbon into the air and contributes to higher temperatures. 

                Many people argue that CO2 concentration has nothing to do with the greenhouse effect. But others argue that the composition of the atmosphere is important. Evidence on Earth suggests that CO2 concentration is linked directly to temperature.  When CO2 levels rise so does temperature.  Rising temperatures on a global scale is called global warming.

                Global warming is a concept of increasing temperatures and is impacted by cyclical events such as Milakovitch Cycles as well as the compounds in the Earth’s atmosphere and the effect of albedo.  Sometimes circumstances synchronize to create constant warming or cooling conditions over thousands of years.  However, human activities contribute to the out of control global temperature increase that is happening today.  In today’s circumstances, carbon levels are in fact rising naturally.  However, carbon levels that sustain human life in the past have never risen above 280 parts per million.  Today carbon levels are at about 390.1 parts per million.  This shows that the carbon concentration in the atmosphere is not entirely natural.  Temperatures are also rising resulting in overall global warming.     



                Global warming can have serious repercussions on the global environment such as melting ice caps, global sea rising, and plant and animal species going extinct because of changing conditions.  Species loss all over the world indicate very fast climate change.  Species today are going extinct at nearly one thousand times the natural rate.  This is evidence to further the claim that humans are responsible for the rise in global temperatures.  As countries go through industrial revolutions, they increase their carbon emissions quickly.  Not only are humans emitting carbon into the air, they’re also inhibiting the ability of the Earth to filter out that carbon.  A carbon sink is a location or material that contains carbon dioxide and effectively keeps it from being in the atmosphere.  For example, plants take in CO2 and release O2 into the air, incorporating the carbon into their tissue.  Rain forests are enormous carbon sinks.  Human activity and the deforestation of many rain forests, destroys natural solutions to carbon pollution and exacerbates the problem. 

                Overall, a combination of human activity and Milankovitch cycles have caused carbon levels to rise which has led to a rise in global temperatures.  This all affects the life zones in the East Mountains.  An example of this is the bark beetle problem.  Constant warm winters have allowed the bark beetle population to grow unchecked by freezing temperatures.  As a result, the trees in the area can no longer compensate for the large population of beetles.  This weakens the trees and increases the likelihood of forest fires which destroys natural habitats for animals.  Natural global warming is "ok" but when it is out of control, as we can see with local examples, it is up to people to intervene.  If humans change their habits, the problem can still be solved.

Interesting Examples of Cloud Formations

Altocumulus Clouds Above the East Mountains

Cumulus and Stratocumulus Clouds

Cumulonimbus Clouds due to Orographic Uplift

Cirrostratus Halo, Cirrostratus and Cumulus Clouds

Stratus Clouds Near the Mountains
 
Cumulus Clouds due to Orographic Uplift

Monday, April 7, 2014

Weather Systems and Patterns




What types of weather systems does the East Mountain region experience? What global circulation patterns influence those weather systems?

An air mass is a large body of air having a more or less uniform temperature and moisture content covering large regions of the Earth. The different types of air masses are defined and referred to usually based on temperature and moisture content:

Temperature
Tropical – (T) generally hot
Polar – (P) generally cooler
Arctic – (A) generally very cold

Moisture content
Maritime – (m) wet
Continental – (c) dry

The East Mountains, and a good part of New Mexico is typically under a Continental Polar air mass in the winter and a Continental Tropical air mass in the summer. This means that New Mexico is often dry and cold in the winter and dry and hot in the summer. Any variations in the air mass above the East Mountains is due to patterns of global circulation of air in the atmosphere.

One such global circulation pattern is due to the Jet Stream. The Jet Stream occurs when a sharp temperature gradient from a polar front causes a steep pressure gradient and air is under strong pressure gradient force, this causes air to move fast at high altitudes over the. Jet streams usually occur 9 to 12km above sea level. Rossby waves are essentially wiggles in the Jet stream, the top part of the wave is a ridge and the bottom is a trough.

The Polar Jet Stream Across the United States
Generally, where a ridge turns into a trough there is an area of high pressure and where a trough turns into a ridge there is an area of low pressure which is usually indicative of storms.

Because New Mexico is located continentally and no large bodies of water exist in direct proximity to the land, it relies mostly on systems developed and moved by the Jet Stream for moisture containing air that can lead to precipitation and larger storms.
Jet Stream Over New Mexico

 Another factor influencing storm systems in the East Mountains are the Al Niño and La Niña oscillating patterns across the Pacific Ocean. If you have ever heard a weather man say that it is going to be an El Niño winter, you know to expect more precipitation in New Mexico. But what is an El Niño?

Walker circulation is the circulation of air in the atmosphere that is a result of the complex interaction between heating in the atmosphere and heating of the ocean and ocean currents. El Niño and La Niña conditions are caused directly by Walker circulation being either stronger or weaker than usual.

An El Niño is what occurs when the Walker circulation cell weakens and warm pacific waters that are usually blown away from the western coast of the US are allowed to slosh back resulting in cooler than normal temperatures near the Philippines and abnormally warm moist air near the coast of California.

A La Niña is what occurs when the Walker cell is stronger than normal and warm pacific waters are moved even farther than usual resulting in abnormally warm temperatures in the Philippines and abnormally cold and dry weather along the coast of California.
Heat Signatures of the Two Patterns



Tuesday, March 25, 2014

More Weather and Climate Data for the East Mountains

What is the difference between weather and climate? Weather describes storm systems happening right now, and includes information that can be read from a thermometer this very minute, while climate describes weather patterns over time. Anything involving a set of weather data points is considered climate, including record highs and record lows for temperature and average precipitation. Below are graphs of temperature and precipitation for Tijeras, NM for the year 2013:


 

Each of these graphs for 2013 can be compared to the monthly average from 1914-2005, a range of 91 years:

 

 

 

 The record temperatures for each month between 1914-2005 are recorded in the table below along with the year the record was set:

 
Month
Record
Year
Record
Year
 
High
Recoded
Low
Recorded
January
66°F
1950
-19°F
1949
February
69°F
1986
-20°F
1951
March
75°F
1989
-14°F
1948
April
83°F
1981
5°F
1983
May
92°F
2000
20°F
1967
June
99°F
1981
31°F
1953
July
100°F
1980
38°F
1990
August
95°F
1972
38°F
1968
September
92°F
1958
21°F
1999
October
85°F
1957
6°F
1996
November
74°F
1980
-11°F
1976
December
65°F
1980
-21°F
1990


Another website with helpful climate graphs for the East Mountains is: http://www.usa.com/tijeras-nm-weather.htm

 

 

Thursday, March 13, 2014

Life Zones and the Sandia Mountains


Life zones are geographic areas that are defined by the plant and animal life and living conditions within them.  They are used by scientists to recognize patterns in the natural world, and are determined by a number of factors including elevation, precipitation, and temperature.  What makes understanding the distribution of life zones so difficult is the complex relationship between natural variables across the globe. The Koeppen system is a classification system used to describe Earth’s main climate groups according to latitude, degree of continentality, and location relative to topographic features (Richs, R).
            There is a strong correlation between latitude and elevation regarding plant and animal life.  The correlation between these two factors is positive; for every 1,000 miles in latitude, similar plant life is found 1,000 feet higher in elevation.  This is why similar plant life can be found at higher elevations of the Sandia Mountains as low-elevation places in Canada 4,000 miles north. 
There is also a strong relationship between elevation and temperature.  For every 100 meters in elevation the temperature drops 1°C.  This temperature change is the rate of Adiabatic cooling (Aguado, Edward). When air rises along a mountain side, pressure decreases and the air expands. Because it is doing work the air loses energy and cools, making it generally colder at the top of a mountain than at the bottom. Adiabatic cooling affects the environment of an area and has an influence on life zones found along mountain elevations. 
Mechanism of Adiabatic Cooling
 
A significant correlation between elevation and precipitation also exists.  As the elevation increases, the average precipitation levels also increase.  This is because the most common way to cause condensation in the atmosphere is to cool a parcel of air to its dew point.  Because warm air can hold more water than cold air, as the air is pushed up the mountain range, it cools adiabatically and as it cools it gets closer to the dew point, the temperature at which the moisture in the air saturates.  This causes condensation, cloud formation, and eventually precipitation (Aguado, Edward).
On the other hand, the adiabatic cooling process causes the area on the leeward side of the mountain to have little rainfall because, by the time the wind reaches the other side of the mountain, there is not enough moisture left to precipitate out.  Consequently, mountain sides facing away from the wind receive less moisture.  This area directly down-wind of the mountain is in a rain shadow. 
Illustration of a Rain Shadow
 
A very interesting fact about the Sandia mountain range: it does not follow the rules of a rain shadow. Contrary to what one would expect, because these mountains are exposed to such strong sunlight in the west, even though the prevailing winds come from this direction, the mountain still has very little moisture on the theoretically “wetter” side.  The area that lies in the rain shadow of the Sandia Mountains actually gets anywhere between 0.94 and 3.02 inches of rain per month with a yearly average of 17.39 inches of moisture.
The Rain Shadow of the Sandia Mountains is Affected by Intense Sun Exposure
 
The Sandia Mountains range from 6,200 feet to more than 10,628 feet in elevation. Temperature and precipitation correlate with elevation so closely that most life zones are found along elevation lines and include four main life zones:  the Spruce Fir life zone, the Mixed Coniferous zone, the Ponderosa Pine zone, and the Piñon/Juniper zone.  All four of these are only one life zone in the Koeppen system: a Dfb zone.
The Koeppen system is a classification system that recognizes five major climactic types and minor subgroups in each. The five types are designated by a capital letter and the minor types by lower case letters:

Letter
Description of Classification
A
Tropical Moist Climates: all months have average temperatures above 18 degrees Celsius
B
Dry Climates: with deficient precipitation during most of the year
C
Moist Mid-latitude Climates with Mild Winters
D
Moist Mid-Latitude Climates with Cold Winters
E
Polar Climates: with extremely cold winters and summers

In the case of the East Mountains, the main climate classification is a D—a moist, mid-latitude climate with cold winters—along with an f – signifying it gets precipitation in all seasons—and a b – indicating a land mass that is further into a continent away from any large bodies of water.
 According to the University of Elmhurst, "Dfb and Dwb climates are immediately north of hot summer continental climates, generally in the high 40s and low 50s in latitude in North America and Asia." In this case, because of the elevation of the mountains even though the East Mountains are not in the latitude range they qualify as this type of climate (see above correlation between latitude and climate).
Overall, the Climate of the East Mountains can be classified as a Dfb climate in the Koeppen System even though it does not completely describe the unique mountain environment.
 
 
Sources:
Aguado, Edward, and James E. Burt. Understanding Weather and Climate. Upper Saddle River, NJ: Pearson Prentice Hall, 2007. Print.
Julyan, Robert, and Mary Stuever. Field Guide to the Sandia Mountains. Albuquerque: University of New Mexico, 2005. Print.
Richs, R. "Koeppen Climate Classification." Elmhurst.edu. Elmhurst College, 2005. Web. 13 Mar. 2014. <http://www.elmhurst.edu/~richs/EC/101/KoppenClimateClassification.pdf>.
Day, John A. "Clouds." NWS JetStream - Online School for Weather. National Weather Service, 2008. Web. 13 Mar. 2014. <http://oceanservice.noaa.gov/education/yos/resource/JetStream/synoptic/clouds.htm>.