Valdez, AK 100 Million Years in Past and Future

Humans have existed for an insignificant amount of time on the planet, and during our time here the continents have remained observably stationary; however, throughout geologic time our continents and the distribution of land masses has actually varied quite greatly. In response to these shifts in land mass, our planet undergoes a number of consequences, probably the most severe of which is climate change. As we have learned throughout class this semester, the position and arrangement of land masses greatly affects the patterns that air masses, ocean currents, and our overall climate undergo. This specific blog will focus on how these shifts change the climate of Valdez, Alaska both 100 million years in the past and future.

Valdez in the Present:

Present climograph of Valdez

Valdez's present location

Valdez in the Past:

Valdez's location 100 million years in the past







Climograph of the Past




The climate of Valdez 100 million years ago must have varied greatly from where it sits today. First, the physical location of Valdez is currently 61 degrees north and 146 degrees west, but long ago Valdez was a few degrees north and east at the location 63 degrees north and 142 degrees west. The effect that the variation of physical location on the climate of Valdez is probably minimal, but there are a variety of other factors that could change the climate. Currently the Aleutian Low sits off in the Bering Sea and interacts with the polar highs coming off of the cold, large part of the continent to form enormous storms that dump record snowfall on Valdez. Well, a 100 million years ago the entire northern part of Canada and the Yukon were separated by water, lessening the continentality of the area, lowering the high pressure, and most likely preventing the Chugach mountain range from forming yet. The climatic effects on the Valdez area would be vast. The area would still see a low pressure system that sits off the coast, but the storms pushed in by the westerlies would not be as often or severe because the high pressure coming off the continent would be minimized--lessening the pressure gradient--and the Chugach mountain range would be non-existent, eliminating the orographic effects that cause record snowfall. Furthermore, Valdez would still be considered a maritime climate and would be much less effected by the continental polar and arctic air masses than by the maritime polar air masses, slightly warming temperatures in the area during the winter months. Overall, Valdez would still see dramatic storms as a result of the Aleutian Low and the polar high created by the land masses further east, but the severity of the storms, the amount of snowfall, and the wind velocities would diminish, but the temperatures would rise slightly 100 million years ago.

Valdez in the Future:

100 million years in the future




Climograph of the Future

The climate of Valdez 100 million years in the future would be much different than it was 100 million years in the past. The Aleutian Low would still be the main contributor to Valdez weather, creating storms when it interacts with high pressure to the east, but the storms would be more often and severe than 100 million years in the past because the land mass to the east would be much larger, bringing larger forces of continentality and high pressure. The physical location of Valdez would be much further southwest, probably sitting somewhere around 58 degrees north and 150 degrees west, causing minimal climate variation except for a slight warming in seasonal temperatures as shown by the climograph. The Chugach mountain range would still be a factor, having possibly even grown in size due to the collision of tectonic plates, forcing air masses upward orographically resulting in massive snowfall. One of the largest differences in the future compared to the present is the massive gulf created between Quebec and the Yukon. This gulf would attract low pressure, probably forming something like the Aleutian Low but to the East of Valdez. This semi-permanent system would put Valdez in the middle of two low pressures, which would most likely mean more frequent, violent, and precipitous storms for Valdez as a result. Valdez would still be considered a maritime climate because maritime polar air masses would be affecting the location most of the time, but continental polar and arctic air masses would influence the area more so than 100 million years in the past. Overall, Valdez would see more frequent snowfall and precipitation as a result of its unique position between two low pressure systems and the possible growth of the Chugach mountain range, but the location would remain maritime and temperatures would warm only slightly because of its shift to the south and the resulting increase of incoming solar radiation.

Limon, Costa Rica versus Valdez, AK

Costa Rica and Valdez are climatically different in many ways. The most obvious difference can be found in their latitudinal variations, with Costa Rica sitting at 10 degrees North and Valdez at about 57 degrees North. On the Koppen-Geiger scale Costa Rica is labeled as equatorial, while Valdez is labeled as snowy. The climographs show that Costa Rica has a much less variable temperature range than does Valdez, with Costa Rica's temperatures staying between 75 and 80 degrees the entire year. Both areas sea precipitation in high amounts, but Valdez sees vast amounts of snow as a result of its high latitude, proximity to the Chugach mountain range, the Aleutian Low, and polar air masses, while Costa Rica sees much more precipitation than Valdez in the form of rain due to the maritime tropical air masses. As is obvious by the climographs, Costa Rica sees a significant amount more precipitation than Valdez, especially in July, where Valdez sees one of its driest months and Costa Rica sees its wettest month. The equatorial climate of Costa Rica is subject to maritime tropical air masses that are rich with moisture and humidity, exposing Costa Rica to severe hurricane risk, whereas Valdez does not see hurricanes, just large mid-lattitude cyclones. Both areas are affected by some sort of low pressure system, as Valdez sits next to the Aleutian Low and Costa Rica is affected by the ITCZ--a low pressure system created by the meeting of trade winds that moves north in the summer to affect Costa Rica. The ITCZ, and the Aleutian Low, can drop tremendous amounts of precipitation in both Valdez and Costa Rica.

Sources: http://climate.gi.alaska.edu/climate/Climographs/VDZ.html

http://www.world-climates.com/city-climate-limon-costa-rica-north-america/

Both areas are affected by some sort of low pressure system, as Valdez sits next to the Aleutian Low and Costa Rica is affected by the ITCZ--a low pressure system created by the meeting of trade winds that moves north in the summer to affect Costa Rica. The ITCZ, and the Aleutian Low, can drop tremendous amounts of precipitation in both Valdez and Costa Rica.

Source: http://en.wikipedia.org/wiki/File:ITCZ_january-july.png

The Meso and Micro Scale Climate of Valdez, AK

Of the four mesoscale influences listed in the class lecture, Valdez Alaska experiences all of them: orographic, water, atmospheric circulation, and air mass influences. As mentioned in previous blog posts, Valdez is nestled between the Chugach mountain range and the William Sound of the Pacific Ocean. The Chugach mountain range has significant orographic influences on the city of Valdez, forcing air masses from sea level to over six thousand feet--giving birth to monumental snowfall from moist air masses blowing in from the Aleutian Low and Bering Sea. The William Sound and the Pacific Ocean also influence the mesoscale climate of Valdez. Because water heats up and cools down faster than land, Valdez experiences a more moderate temperature range than other towns in Alaska as more energy goes into the latent heat flux and not the sensible heat flux. The Aleutian Low that sits to the west of Valdez in the Bering Sea also has a tremendous effect on Valdez's climate. Especially during the winter months, the high pressure that is initiated by the cold, heavy air of inner Alaska and the northern arctic creates a pressure gradient with the Aleutian Low to form enormous storms. Finally, the air masses that affect the mesoclimate of Valdez include the maritime polar, continental arctic and continental polar air masses. In the winter months, the continental arctic and polar air masses influence the area more, whereas the maritime polar air masses influence Valdez more in the summertime.

Source: http://minnesota.publicradio.org/collections/special/columns/updraft/archive/2010/02/forecast_last_arctic_blast_of.shtml

In addition to mesoscale climatic effects, there are also numerous microscale influences on Valdez. Valdez sits at the base of a river valley that extends up into the Chugach. This has several effects on the microclimate, including windy conditions and cold air ponding. Cold air hugs the lowest elevations, and the river valley funnels the cold air from the mountains down into Valdez, but it also funnels wind from the high pressure gradient forces that Alaska is known for. As for anthropogenic effects on Valdez's climate, there are few because people are sparse and the environment as a whole is effected very little by the activities of Valdez. To my knowledge, there are no invasive species issues, smog, irrigation, or other anthropogenic influences in the are.

Aerial view of Valdez, AK sitting between the Chugach and William Sound

http://www.alaska-in-pictures.com/port-of-valdez-aerial-3068-pictures.htm

The Koppen Geiger scale classifies Valdez as a DFC, where they experience a snowy climate, very humid conditions, and a cool summer, which accurately depicts the climate of Valdez according to my observations.

Aerial photo of Valdez Airport where the weather station I am using is located

http://www.airphotona.com/image.asp?imageid=12109

It is difficult to get annual precipitation data from the weather stations in and around Valdez; only one of the four stations had precipitation data. Of the data that I could find, the year of 2011 has been very dry in Valdez with only 21 inches of precipitation, whereas 08', 09', 10' saw 37 inches, 42 inches, and 33 inches respectively. There is still one month left in the year for Valdez to make up some ground, but historically they don't see much precipitation in December. In reference to temperature, I did have access to temperature data dating back to the 70's; however, there was no consistent pattern of temperature swings that I could determine from the monthly data that was available.

Source: http://www.wunderground.com/weatherstation/WXDailyHistory.asp?ID=MRHVA2&graphspan=year&month=12&day=1&year=2011