Snow Algae on Albedo in the Artic
This past June, an article came out on the effects on snow algae on glaciers in the arctic where "researchers found that the presence of the algae, reduced the albedo or reflectivity of the snow by as much as 13 percent" (Popular Science). This algae's inclusion in arctic ecosystem models, like algae in lotic aquatic ecosystems, is essential where it's found to be present, especially since there's been knowledge of its presence since the time of Aristotle! "Recent snow-albedo models for Greenland suggest that melting accelerates largely due to increased contributions from light-absorbing impurities, with impurities being primarily considered to be anthropogenic, forest fire-derived black carbon, Saharan or pro-glacial mineral dust. However, the contribution of coloured algae to changing albedo and melt rates has not previously been considered"(Lutz et al, 2016). In the article, they give evidence of a clear need for snow algae to be given a part in arctic climate models.
The snow algae blooms at the onset of melting and is "independent of location-specific geochemical and mineralogical factors"(Lutz et al, 2016). Most of the bacteria found in the 40 study sites were of the phyla Bacteriodetes, Proteobacteria and Cyanobacteria and their presence varied highly between sites while the snow algae's abundance was consistent with very little diversity (Chlamydomonadaceae was the most abundant species). The snow algae's coloring is due to "a high content of secondary carotenoids (∼70–90%), which are synthesized by the snow algae as a protection mechanism from high levels of irradiation" (Lutz et al, 2016). The homogeneous algal community are the dominate source of primary production on snow and ice fields and locally, they can even reduce the albedo by up to 20% through darkening of glacial surfaces. The negative correlation found between algal biomass and surface albedo is indicative of its addition to the already present positive feedback loop in the arctic through its reduction of surface albedo. This, in turn, furthers yearly glacial retreat.
Article on Popular Science:
Full Scientific Article published in Nature Communications (Lutz et al, 2016):
Thanks for reading,
Date Posted: Dec. 15, 2016, 10:40 p.m.
Weird Winter Weather and Arctic Warming
While the midwest has been subject to freezing temperatures this winter and New England has been experiencing consistently cold temperatures and seemingly endless snow storms, the Western United States is in the middle of a severe drought accompanied by anomalously warm temperatures. Are strange winter weather patterns such as these likely to become more regular?
According to a recent study, they may be. The Arctic is warming twice as fast as any other region of the Earth which is decreasing the temperature difference between the poles and the equator. In turn, a smaller temperature difference causes west-east winds to weaken and for the jet stream to wander further North and South than normal. And a wandering jet stream is in part responsible for the warm dry air over the West and the cold, Arctic air over the Eastern US this winter.
So although the connection is hard to prove definitively, a warmer Arctic may mean a wavier jet stream and more strange weather patterns during winter.
Below you can see the typical jet stream configuration (right) side-by-side with the wavier configuration.
Source: A Melting Arctic and Weird Weather: the plot thickens
Date Posted: Feb. 23, 2015, 5:55 p.m.
CoCoRAHS-Albedo travels to San Jose
Earlier this week I presented a poster of the CoCoRAHS-Albedo network at the inaugural Citizen Science Association conference held in San Jose, California. Scientist, citizens, community organizers and teachers alike were present from over two dozen different countries, including New Zealand, Australia and China!
What was perhaps most interesting was that much time was spent planning how to connect the global community of citizen scientist networks so that ideas may be shared and people may take advantage of what is already in place. As citizen science is a relatively young field, things are constantly evolving; best-practices are changing, recruitment methods are expanding, collaboration between communities, individuals and schools is growing and importantly, the authority of citizen science data in the scientific world is continuously gaining ground.
One other interesting thing I found was that with the exception of the national CoCoRaHS network and the CoCoRAHS-Albedo network, the vast majority of citizen science networks are focussed on observing living creatures. Networks of volunteers who count frogs, salamanders, fish, deer, plants, birds...and so on are everywhere, while the networks of people observing the physical world, such as rain, snow, temperature, steams, etc are much rarer. Perhaps because of this, there was much interest in the CoCoRAHS-Albedo network and its connection to NH climate.
Date Posted: Feb. 13, 2015, 12:47 p.m.
2014: Warmest year on record- What does this mean??
Recently, major science news outlets announced that 2014 was the warmest year on record. But what exactly does this mean?
Since 1880, an array of climate observation stations located around the world have recorded temperatures and other climate variables which provide us with a general understanding of global conditions through time. These stations were joined in the 1960's by satellite observations and together, record temperatures of the oceans and land surfaces worldwide.
To compare individual years, annual ocean and land surface temperatures are averaged and reported relative to the 20th century average. Out of the top 10 warmest years on record, 9 of them have occurred since the year 2000, with the year 2014 being the warmest relative to the 20th century average.
Of the record warmth observed in the year 2014, most can be attributed to heating of the oceans. On average, recorded temperatures in 2014 were 1.24 degrees F warmer than the 20th century average with ocean surface temperatures accounting for 1.03 degrees of the warming!
Another interesting observation is that temperatures in the high Northern latitudes are rising faster than at lower latitudes. Specifically, the Arctic is warming at more than TWICE the rate of other parts of the globe, with the snow/ice-albedo feedback of course playing a large role in the shrinking of sea ice and temperature increase.
Below is a table of the top ten warmest years on record.
NOAA National Climatic Data Center, State of the Climate: Global Analysis for Annual 2014, published online December 2014, retrieved on February 8, 2015 from http://www.ncdc.noaa.gov/sotc/global/.
Date Posted: Feb. 8, 2015, 10:08 a.m.