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North Atlantic also known as the "NAO" which you may of heard now and then. The telliconnection shows us what the pattern is like in the North Atlantic. Whether there's Blocking or not. It has affects on weather patterns for sure in the U.S and I assume elsewhere.
When there's blocking (negative NAO) the Jet Stream can dig down into Eastern U.S sending and keeping cold air around longer since its "blocked" from leaving. When there's blocking, the flow isn't progressive
I haven't read his Thesis yet but I can't wait to do so!
"As noted in section 1.1, anomalous weather conditions associated with atmospheric blocking were recognized since the early 20th century. Recently, several studies investigated the
link between extreme weather and blocking more thoroughly (Green, 1977; Trigo et al., 2004;
Stillmann et al., 2011). Such studies showed that large scale subsidence associated with blocking
highs can lead to prolonged heat waves and drought. Flow anomalies created by blocking events
also create extreme conditions downstream as well. For example, winter time Arctic outbreaks in
the mid-latitudes are often the result of persistent anti-cyclonic flow bringing cold air in from
higher latitudes. "
"Despite several decades of research on atmospheric blocking, the scientific community
has never come to a full consensus as to the dynamics and driving forces behind the
phenomenon. Rossby (1950) and Rex (1950a) provided the first attempt at a physical
explanation, comparing the jet stream to a hydraulic jump whereby the jet stream acts as a
conduit that breaks down a high kinetic energy jet upstream to a low kinetic energy jet
downstream"
Page 12
"Hoskins and Sardenshmukh (1987) and Ferranti 13 et al. (1994) showed that blocking frequency in the North Atlantic varied with SST anomalies over Indonesia and the Caribbean Sea."
Page 15
" Colucci and Alberta (1996) studied 7 consecutive winters to draw conclusions on the relationship
between cyclogenesis and the onset of blocking. They found that cyclogenesis only has a distinct
impact on the onset of blocking events when planetary waves could “precondition” the
background flow through a strong positive meridional flow"
"Lastly, recent studies have investigated the link between atmospheric blocking and
teleconnections, specifically the North Atlantic Oscillation (NAO). Benedict (2004) and Franzke
et al. (2004) showed a connection between the NAO and RWB and the distinct roles that
cyclonic and anti-cyclonic wave breaking have on the weather pattern. "
That's all I got up to for now. That Page 12 finding was interesting to see.. To be continued...
Page 16
"The remainder of this paper will seek to investigate the precursor signals that arise from
the RWB dynamics associated with NA blocking events. Chapter 2 discusses the data,
experiment setup and composite technique used to identify 30 blocking cases in this study. Chapter 3 presents a discussion of the dynamics of the composited NA blocking events as well as
the identification of precursor signals generated by the RWB interpretation of atmospheric
blocking. Chapter 3 also presents a more robust view on the rossby wave train anomalies used to
17 identify precursor signals for the 30 NA blocking events. Finally, chapter 4 will summarize the
findings from this study and present possible pathways for future work. "
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