Discussion 1Years of Living Dangerously Season 2 Episode 2
This documentary television series shows 1) real estate in Miami under the context of climate change and 2) what climate/paleoclimate scientists are actually doing in the field under extreme conditions and in the lab. Numerous well-known scientists share their enthusiasm about their research and explain their cutting-edge research in unique areas ranging from the tropical oceans to deep sea. Watch the video and answer the following two questions. Respond to at least two peer postings. Due by February 11th.
- According to the scientists featured in this documentary, what is the relationship between changing climate and hurricanes? 300 words
- Based on what you learned from this documentary, project a possible near-future scenario on human society. 300 words
The link to the video can be found below
Cite at least 4 sources from credible sources
Arctic Climate Change
The difference during summer
is increasing as the sea ice
extension is decreasing in
relation to the recent past.
In lecture 1, we learned about the seasonal migration of Arctic
sea ice extension. In this figure, it is very clear that 2012 was
exceptional because the Arctic sea ice during that summer was
at the greatest minimum ever observed, dropping far below the
mean of the long term trend. Let’s take a look what happened
after, particularly in 2016.
(National Snow and Ice Data Center)
This figure is based on a report of sea ice extension in November
2016. At the end of summer in 2016, the minimum sea ice
extension was the second lowest after the 2012 extension (left
red arrow). As the season migrates and turns colder, the sea ice
did not grow back as fast as it should have relative to all
previously measured patterns (right red arrow). By November, the
sea ice extension was the lowest ever recorded in November.
What was happening in 2016?
Daily mean temperatures for the Arctic area north of the
80th northern parallel. (Danish Meteorological Institute)
Arctic temperatures are about 20 degrees Celsius higher than normal
above 80 degrees North Latitude! (Nov 2016).
This figure shows daily temperature measurements in the Arctic at 80 degrees north in
2016 (red line) along with a computer simulation of temperature patterns based on long-
term temperature measurements of the Arctic region (green line). The blue line is the
point of freezing (0 degree Celsius). Please note that Y-axis identifies temperature shown
in units Kelvin (K). Kelvin is a commonly used unit of measurement in science for
temperature. Please see the following slide for more detail. The X-axis identifies the
number of days in 2016. For example, the day 1 indicates January 1st, and the day 365
equates to December 31st.
As you can see, there is seasonal variation. You will also notice that, most of the year, the
temperature remains below the freezing level (blue line), although it will slightly exceed
freezing for a short period of time during summer. In November of 2016, the temperature
north of 80 degrees latitude was around -5 degrees C. This is below freezing (not by
much), but is anomalous to the normal temperature of around -25 degrees C (see vertical
blue dashed line). The temperature difference between the long term mean (green line)
and the observed temperature (red line) was as great as 20 degrees!!
Why was this happening? Why did it happen in the Arctic? This phenomenon is
known as polar amplification and it is important that we learn about this
concept to understand how and why changes in our climate system affect
different parts of the world unequally. For now, maintain an awareness of polar
amplification as we will learn more about this concept in the following weeks.
In the meantime, please take a moment to think about whether such daily
temperature changes north of 80 degrees latitude are considered “climate” or
Further, please check the latest news from Arctic Sea Ice News and Analysis for
additional information: https://nsidc.org/arcticseaicenews/
A recent science study reports that
rapid warming in the Arctic is a likely
driver of the recent extreme winter
weather in the US.
Fahrenheit is a temperature scale based on one proposed in 1724 by the
German physicist Daniel Gabriel Fahrenheit. 0 F was the lowest temperature
Dr. Fahrenheit could measure, 100 F is the average human core body
temperature. In scientific measurement, Kelvin is more common because by
definition 0 Kelvin is called absolute zero. Absolute zero is theoretically the
lowest possible temperature where all molecules seize their motion (almost no
heat is emitted by the molecule). In this slide, temperatures in Fahrenheit,
Kelvin, and Celsius are compared in the same scale.
• Weather affects nearly everyone, every day.
• Weather forecasts are issued:
o To save lives
o Reduce property damage
o Reduce crop damage
o To let the general public know what to expect
• Forecasts are often utilized to make many important decisions on
a daily basis
• So how is it done, and how is it done correctly?
National Weather Service Mission:
• The NWS provides weather, hydrologic, and climate
forecasts and warnings for the US, its territories,
adjacent waters, and ocean areas for the protection
of life and property and the enhancement of the
Tools available to a forecaster…
• Weather Observations
(including surface data, satellite data, and radar data)
• Commercial aircraft data
• Wind profilers
• Numerical Model Output
…There are a lot of sources for data!
Forecasting technique – Persistence
13Image from WW2010 Online Guide
The most primitive method of forecasting is to observe and estimate that
there will be no changes to the present. Today is sunny, therefore, tomorrow
will also be sunny. This may work relatively well in a dry and arid region, but
does it work in the New England region? Probably not.
The Trend Technique
15Image from Meteorology Today by C. Donald Ahrens
Another method of forecasting that has been used in the more recent past is to
understand trends. As we all know, however, weather systems migrate from west
to east in the mid latitude, where we live, due to prevailing wind called the
westerly (we will cover this in the following weeks). The atmospheric pressure
system, in general, crosses over North America in 3 to 5 days. With this, the
system travels approximately 800 miles per day. With this understanding, we can
broadly predict when a storm will approach a specified region. Can this be used
to make an accurate prediction? Although this maybe not be a desirable way to
forecast for a long-term period, it may work for a shorter and current time
The Analogue Technique
The analogue technique is a combination of climate and weather. Based on long-
term observations, you might be able to identify a clear pattern in the
atmospheric system. For instance, you may notice that, statistically, when a dry
and cold weather pattern is observed in the northwest (high pressure system),
there is a tendency for stormy weather in the northeast (low pressure system).
This method could be useful and may produce relatively reliable results for
slightly longer time periods (few days to a week).
Accuracy and skill in forecasting
After you learn about forecasting techniques, you may be asking yourself
– what is an ”accurate” forecast?
• What is an accurate forecast?
o Your forecast for tonight’s minimum temp is 0F
If the actual minimum was 1F, is it inaccurate??
If the actual minimum was 10F, is it inaccurate??
o Accuracy (in forecasting) is arbitrary and relative – it is not
clearly or objectively defined.
Modern weather forecasts are based on model
– Numerical Weather Prediction
In order to increase accuracy, we heavily rely on numerical weather prediction.
• Predict the state of the atmosphere (e.g., pressure,
temperature, precip, winds, etc) in time
• Use mathematical equations – initialized with observational
…Why are models often wrong?
Problems with numerical modeling
• Models represent a “simplified” atmosphere – not every real
process in atmosphere can be resolved in models.
• Many are not global in coverage
• The initial atmospheric state is not well-known
• The data may also have errors in it
• The model equations compute quantities at grid points (30-
• The atmosphere is fundamentally chaotic!
So, the atmosphere is fundamentally chaotic and this is why weather
forecasting, although state of the art, is still not perfect. Therefore, in order
to understand the climate system, scientists focus on key phenomena and/or
relationships that effectively control or alter the climate system of the Earth.
Here, we call them the “climate knobs” and let’s talk more about it in the
Here is a news from weather forecast development:
Artificial Intelligence May Be Key to
Better Weather Forecasts
Recent advances in machine learning
hold great potential for converting a
deluge of data into weather forecasts
that are fast, accurate, and detailed.
By Sid-Ahmed Boukabara, Vladimir
Krasnopolsky, Jebb Q. Stewart, Stephen
G. Penny, Ross N. Hoffman, and Eric
Maddy, 1 August 2019
“In 2021, there were 20 weather/climate disaster events with losses exceeding $1 billion each
to affect the United States.” “Overall, these events resulted in the deaths of 688 people and
had significant economic effects on the areas impacted.”
2021 was world’s 6th-warmest year says NOAA
– Could we have predicted that 2021
would become the 6nd warmest year on
record or predict what 2022
temperatures will look like when the
report becomes available? The answer
is no. However, you can look into the
long-term trend and anticipate what
likely will happen in the future!
(weather vs climate)
Please take a moment to read the article published in March 2017 about our
perceptions of climate change. This was before the catastrophes caused by Hurricane
Harvey and Hurricane Irma in 2017.
How Americans Think About
Climate Change, in Six Maps
By NADJA POPOVICH, JOHN SCHWARTZ
and TATIANA SCHLOSSBERG
MARCH 21, 2017
Example Test 1 question:
Climate differs from weather in that
A. climate is a broad composite of temperature
conditions, while weather addresses temperature
as well as precipitation, snow and ice cover, and
B. climate change occurs over longer durations than
do weather changes.
C. climate change is exclusively global, whereas
weather is exclusively regional.
D. climate and weather do not differ, they are
At last, here is an example questions in preparation for the test. The
questions in test 1 will be similar in format to this question, but not
necessarily the same question.
The answer is B.