What is the state of Arctic Ice?

The melting season for Arctic Sea Ice has started with a quick drop in ice. The total ice is at a record low for this time of year (orange line in chart). But, how this plays out throughout the melting seasons is hard to predict based solely on past seasons. For instance, 2012 is the year of the record low (dashed line), but numerous seasons have been lower than 2012 at this time of year (2016 – yellow, 2015 – green, 2007 – blue shown here).  Arctic Sea Ice extent is updated daily on the Charctic Interactive Sea Ice Graph by NSIDC. This graph allows the user to select years, download the image, and choose between Arctic and Antarctic ice extent. NSIDC posts the data and there is a project on both the Calculus and Statistics page using this data, as well as an interactive graph.

How much money do migrants send home to individuals?

Pew has an interactive graph on their Remittance flows worldwide in 2017 page where you can select a country and either outgoing or incoming. The result is get a map of how much money was sent to other countries or came into the country. For example, the graph here is for money sent from the U.S. to other countries. Along with the map, a table of data is updated to match the selection on the map.  A related Pew article, Immigrants sent a record amount of money home to sub-Saharan African countries in 2017 by Abby Budiman and Phillip Connor (4/3/19), highlights this data.

Money sent by immigrants to their home countries in sub-Saharan Africa reached a record $41 billion in 2017. This represents a 10% jump in remittances from the previous year, the largest annual growth for any world region, according to a Pew Research Center analysis of World Bank data.

Worldwide, immigrants sent a record $625 billion (in 2018 U.S. dollars) back to their home countries in 2017, a 7% increase from the previous year.

 

What’s new at sustainabilitymath?

There are three more interactive graphs on the Interactive Graphs page for a total of five.  One is Arctic Sea Ice extent by year for the months of March (high month), June, September (low month), and December, along with regression lines and residual plots (snapshot here). The other two represent the expected years to live at a given age. One of these is by race and gender, while the other is all females and males. Both graphs include a regression line and residual plot. The purpose of these graphs is to not only be interesting and informative, but to also be useful as classroom resource for projects or exercises.

What is Population Bracketology?

The Census Bureau has a new interactive data visualization called Population Bracketology (see the screen shot here). In the game, players have to choose the city (or state for the state version) with the largest population.  Once the game is completed users can scroll over the cities (or states) to get the size of their population.  So, how much do you know about city and state population sizes? Play the game and find out.

How much coal does the U.S. export?

The EIA article In 2018, U.S. coal exports were the highest in five years (3/27/19) summarizes coal exports.

While U.S. coal consumption has generally declined since its 2008 peak, EIA expects that U.S. coal exports reached 116 million short tons (MMst) in 2018, the highest level in five years, based on foreign trade data collected by the U.S. Census Bureau. Exports of coal from the United States have increased since 2016 as international prices have made it more economic for U.S. producers to sell coal overseas.

While coal production in the U.S. has been on the  decline (2014: 1,000,048,758 short tons;  2015: 896,940,563;  2016: 728,364,498;  2017:774,609,357 ) along with consumption, exports have been increasing. This raises philosophical questions.  U.S. coal CO2  emissions have gone down due to burning less coal, but should U.S.  CO2 emissions include U.S. coal burned in other countries?  If a country removes fossil fuels from the ground, how complicit are they in the CO2 emissions of those fuels even if they aren’t the ones burning it?

The EIA article includes links to the data such as the Annual Coal Report page.

How will raising the federal minimum wage impact workers?

The EPI article, Raising the federal minimum wage to $15 by 2024 would life pay for nearly 40 million workers, by David Cooper (2/5/19) covers their analysis of raising the minimum wage.  Their graph here shows the gap between the minimum wage and median wage over time. The report is lengthy and detailed. A few quick highlights:

Raising the minimum wage to $15 by 2024 would undo the erosion of the value of the real minimum wage that began primarily in the 1980s. In fact, by 2021, for the first time in over 50 years, the federal minimum wage would exceed its historical inflation-adjusted high point, set in 1968.

All told, raising the minimum wage to $15 by 2024 would directly or indirectly lift wages for 39.7 million workers, 26.6 percent of the wage-earning workforce.

Indexing the minimum wage to the median wage would ensure that low-wage workers share in broad improvements in U.S. living standards and would prevent future growth in inequality between low- and middle-wage workers.

The article has over 20 graphs/charts/tables and each one has the associated data.  The report does include “a discussion of the research on the likely effects such a raise would have on businesses, employment, and low-wage workers’ welfare.”

How well do you know Antarctica?

Monthly average sea surface temperatures in the Southern Ocean around Antarctica from 1850–2017, based on NOAA’s ERSSTv5 data set. Analysis by Climate Reanalyzer, University of Maine Climate Change Institute.

 

The Climate.gov article Antarctica is colder than the Arctic – but it’s still losing ice by Michon Scott (3/121/19) is a detailed primer on Antarctica and it’s relation to climate change. Some basic facts about Antarctica:

Thanks to thick ice, Antarctic elevation averages more than 6,000 feet (more than a mile above sea level). The very highest parts of the ice sheet, near the center of East Antarctica, rival the height of its tallest mountains, at nearly 13,500 feet.

Antarctica’s interior gets so little precipitation that it counts among the world’s driest deserts. Air masses reaching the high-elevation interior are usually stripped of moisture. The U.S. Antarctic Program reports that, continent-wide, Antarctica receives an average of roughly 2 inches of precipitation per year. (Phoenix, Arizona, gets about 7.5 inches of annual precipitation.)

Is Antarctica warming? It’s complicated:

The Intergovernmental Panel on Climate Change (IPCC) synthesis report published in 2014 found a warming trend over Antarctica, but expressed low confidence that the warming was caused by human activities. In the late twentieth century, the ozone hole and its effects on air circulation may have partly shielded the continent from the global warming influence of greenhouse gas emissions. Continued success in addressing the ozone hole, along with fossil fuel emissions, may cause Antarctic temperatures to rise more rapidly in future decades.

West of the Antarctic Peninsula, measurements dating back to the 1950s show a strong warming trend in the upper ocean: nearly 2.7°F. Meanwhile, waters of the Arctic Circumpolar Current (ACC), far below the surface, have warmed faster than the rest of the global ocean. Between depths of 1,000 and 3,000 feet, ACC temperatures rose by 0.11°F per decade between the 1960s and the 2000s. Between the 1980s and 2013, ACC temperatures at those depths rose by 0.16°F per decade.

What about ice melting?

In contrast with the Arctic—where climate change is amplified, and sea ice shows a clear declining trend over time—Antarctic sea ice does not show a significant overall trend in either the summer or the winter. One region, south and west of the Antarctic Peninsula, has shown a persistent decline, but this trend is small relative to the high variability of the other Antarctic sea ice regions. In 2015, sea ice experts concluded that the small gains in Antarctic sea ice in some seasons were not enough to cancel out Arctic losses, and so globally, sea ice was declining. That basic conclusion remains true in early 2019.

But what if all the ice on the continent melted?

If the entire Antarctic Ice Sheet were to melt at once, it would raise global sea level more than 180 feet. Outside of an epic natural disaster such as an asteroid slamming into Antarctica, that ice sheet isn’t going to melt entirely for centuries, but it will contribute to sea level rise over the next century. The question is: How much? The exact answer is elusive. The IPCC Fifth Assessment Report (AR5) states that the effect of Antarctic ice sheets on sea level rise over the coming century is a major unknown. Not only is the ice sheet melt rate challenging to measure precisely, but other events could accelerate sea level rise, and it’s hard to know when or even if those events will occur.

Read the article and get to know Antarctica. The is ample stats and QL classroom opportunities and graphs in the article.

 

What are the gender trends in graduate school?

The Council of Graduate Schools (CGS) report, Graduate Enrollment and Degrees 2007 to 2017 (Oct 2018) provides data on enrollment and degrees in graduate school by gender and race.  For example, the graph here is Figure 2 in their report and provides enrollment data by field of study and  gender.  In the aggregate they note:

Academic year 2016-17 marked the eighth consecutive year in which women earned the majority of degrees awarded at the doctoral level. Women earned 64.0% of graduate certificates awarded in 2016-17, 57.3% of master’s degrees, and 53.0% of doctorates.

The report contains a number of graphs and data tables with various  demographic information (race, gender, international). For example,

Among first-time U.S. citizens and permanent resident graduate students in the Fall of 2017, about 23.9% were underrepresented minorities, including American Indian/Alaska Native (0.5%), Black/African American (11.9%), Native Hawaiian/Other Pacific Islander (0.2%), and Hispanic/Latino (11.3%) (Table B.11).

A summary page of the report, First-Time Enrollment Holds Steady – Application Counts Slightly Decline at U.S. Graduate Schools, also has a link to the full pdf report.

How many ways does NASA use pi?

At least 18 according to the Jet Propulsion Laboratory at NASA based on the article for pi day — Oh, the Places We Go: 18 Ways NASA Uses Pi.  Number 12 on the list: Keeping rover wheels turning:

Rover wheels have distinct designs on them that leave patterns on the ground as they turn. These patterns serve as visual markers that help operators while driving the Mars rovers remotely from Earth. Pi is used to calculate how far the rover should travel with each wheel rotation. By measuring the distance from one wheel mark to another, rover drivers can determine if the wheels are slipping or if they’ve driven the expected distance.

Each of the 18 on the list has an associated project with a printable poster. The  Celebrate Pi Day with NASA page has resources for educators, students, and pi day enthusiasts.

0 to 6 or 1 to 7, Does it matter?

The Decoded/Pew Research Center article On a scale from 1 to 10, how much to the numbers really matter? by Jonathan Evans reports on their experiment using a 0 to 6 scale and 1 to 7 scale.

 To carry it out, we randomly assigned respondents in France, Germany and the United Kingdom our political ideology question with one of two 7-point scales: either 0–6 or 1–7. The full question wording using our traditional 0–6 scale was this: “Some people talk about politics in terms of left, center and right. On a left-right scale from 0 to 6, with 0 indicating extreme left and 6 indicating extreme right, where would you place yourself?”

Their graph copied here shows the results of this study. An explanation:

These outcomes suggest that when a scale is easily divided in half — for example, when the maximum value is 6 rather than 7 — it’s more likely for respondents to select the midpoint. Previous research has found that respondents are likely to assume that half the top endpoint is a scale’s midpoint, so when half the top endpoint is not an answer option (e.g., 3.5 on the 1–7 scale), respondents seeking the central point on the scale may sometime choose 3 (not the scale midpoint) and sometimes choose 4 (the actual scale midpoint). Those who received the 0–6 scale could more easily find the midpoint (3) by halving the top endpoint.

The article has other charts and links to methodology.