Climate change is at the forefront of environmental concerns and it often revolves around atmospheric carbon dioxide concentration and its effect on average surface temperature. However, carbon dioxide concentration is not only rising in the atmosphere but in the ocean as well. The source of this dissolved carbon dioxide is the rising atmospheric carbon dioxide levels we hear so much about, as carbon dioxide is soluble in water.
First, what is particulate matter (PM)? Particulate matter is a mixture of solids and/or liquids suspended within the air. These solids and liquids are too small for the eye to see, however, if they're in a high enough concentration it will often look like a haze in the air. The particles that make it up can be anything from pollen and dust to even molecules of water. The number at the end (ex. the 10 in PM10) is the upper limit of the particles’ diameter. A size comparison produced by the US EPA can be seen below.
It is almost instinctive when you first get the PocketLab Air to breathe directly on it just to see what happens. As seen below, of the PocketLab Air's seven sensors, five of them detect changes from a direct human breath. These parameters are carbon dioxide, particulate matter, temperature, humidity, and pressure. The most interesting of these is the sharp rise in carbon dioxide which, as the most important greenhouse gas, brings about strong connections to the topic of climate change.
Background Information about Ozone
Ozone (O3) in our atmosphere is both good and bad. There is a helpful saying to remember is, “Ozone: good up high, bad nearby.” The “good” ozone is ozone high in our atmosphere that is part of the ozone layer. The ozone layer protects us from the sun’s ultraviolet rays. “Bad” ozone is ozone that occurs at ground level, where it can be inhaled. Ground level ozone is a pollutant and creates smog.
Background Information on Particulate Matter
Particulate matter consists of small particles suspended in the atmosphere. Dust, pollen, sea salt, soil particles, mold, soot, smoke, and other fine substances create a mixture of particulate matter that we inhale with every breath. According to the EPA, particulate matter greater than 10 micrometers is generally filtered away in our nose and throat. Particulates less than 10 micrometers can often pass into the lungs.
Carbon dioxide circulates naturally in Earth’s atmosphere as part of the carbon cycle (the process in which carbon dioxide is exchanged between the atmosphere, oceans, soil, plants, and animals). According to the EPA, since the industrial revolution, humans have altered the carbon cycle through activities like burning fossil fuels, which adds CO2 to the cycle, and deforestation which reduces natural ways in which CO2 is removed.
A PocketLab Voyager Hand Dynamometer
Hand and finger strength is vital in many aspects of life--from sports such as rock climbing to jobs including airline baggage workers. PocketLab Voyager's tactile sensor can be used to construct a very simple hand dynamometer to measure strength of a person's hands and fingers. Figure 1 shows a simple dynamometer constructed by the author. It consists of a 2" x 2" x 4" block of wood to which the PocketLab tactile sensor has been attached using removable double stick poster tape.