How does space weather affect Earth?

In order to protect people and systems that might be at risk from space weather effects, we need to understand the causes of space weather.

The sun is the main source of space weather. Sudden bursts of plasma and magnetic field structures from the sun’s atmosphere called coronal mass ejections (CME) together with sudden bursts of radiation, or solar flares, all cause space weather effects here on Earth.

Space weather can produce electromagnetic fields that induce extreme currents in wires, disrupting power lines, and even causing wide-spread blackouts. Severe space weather also produces solar energetic particles, which can damage satellites used for commercial communications, global positioning, intelligence gathering, and weather forecasting.

The main area of concern will most likely be our nation’s electric power grid. Northern territories are more vulnerable to these effects than areas farther south.  Generally, power outages due to space weather are very rare events, but evidence suggests that significant effects could occur.  These power outages may have cascading effects, causing:

  • Loss of water and wastewater distribution systems
  • Loss of perishable foods and medications
  • Loss of heating/air conditioning and electrical lighting systems
  • Loss of computer systems, telephone systems, and communications systems (including disruptions in airline flights, satellite networks and GPS services)
  • Loss of public transportation systems
  • Loss of fuel distribution systems and fuel pipelines
  • Loss of all electrical systems that do not have back-up power

The NOAA Space Weather Scales report three categories of solar effects. These scales communicate current and future space weather conditions, and their possible effects on people and systems. Similar to the Saffir-Simpson Hurricane Wind Scale, the NOAA space weather scales correlate space weather events with their likely effects on technological systems. As shown in the table below, the scales describe the environmental disturbances for three event types: Geomagnetic Storms (G-scale), Solar Radiation Storms (S-scale), and Radio Blackouts (R-scale). The scales have numbered levels, analogous to hurricanes, tornadoes, and earthquakes that convey severity.

The vast majority of “5” level events will not cause catastrophic damages to the electric grid.  On average, the Earth is impacted by such storms about four times during every 11-year solar cycle, so many large storms have impacted the planet since the Carrington Storm with much less signification impact.

Watches are used for making long-lead predictions of geomagnetic activity.

Warnings are used to raise the public’s level of alertness based on an expectation that a space weather event is imminent.

Alerts indicate that the observed conditions, highlighted by the warnings, have crossed a preset threshold or that a space weather event has already started.

If space weather alerts have been issued, here are things that you must do during the event:

  • Follow energy conservation measures to keep the use of electricity as low as possible, which can help power companies avoid imposing rolling blackouts during periods when the power grid is compromised.
  • Follow the Emergency Alert System (EAS) instructions carefully.
  • Disconnect electrical appliances if instructed to do so by local officials.
  • Do not use the telephone unless absolutely necessary, during emergency situations keeping lines open for emergency personnel can improve response.

Taking care after the event:

Throw out unsafe food:

  • Throw away any food that has been exposed to a temperature of 40° F (4° C) or higher for 2 hours or more or that has an unusual odor, color, or texture. When in doubt, throw it out!
  • Never taste food or rely on appearance or odor to determine its safety. Some foods may look and smell fine, but if they have been at room temperature too long, bacteria causing food-borne illnesses can start growing quickly. Some types of bacteria produce toxins that cannot be destroyed by cooking.
  • If food in the freezer is colder than 40° F and has ice crystals on it, you can refreeze it.
  • If you are not sure food is cold enough, take its temperature with a food thermometer.

While the last big geomagnetic storm was in 1989, solar flares can cause small disturbances in electronics and power grids. While no alerts are active currently, it is better to be prepared and bring awareness to the impact that space weather can have on Earth.

 

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