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Out Of This World

Out Of This World has made the short-list for the 2018 People's Choice Award for Fave Canadian Science Site!

Sponsored by Science Borealis and the Science Writers and Communicators of Canada, the award recognizes Canada's best online science sites and science blogs, and gives the public a chance to choose their favourite from among them.

Watch @SWC_Can and @ScienceBorealis on Twitter during Science Literacy Week (Sept. 17-23) and until the close of voting on September 30th, along with the hashtags #CdnSciFav and #scilit18, as they feature one site and one blog every day, and click the above image to vote for this page as your favourite science site in Canada!



Seasonal Skywatching

With Summer here, warmer nights mean more incentive to stay out late, to take in some of the amazing sights in our night sky. Here are the top astronomical events to look for in the season.

Must see Perseid Meteor Shower headlines Summer skywatching

This Year in Space

There are some awesome events happening in astronomy and space exploration in 2018. Here's a list of the best things going on in space this year.

Super Blue Blood Moon and Falcon Heavy launch kick off amazing year in space!

Space Weather

The Sun not only provides light and heat to Earth and its weather systems, but the activity of the Sun - solar flares, coronal mass ejections, etc - also has other effects, both in the space around Earth and in the upper atmosphere.

These effects are known as space weather.

NASA's Solar Dynamics Observatory (SDO) and NASA/ESA's Solar and Heliospheric Observatory (SOHO) both watch 24 hours a day, 365 days a year, to track activity on and around the Sun. This provides us with ample warning should solar activity potentially threaten our satellites, spacecraft and astronauts in orbit, or our power grids on the ground.

Above are three different views that SDO regularly delivers - track dark sunspots with the HMI Intensitygram (left), see magnetic 'coronal loops' and solar flares with the 171 Angstrom filter (centre), and watch for coronal holes (dark clear patches in the Sun's "atmosphere") with the 193 Angstrom filter (right).

Solar flares can blast immense clouds of charged particles (known as Coronal Mass Ejections) into space, long structures known as Dark Filaments can peel away from the Sun's surface, and Coronal Holes emit fast-moving streams of solar particles (appropriately named Coronal Hole High Speed Streams), all of which can have an impact on Earth's space weather.

When these events are occurring, we turn to SOHO's coronagraph views of the space around the Sun, which are shown below:

SOHO's latest LASCO C2 closeup view of the solar corona (left) and the latest LASCO C3 wide-field view of the corona (right). The blank area in the centre of each image is due to a small disk, positioned at the end of an arm (the dark diagonal line in the LASCO C3 image), to block the Sun's direct rays so that the instrument can record the activity going on around the Sun. The white circle inside the blank disk is the position of the Sun.

The wispy white straight-line streamers emerging from behind the corongraph disk are the streams of solar particles from coronal holes. Coronal mass ejections and dark filament eruptions both show up as arcs of bright material expanding away from the Sun. The points in the background are distant stars, and occasionally, one or more bright planets - Mercury, Venus, Mars, Jupiter or Saturn - will make guest appearances, appearing as a bright diamond that slowly crosses the field of view.

When an expanding cloud of solar particles from a coronal mass ejection or filament eruption sweeps past Earth, or when Earth is plunging into the high speed stream of particles from a coronal hole, the magnetic fields produced by all those moving charged solar particles cause a reaction from Earth's geomagnetic field. The most common effect is that many of these solar particles become caught up in the loops of Earth's magnetic field, and they stream down into the upper atmosphere to produce auroras!

NOAA's Space Weather Prediction Center provides information on these effects!

See the geomagnetic activity around Earth with NOAA's Estimated Planetary K-index (left), which is a measure of the strength of geomagnetic activity (Kp=5 or higher is a geomagnetic storm!), plus check out how far south the auroras may be visible in the next 30 minutes with the Aurora Forecast for the northern hemisphere (right). The brighter the colour of the ring, the higher probability of seeing the aurora. Note that the Kp value is an average of the previous three hours of activity, thus it is better used after the fact, rather than to know when you should go out to try and observe the auroras.

Note: All of the above images update automatically, on a regular basis. Simply refresh the page to load the latest image, or click on an image to see more info or to load a larger view (opens in a new tab).

The Aurora from Space

This composite view of the Aurora from space was captured on the night of September 10-11, 2018, by NASA's polar-orbiting Suomi NPP satellite. The auroral arc is visible across each 'slice' of the composite, with noticeable discontinuities between the different passes, which reveal how the clouds and aurora moved during each of the satellite's roughly 100-minute orbits around the Earth. The numerous tropical cyclones currently in the Atlantic and eastern Pacific Oceans are also noted. (Image credit: NASA Worldview/Scott Sutherland)

Global Carbon Dioxide

The Keeling Curve, provided by the Scripps Institution of Oceanography, gives the daily reading of atmospheric carbon dioxide, in parts per million (ppm), measured at the top of Mauna Loa, Hawaii.

The plots above are presented for comparing where CO2 levels are now, compared to just one year ago (top), to show just how much concentrations have risen since the 1960s (bottom left), and how current levels compare with natural cycles, going back some 800,000 years (bottom right). Air trapped in ice cores reveals that carbon dioxide levels fluctuated over millennia, between around 170 parts per million to just shy of 300 ppm, and with a long-term average at around 220 ppm.

In 2018, the global carbon dioxide concentration peaked at over 411 parts per million, and it will now be decades to centuries before we ever see the yearly minimum dip below 400 ppm again.

Why is this important?

Carbon dioxide is considered to be the 'global climate thermostat' for planet Earth.

What that means is, the abundance of this one greenhouse gas is the primary controller of Earth's surface temperature, and thus its climate. The simple reason behind this is: carbon dioxide is the most abundant temperature-independent greenhouse gas in the atmosphere.

While methane (CH4) is a more potent greenhouse gas - molecule for molecule - than carbon dioxide, there is far less of it in the atmosphere, currently. So, carbon dioxide's contribution to the greenhouse effect far outweighs methane's at this time.

Water vapour is also a more potent greenhouse gas than carbon dioxide, and it is more abundant in the atmosphere, but it cannot be considered to be in control of Earth's climate because of its strong dependence on temperature. If you lower the temperature even a few degrees, water vapour will condense into liquid, and if you cool it further, it will freeze solid, thus removing its contribution to the greenhouse effect. Carbon dioxide, on the other hand, remains in gaseous form - and thus keeps its properties as a greenhouse gas - down to -78.5°C.

Thus, throughout the various ice ages the Earth has gone through, it has been largely carbon dioxide that has regulated the planet's overall temperature.

In the roughly 10,000 years before the mid-1800s, when carbon dioxide levels were fairly uniform at around 260-270 ppm, Earth's climate was fairly stable. The greenhouse gases in the air absorbed just enough of the heat Earth radiated out into space, to keep the planet's average temperature fairly steady, at around 15°C. As shown in the graph below, which was compiled by NASA's Goddard Institute for Space Sciences, from 1880 to 2017, the global average temperature has risen by roughly 1.2°C since pre-industrial times.

Seeing this kind of temperature increase in a small region, over a short period of time, such as in the local forecast for your city over a few days, is not much of a concern. It represents only a small amount of energy, and the temperature will eventually go down by that much, as well. The entire planet warming up by over one degree, however, and in such a way that the temperature will not go down again by that amount for the foreseeable future, is of great concern.

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