GOES-R Goes Up!

Artist impression of the GOES-R satellite. Image courtesy of NASA.

Artist impression of the GOES-R satellite. Image courtesy of NASA.

On Saturday, 19th November, at 10.42pm GMT the Geostationary Operational Environmental Satellite-R Series (GOES-R) is due to be launched from Cape Canaveral in Florida, USA.

The GOES-R is a geostationary weather satellite operated by the National Oceanic & Atmospheric Administration (NOAA) Department of the US Government. It will the latest in the NOAA’s GOES series of satellites, and will take the moniker GOES-16 once it is in orbit, joining the operational GOES satellite constellation comprising of GOES-13, GOES-14 & GOES-15.

It will be put into a geostationary orbit at around 35 800 km above the Earth which will allow it to match the Earth’s rotation, meaning that it will effectively stay over a specific point on the Earth. It will be located approximately at 137 degrees West longitude, and through the constellation will provide coverage for North, Central and South America together with the majority of the Atlantic and Pacific Oceans.

Artists impression GOES-R satellite and its instruments. Image courtesy of NASA.

Artists impression GOES-R satellite and its instruments. Image courtesy of NASA.

The instrument suite aboard the satellite has three types: Earth facing instruments, sun facing instruments and space environment instruments.

Earth Facing Instruments: these are the ones we’re most excited about!

  • Advanced Baseline Imager (ABI) is the main instrument and is a passive imaging radiometer with 16 different spectral bands: two visible bands – Blue and Red with a spatial resolution of 0.5km, four near-infrared with spatial resolutions of 1 km; and ten infrared bands with a spatial resolution of 2 km. As its in a geostationary orbit its temporal resolution is extremely high with the full mode being where the Western Hemisphere is imaged every 5 – 15 minutes, whereas in its Mesocale mode (providing a 1000 km x 1000 km swath) the temporal resolution is only 30 seconds.
  • Geostationary Lightning Mapper (GLM) is, as the name suggests, an instrument that will measure total lightning, and both in-cloud and cloud-to-ground lightning across the Americas. It is an optical imager with a single spectral band of 777.4 nm which can detect the momentary changes in the optical scene caused by lightning. The instrument has a spatial resolution of approximately 10 km.

Sun Facing Instruments

  • Extreme Ultraviolet and X-ray Irradiance Sensors (EXIS) instrument has two sensors to monitor solar irradiance in the upper atmosphere; these are the Extreme Ultraviolet Sensor (EUVS) and the X-Ray Sensor (XRS).
  • Solar Ultraviolet Imager is a telescope monitoring the sun in the extreme ultraviolet wavelength range.

Space Environment Monitoring Instruments

  • Space Environment In-Situ Suite (SEISS) consists of four sensors:
    • Energetic Heavy Ion Sensor (EHIS) to measure the proton, electron, and alpha particle fluxes at geostationary orbit.
    • Magnetospheric Particle Sensor (MPS) is a magnetometer measuring the magnitude and direction of the Earth’s ambient magnetic field; and has two sensors the MPS-LO and MPS-HI.
    • Solar and Galactic Proton Sensor (SGPS) will, as the name indicates, measure the solar and galactic protons found in the Earth’s magnetosphere.
  • Magnetometer will measure of the space environment magnetic field that controls charged particle dynamics in the outer region of the magnetosphere.

The ABI instrument is the most interesting to us in terms of Earth observation, and it will produce a remarkable 25 individual products including Aerosol Detection, Cloud and Moisture Imagery, Cloud Optical Depth, Cloud Particle Size Distribution, Cloud Top Measurements, Derived Motion Winds & Stability Indices, Downward Shortwave Radiation at the Surface, Fire/Hot Spotting, Hurricane Intensity Estimation, Land Surface Temperature, Moisture & Vertical Temperature Profiles, Rainfall Rate, Reflected Shortwave Radiation at the Top Of Atmosphere, Sea Surface Temperature, Snow Cover, Total Precipitable Water and Volcanic Ash. If you want to look at the details of specific products then there are Algorithm Theoretical Basis Documents (ABTDs) available, which are like a detailed scientific paper, and can be found here.

The GOES-R is the first in a series of four satellites to provide NOAA with improved detection and observation of environmental events. It is not a cheap series of satellite, with the cost of developing, launching and operating this series estimated to be around $11 billion. However, this will provide observations up to 2036.

We’re excited by this launch, and are looking forward to being able to utilise some of this new generation weather information.

Monitoring ocean acidification from space

Enhanced pseudo-true colour composite of the United Kingdom showing coccolithophore blooms in light blue. Image acquired by MODIS-Aqua on 24th May 2016. Data courtesy of NASA.

Enhanced pseudo-true colour composite of the United Kingdom showing coccolithophore blooms in light blue. Image acquired by MODIS-Aqua on 24th May 2016. Data courtesy of NASA.

What is ocean acidification?
Since the industrial revolution the oceans have absorbed approximately 50% of the CO2 produced by human activities (The Royal Society, 2005). Scientists previously saw this oceanic absorption as advantageous, however ocean observations in recent decades have shown it has caused a profound change in the ocean chemistry – resulting in ocean acidification (OA); as CO2 dissolves into the oceans it forms carbonic acid, lowering the pH and moving the oceans into a more acidic state. According to the National Oceanic Atmospheric Administration (NOAA) ocean pH has already decreased by about 30% and some studies suggest that if no changes are made, by 2100, ocean pH will decrease by 150%.

Impacts of OA
It’s anticipated OA will impact many marine species. For example, it’s expected it will have a harmful effect on some calcifying species such as corals, oysters, crustaceans, and calcareous plankton e.g. coccolithophores.

OA can significantly reduce the ability of reef-building corals to produce their skeletons and can cause the dissolution of oyster’s and crustacean’s protective shells, making them more susceptible to predation and death. This in turn would affect the entire food web, the wider environment and would have many socio-economic impacts.

Calcifying phytoplankton, such as coccolithophores, are thought to be especially vulnerable to OA. They are the most abundant type of calcifying phytoplankton in the ocean, and are important for the global biogeochemical cycling of carbon and are the base of many marine food webs. It’s projected that OA may disrupt the formation and/or dissolution of coccolithophores, calcium carbonate (CaCO3) shells, impacting future populations. Thus, changes in their abundance due to OA could have far-reaching effects.

Unlike other phytoplankton, coccolithophores are highly effective light scatterers relative to their surroundings due to their production of highly reflective calcium carbonate plates. This allows them to be easily seen on satellite imagery. The figure at the top of this page shows multiple coccolithophore blooms, in light blue, off the coast of the United Kingdom on 24th March 2016.

Current OA monitoring methods
Presently, the monitoring of OA and its effects are predominantly carried out by in situ observations from ships and moorings using buoys and wave gliders for example. Although vital, in situ data is notoriously spatially sparse as it is difficult to take measurements in certain areas of the world, especially in hostile regions (e.g. Polar Oceans). On their own they do not provide a comprehensive and cost-effective way to monitor OA globally. Consequently, this has driven the development of satellite-based sensors.

How can OA be monitored from space?
Although it is difficult to directly monitor changes in ocean pH using remote sensing, satellites can measure sea surface temperature and salinity (SST & SSS) and surface chlorophyll-a, from which ocean pH can be estimated using empirical relationships derived from in situ data. Although surface measurements may not be representative of deeper biological processes, surface observations are important for OA because the change in pH occurs at the surface first.

In 2015 researchers at the University of Exeter, UK became the first scientists to use remote sensing to develop a worldwide map of the ocean’s acidity using satellite imagery from the European Space Agency’s Soil Moisture and Ocean Salinity (SMOS) satellite that was launched in 2009 and NASA’s Aquarius satellite that was launched in 2011; both are still currently in operation. Thermal mounted sensors on the satellites measure the SST while the microwave sensors measure SSS; there are also microwave SST sensors, but they have a coarse spatial resolution.

Future Opportunities – The Copernicus Program
The European Union’s Copernicus Programme is in the process of launching a series of satellites, known as Sentinel satellites, which will improve understanding of large scale global dynamics and climate change. Of all the Sentinel satellite types, Sentinels 2 and 3 are most appropriate for assessment of the marine carbonate system. The Sentinel-3 satellite was launched in February this year andwill be mainly focussing on ocean measurements, including SST, ocean colour and chlorophyll-a.

Overall, OA is a relatively new field of research, with most of the studies being conducted over the last decade. It’s certain that remote sensing will have an exciting and important role to play in the future monitoring of this issue and its effects on the marine environment.

Blog written by Charlie Leaman, BSc, University of Bath during work placement at Pixalytics.

British Science Won’t Be Eclipsed

Hawthorn leaves opening in Plymouth on 18th March 2015

Hawthorn leaves opening in Plymouth on 18th March 2015

We’re celebrating science in this blog, as it’s British Science Week in the UK! Despite its name British Science Week is actually a ten day programme celebrating science, technology, engineering, and maths (STEM). The week is co-ordinated by the British Science Association, a charity founded in 1831.

The British Science Association, like ourselves at Pixalytics, firmly believe that science should be at heart of society and culture and have the desire to inform, educate, and inspire people to get interested and involved in science. They promote their aims by supporting a variety of conferences, festivals, awards, training and encouraging young people to get involved in STEM subjects.

British Science week is one of their major annual festivals, and has hundreds of events running up and down the country. The website has a search facility, so you can see what events are running locally. Down here in Plymouth, the events include Ocean Science at The National Marine Aquarium, tomorrow at Museum & Art Gallery learn about the science behind the headlines and on Saturday, also at the Museum, an animal themed day including some real mini-beasts from Dartmoor Zoo – the place that inspired the 2011 film ‘We Bought A Zoo’, which starred Matt Damon and Scarlett Johnansson.

If you can’t get to any of the events in your local area, British Science Week is also promoting two citizen’s science projects:

  • Nature’s Calendar run by the Woodland Trust, asking everyone to look out for up to six common natural events to see how fast spring is arriving this year. They want to be informed of your first sightings of the orange tipped butterfly, the 7-spot ladybird, frog spawn, oak leaves, Hawthorn leaves, and Hawthorn flowers. This will continue a dataset which began in 1736, and we thought the Landsat archive was doing well.
  • Worm Watch Lab – A project to help scientists better understand how our brain works by observing the egg laying behaviour of nematode worms. You watch a 30 second video, and click a key if you see a worm lay an egg. We’ve watched a few and are yet to see the egg laying moment, but all the video watching is developing a lot of datasets for the scientists.

If you are interested in Citizen Science and go to sea, why not get involved in the citizen science work we support, by taking part in the Secchi Disk Project. Phytoplankton underpin the marine food chain and is particularly sensitive to changes in sea-surface temperatures, so this project aims to better understand their current global phytoplankton abundance. You do this by lowering a Secchi disk, a plain white disk attached to a tape measure, over the side of a boat and then recording the depth below the surface where it disappears from sight. This measurement is uploaded to the website and helps develop a global dataset of seawater clarity, which turn indicates the amount of phytoplankton at the sea surface. All the details on how to get involved are on the website.

On Friday, nature is getting involved by providing a partial solar eclipse over the UK. Starting at around 8.30am the moon will take about an hour to get to the maximum effect where the partial eclipse will be visible to the majority of the country – although the level of cloud will determine exactly what you see. Plymouth will be amongst the first places in the country to see the maximum effect around 9.23am – 9.25am, however the country’s best views will be on the Isle of Lewis in Scotland with a 98% eclipse predicted. The only two landmasses who will see a total eclipse will be the Faroe Islands and the Norwegian arctic archipelago of Svalbard. The last total eclipse in the UK was on the 24th August 1999, and the next one isn’t due until 23 September 2090!

Although the eclipse is a spectacular natural event, remember not to look directly at the sun, as this can damage your eyes. To view the eclipse wear a pair of special eclipse glasses, use a pinhole camera or watch it on the television!

We fully support British Science Week, it’s a great idea and we hope it will inspire more people to get involved in science.