Astrocast.TV

Author Archive

This week is World Water Week. The big event takes place in Stockholm Sweden where Stockholm International Water Institute SIWI is organizing this, since 1991, yearly event. This year the topic, besides the fact that it is all about water of course, is The Water Quality Challenge: Prevention, Wise Use and Abatement.

Access to clean water and proper sanitation is one of the 8 millenium goals. Better understanding of the water cycle is thus an important task for our global society, particularly in the developing countries. With increased urbanizations in areas where access to fresh water seems to be in peril makes events like World Water Week and research connected to better understanding of the water cycle an even high political and scientific priority. The overall niche for the current World Water Week period 2009-2012 is Water – Responding To Global Change.

Observing inland water from space
Earth observations from space have been used as a source of information about water for many years. We’ve seen satellite images of various floods on numerous occasions. The immense flood in Pakistan is particularly impressive in the many satellite images from both ESA and NASA satellites.

New space-based observation techniques are emerging though. ESA’s Soil Moisture and Ocean Salinity – SMOS has the potential of becoming an additional space-based technique to underpin our understanding – and warning of potentially hazards floods – by giving information about the degree of water saturation of the soil in the vicinity of rivers like Indus. If the soil is saturated with moisture at the point when rivers are flooding the uptake of water by surrounding soil will be limited.

SMOS and Pakistan flood:

In May I talked to one of the pioneers in the field of satellite altimetry and SMOS expert on retrieving information about soil moisture – professor Philippa Berry. You can watch and learn here:

or directly here:
The problem in Pakistan and right now is too much water, but the areas downstream from the Himalayas have also the opposite problem, namely too little water. This particular complex problem is discussed in a feasibility study ordered by The Norwegian Ministry of Foreign Affairs. It is a challenge for the people in the Hindu Kush-Himalayas to adapt to the increased climatic risk of severe floods and droughts.  Read the report  Too much – Too little Water: Adaptation to Climate Change in the Hindu Kush Himalayas and Central Asia.

With the help of another kind of satellite, GRACE, measuring variations in gravity, one is able to see that ground water is retracting from large areas in India. This vanishing of groundwater is mainly due to human activities like irrigation of cropland. Water management is clearly done better with the help of space based observations.

The International Geophysical Year (IGY) in 1957-1958 contributed to the kick-off of the space race and gave birth to space geodesy. Both rather remarkable achievements. The grand finale of the International Polar Year 2007-2008 is taking place in Norway at the IPY Oslo Science Conference, and I am looking for indicators of a similar spectacular overall result as the IGY legacy.

Again I am leaning towards the space segment, for a number of reasons not all of which are obvious. The obvious being the facts that I am producing A Green Space – A Green Earth and being an astrophysicist.

The conference program is divided into 6 themes covering the whole range of IPY activities.

Theme 1. Linkages between Polar Regions and global systems
Theme 2. Past, present and future changes in Polar Regions
Theme 3. Polar ecosystems and biodiversity
Theme 4. Human dimensions of change: Health, society and resources
Theme 5. New frontiers, data practices and directions in polar research
Theme 6. Polar science education, outreach and communication

In Theme 5. New frontiers, data practices and directions in polar research you find the contributions from satellites (Space for polar science) along other new observation networks and capacity developments as well as interdisciplinary state of the art polar science.

Satellites in IPY
The space agencies joined their polar forces under the IPY umbrella. In 2005 the Global Interagency IPY Polar Snapshot Year (GIIPSY) proposal was selected as an IPY flagship project. The goal of GIIPSY was to develop polar science requirements and objectives that could best and perhaps only be met using the international constellation of Earth observing satellites.

Mark Drinkwater from ESA presented the result of the interagency efforts during the IPY and I’ll come back to more details of that in a later report, but I will tell you what the future plans are.

Virtual Polar Satellite Constellation
The main goal of a future effort would be to continue the work of the so-called IPY Space Task Group who coordinated the work of space and cryosphere scientists during IPY. Our interest in the polar regions does not start or stop with international polar years, it is continuous need for coordination of international efforts in order to secure collections of space-borne “snapshots” of the polar regions. Mark Drinkwater concludes his talk by suggesting development of a virtual Polar Satellite Constellation.

The polar regions are far, far away for most people. Do not count me in among ‘most people’ though. As a Norwegian I practically live in the Arctic. There are only 8 nations that are (partly) situated in the Arctic: Canada, Denmark, Finland, Iceland, Norway, Sweden, Russia and USA  Several countries claim rights in Antarctica, which is regulated by the Antarctic Treaty . Sometimes we talk about a third pole, namely The Himalayas. Common for all three regions are remoteness and inaccessibility.

Polar exploration is deeply founded in the Norwegian identity, yet I have no difficulty understanding why people outside polar regions ask themselves What’s in it for me? How can we defend using so much resources and efforts on science constrained to these remote regions?

This week, the 4th* International Polar Year (2007-2008) will be summarized, analyzed and future follow-up plans developed at the biggest polar gathering ever: the IPY Oslo Science Conference.

At this point it is a bit early to say whether the results from the 2007-2008 IPY will be equally important as the last of this kind of scientific feast, the International Geophysical Year (IGY) in 1957-1958 turned out to be. IGY coincided with or marked the start of the space race and the birth of space geodesy. (Vanguard 2, see video), no small achievement on any scale or from any perspective, and can definitely be defended when it comes to the use of resources versus societal benefit.

I will be attending the IPY Oslo Science Conference keeping a keen eye on the space based polar science. For numerous reasons, there were very few satellites covering the arctic and antarctic regions. I will also look for examples of inter-disciplinary research and apply a special twist to the information. By the end of the conference I hope I will have answered the question What’s in it for YOU? through my daily reports and articles. If you are not satisfied with the reasons presented in the official IPY documents, that is.

* The former polar years where in 1882-83, 1932-33, 1957-58 (International Geophysical Year was modeled after the two previous polar years and included polar activities).

 

One single remotely situated volcano managed to close down the entire European air space for days. The volcano on Eyjafjallajökull in Iceland, the small country far north in the middle of the North-Atlantic, may have been known to volcanologists and other geoscientists with a keen interest in a geophysical hot spot like Iceland. But to the rest of us Eyjfjalljökull was unknown until the massive flight cancellations in Europe caused by its ash cloud. Today, Eyjafjalljökull is world famous – though pronouncing its name remains a mystery.

One who knew Eyjafjallajökull very well long before it erupted, is Dr. Kristin Vogfjord. Working as Research Director at the Icelandic Meteorological Office she led a European research project on volcanoes and her group’s contribution were monitoring and analysis of the seismic activity on Eyjafjallajökull. Kristin tells us how the volcanic eruption still managed to surprise her and how the ash is produced in A Green Space – A Green Earth’s volcano edition.

Earth observations from space are being used in all phases of volcanic eruptions; before, during and after. NASA scientists (Dr. Andrea Donnellan and Dr. Paul Lundgren) and leading experts on GPS and InSAR, two space based instruments and techniques applied in all three phases of an eruption, explain how they work and are being used. In particular you’ll learn how closely linked earthquakes and volcanic eruptions are. In fact, we illustrate the geophysical crème brûlée model using a genuine crème brûlée (a delicious French desert).

Eyjafjallajökull did disrupt our lives for days, but there were no casualties. When Mount St. Helens erupted 30 years ago, more than 50 persons lost their lives, including USGS volcanologist David A. Johnston on his observation post. USGS is commemorating Mount St. Helens devastating reawakening on May 18th 1980 with a series of events this summer and fall. We show some of the unique materials made available by USGS and explain why it was so lethal.

Seemingly there is nothing but trouble with these volcanoes. In fact, we can turn it completely around and say there wouldn’t be life on this planet without them. Volcanoes contribute in several ways to keep the Earth system in balance and A Green Space – A Green Earth’s Volcano edition gives you a few examples of how.

Finally, if you would like to impress your friends and colleagues by learning how to pronounce Eyjafjallajökull, you can watch this episode over and over again because I say Eyjafjalljökull, like the Icelandic, numerous times. This information might perhaps assist you in your efforts: Eyja=island, fjalla=mountain and jökull=glacier. Good luck!

The limited amount of water on this planet is recycled in what we simply call the water cycle. Chasing water’s whereabouts in this cycle is complicated. Space techniques provide us with an increased number of observations of water in the various elements of the water cycle.

In the ‘Chasing Water’ episode of A Green Space – A Green Earth we focus on a technique that has been operational for 17 years now, namely satellite altimetry.

Currently the satellite Jason-2 is orbiting Earth, measuring sea surface height. Ocean observations was the original motive for these types of missions, but they have turned out to be more useful than first anticipated. Satellite altimetry is now also being used for monitoring inland waters such as rivers and lakes, and thus other elements of the water cycle.

Meet veteran altimetry expert Dr Ole Andersen and pioneer professor Philippa Berry and hear them talk about satellite altimetry and how it is being used today.

Fresh water will become more scarce in years to come. That includes highly populated areas, such as California in the USA. Deforestation is still a serious problem in developing countries. Chasing water with satellites is and will continue to be of great importance to our society.

Further reading:

ESA on water cycle
Jason-2
Mean Sea Level data from satellite altimetry

Satellite altimetry tracks rivers

A Green Space – A Green Earth was launched on Earth Day 2009 and thus celebrates our 1 year anniversary. We are of course young compared to Earth Day it self who in 2010 celebrates its 40th anniversary.

A Green Space – A Green Earth started out with a story about the long awaited launching of ESA’s GOCE satellite. The resulting increased knowledge about the geoid – a geophysical reference for height measurements – will contribute to and complement satellite altimetry, yet another geodetic satellite we focus on in our May episode called Chasing Water. After 17 years of continuous operation of satellite altimeters measuring sea surface height, we have developed the technique to measure inland water lakes and land topography. You’ll meet altimeter veteran Dr. Ole B Andersen from the National Danish Space Centre and pioneer in alternative use of satellite altimeters Professor Philippa Berry from Uk’s De Monfort University.

The planet will certainly not be green without water!

Climategate: To Share Or Not To Share

Climategate or no climategate? Availability of climate data is one element of the so-called Climategate, the hacker incident at East Anglia University in the UK that revealed parts of an email communication among a group of international climate scientists. The fundamental factor for the science in this case, is the question of whether the data, the facts concerning climate, is correct or not. The scientific community outside the East Anglia group, wanted access to the data upon which the research was based. In this episode of A Green Space – A Green Earth I focus on data sharing: To share or not to share. Are there any obstacles?

Open data policy is fundamental for modern research. Scientific communities are global and we need global earth observation data to understand the Earth system. If we look beyond the data, and analyze the scientific work method (not scientific method; that is timeless and independent of context), the modern, more open society, demands more of the scientific communities.

Links and further reading:

Essential Climate Variables

Nature (magazine) on climate data theft and pressure on scientists

Summary from GEO in DC (Earthzine)

The IPCC Science report

Anthroposphere

From BBC: ‘Show Your Working’: What ‘ClimateGate’ means. By Mike Hulme East Anglia University and Dr Jerome Ravetz

ESA open data policy.

Sentinels: ESA and EC data policy implementation strategy.

“ESA has developed the Climate Change Initiative to generate, preserve and give access to long-term data sets of the essential climate variables and make them freely available to climate research and modelling communities worldwide,”

Group on Earth Observations – GEO

Climategate: To share Or Not To Share will be updated..

 

The Science Behind The Haiti Earthquake.

We take a closer look at the science behind the Haiti earthquake of 12th January 2009 – as well as other earthquakes. For the first time here on GSGE we interview leading experts;

Prof. Timothy Dixon from Geodesy Lab at University of Miami: published an article already back in 1998 revealing the risks of earthquakes in Haiti. He works with both Paul Mann from University of Texas who in 2008 confirmed that the risks were eminent, and Eric Calais, Purdue University who manages the GPS network that monitor tectonic plate movements in Haiti. These three groups have sent geodesists with GPS equipment, to Haiti where they gather data that will reveal the crustal movements caused by the quake. You can follow this National Science Foundation funded team via their blog.

Ass. Prof. William Hammond from University of Nevada in Reno: Explains how they use GPS to monitor plate movements – and earthquake swarms. Bill Hammond also appears in National Geographic’s Naked Science: Earthquake Swarms.

Dr. Amir Kaynia from the International Centre for Geohazards in Oslo, Norway: Talks about the difference between predictions and early warning and discuss other geohazards connected to earthquakes.

Read more about the early warning and mitigation aspects in The Haiti Earthquake: Science, early warning and mitigation.

Some useful and informative links:

National Science Foundation’s GPS team blog from Haiti:

GEO’s Haiti Supersite. Collection of Haiti earthquake science information.

Eric Calais’s Haiti site. (responsible for the tectonic plate movements Haitian GPS network together with local Haitian authorities).

Haiti Earthquake at University of Miami

Haiti Earthquake at University of Texas.

The International Centre for Geohazards:

The Global Geodetic Observing System (GPS is a space-based geodetic technique. Provision of global GPS data is one of the services of Global Geodetic Observing System)

Climate change and sea level forecasting is the topic of A Green Space – A Green Earth in July.
Sea level forecasting relies on both Earth observation from space as well as data from coastal tide gauges. Climate change makes sea level estimates in the future very uncertain. What we need are sea level forecasts equivalent to weather forecasts.

The world is populated in a growing number of mega cities, cities with more than 1 million inhabitants, and people are migrating towards the coastal areas, making inhabitants in general, more vulnerable to natural hazards like sea level rise, storm surges and tsunamis.

Coastal megacities – cities with more than 1 million inhabitants situated within 100 km of the coast line. Cartographer: Hugo Ahlenius, Nordpil

Sea level forecasting, similar to weather forecasting, would improve our ability to adapt to changes in sea level caused by global warming. Sea level does change on a regular basis, whose variations are very predictable, caused by the Moon, the Sun and the planets, resulting in the well known tides.

The Earth and it’s moon. Credit: JAXA

We rely on Earth observation from space for sea level forecasts, and current sea level monitoring.
In the July 2009 episode of A Green Space – A Green Earth, an acknowledged sea level expert, Professor Hans-Peter Plag from University of Nevada, Reno, USA comments on the challenges related to climate change and sea level. Earth observation from space is absolutely pivotal for managing sea level change, says professor Plag, who also works on analysis of continuous coastal tide gauge recordings of sea level. In addition to the tide gauges itself, we need GPS on, or as close to, the tide gauges as possible, in order to achieve the highest accuracy of sea level measurements. It is a combination of space and ground based Earth observations that will enable us to produce sea level forecasting. A number of countries contribute their national sea level data from tide gauges to the Global Sea Level Observing System – GLOSS.

Prof. Hans-Peter Plag inspecting a tide gauge in Venice, Italy. Notice the GPS receiver on top of the tide gauge house. Image courtesy of William Hammond.

Sea level change depends on the location; that is, where on the planet you are, the local topography and bathymetry etc. Sea level change will have an impact on a large variety of cultural and geographical landscapes. We’ve chosen a few places on our planet that illustrate different experiences and aspects of sea level variations and adaptation strategies.

New York, Jakarta, London and Rotterdam are global megacities. They are all large economic centers and are collectively addressing the challenges of managing the uncertainty inherent in climate change and various sea level scenarios.

Manhattan as seen from space. Credit: NASA

Bustling New York City harbor – as seen from the water level. Credit: NJ Photographer

Venice, Italy, representative of those locations that we treasure for their cultural heritage and historic value. Venice is already a UNESCO world heritage site and has been working on strategies of adaptation to rising sea level, particularly since the whole city has already been subsiding for 1000 years.

The new Opera house in Oslo, Norway is situated on one of the best locations in Norway with respect to future sea level rise – the uplift of land (post glacial rebound) will compensate for sea level rise for a long time. Norwegians, modern times’ Vikings, are making a living from fishing, oil and shipping which are the main national income sources. Monitoring sea level, and adaptation to climate change, is just as much an economic issue it is as an environmental issue for the average Norwegian.

The Opera in Oslo. Credit: Renny Bakke Amundsen

Geodesists from the Norwegian Mapping Authority inside the Oslo Opera ready to survey the height relative to sea level of the Oslo harbor. Credit: Bjørn-Geirr Harsson

Bangladesh is one of the poorest and most densely populated countries in the world and it will suffer tremendously from sea level rise.

With a sea level rise of one meter, one seventh of Bangladesh will be covered by the sea. Credit: NASA

In June 2008, the tiny South Pacific nation of Kiribati announced that rising sea levels were making its lands uninhabitable and asked for help in evacuating its population. As we could read in the New York Times in May 2009, the President of the Maldives, an island in the Pacific, has asked the population to start saving money for buying a new country as the island nation will be completely devoured by the rising sea and the evacuation of the whole population of 300,000 is the only option for survival. Clearly he would be in favor of sea level forecasting.

Kiribati as seen from space. Credit: NASA

The Maldives as seen from space. Credit: NASA

Watch the July 2009 episode of A Green Space – A Green Earth.

Further readings related to climate change, sea level and sea level forecasting:

Intergovernmental Panel on Climate Change

ESA’s Earth Explorers

NASA’s Eyes on The Earth

Climate Variability and Change

Climate Resilient Cities

Impact of sea level rise in Bangladesh

The Maldives and Rising Sea Level

Sea Level at Kiribati

A special thanks to cartographer Hugo Ahlenius at Nordpil who tailor made a map of coastal mega cities. He has done a lot of excellent work for UNEP and we are grateful that he on very short notice created yet another beautiful map, this time for Astrocast.TV covering climate change and sea level forecasting.

This month A Green Space – A Green Earth focus on disaster mitigation and early warnings and how space based Earth observations contributes to safe-guard lives and property.

New satellite techniques such as InSAR complement GPS in unraveling in fine details crustal movements of the Earth. ESA’s GOCE gravity measurements from space will add knowledge to our understanding of sub-surface movements leading up to earthquakes. Through observing Earth from space before, during and after earthquakes we improve disaster mitigation and early warnings.

Learn more about earthquakes and the examples mentioned in this episode through the following links:

How does InSAR work?

InSAR used at the L’Aquila, Italy earthquake 2009.

Seismic and Medical Tomography

Global Earthquake Model – A OECD program

Indian Ocean Tsunami Disaster 2004 – A portal for more information at University of Buffalo, NY, USA

Wenchuan, China earthquake 2008 – A portal for maps and geophysical information about the earthquake

Wenchuan, China earthquake 2008 in numbers (in Chinese with map from China Earthquake Adminstration)

L’Aquila, Italy earthquake 2009 in pictures – A collection of images in Boston Globe.

Space geodetic techniques – A portal for more information about space based geodetic techniques

.