News From Space: MAVEN Launched

maven_launchYesterday, NASA’s Mars Atmosphere and Volatile Evolution (MAVEN) space probe was finally launched into space. The flawless launch took place from Cape Canaveral Air Force Station’s Space Launch Complex 41 at 1:28 p.m. EST atop a powerful Atlas V rocket. This historic event, which was the culmination of years worth of research, was made all the more significant due to the fact that it was nearly scrapped.

Back in late September, during the government shutdown, NASA saw its funding curtailed and put on hold. As a result, there were fears that MAVEN would miss its crucial launch window this November. Luckily, after two days of complete work stoppage, technicians working on the orbiter were granted an exemption and went back to prepping the probe for launch.

NASA_mavenThanks to their efforts, the launch went off without a hitch. 52 minutes later, the $671 Million MAVEN probe separated from the Atlas Centaur upper stage module, unfurled its wing-like solar panels, and began making its 10 month interplanetary voyage that will take it to Mars. Once it arrives, it will begin conducting atmospheric tests that will answer key questions about the evolution of Mars and its potential for supporting life.

Originally described as a “time-machine for Mars”, MAVEN was designed to orbit Mars and examine whether the atmosphere could also have provided life support, what the atmosphere was like, and what led to its destruction. This mission was largely inspired by recent discoveries made by the Opportunity and Curiosity rovers, whose surface studies revealed that Mars boasted an atmosphere some billions of years ago.

maven_atmo1During a post launch briefing for reporters, Bruce Jakosky – MAVEN’s Principal Investigator – described MAVEN’s mission as follows:

We want to determine what were the drivers of that change? What is the history of Martian habitability, climate change and the potential for life?

Once the probe arrives in orbit around Mars, scheduled for September 22nd, 2014, MAVEN will study Mars’ upper atmosphere to explore how the Red Planet may have lost its atmosphere over the course of billions of years. This will be done by measuring the current rates of atmospheric loss to determine how and when Mars lost its atmosphere and water.

maven_atmosphereFor the sake of this research, MAVEN was equipped with nine sensors the come in three instrument suites. The first is the Particles and Fields Package – which contains six instruments to characterize the solar wind and the ionosphere of Mars – that was provided by the University of California at Berkeley with support from CU/LASP and NASA’s Goddard Space Flight Center.

The second suite is the Remote Sensing Package, which ill determine global characteristics of the upper atmosphere and ionosphere and was built by CU/LASP. And last, but not least, is the Neutral Gas and Ion Mass Spectrometer, built by Goddard, which will measure the composition of Mars’ upper atmosphere.

As for the long term benefits of the mission and what it could mean for humanity, I’d say that Dr. Jim Green – NASA’s Director of Planetary Science at NASA HQ in Washington, DC – said it best:

We need to know everything we can before we can send people to Mars. MAVEN is a key step along the way. And the team did it under budget! It is so exciting!

Source: universetoday.com

Climate Crisis: The Pacific Ocean’s Cooling Effect

pacific1Climatologists and environmental scientists have been cataloging the global warming trend for decades, examining multiple fields of data that show fluctuations over a period of eons. And despite what appears to be a consistent trend warming that has been taking place since the 18th century – when levels of atmospheric CO2 began to climb steadily – there have been anomalies in the data.

One period was the three decades that fall between the 1940’s and 1970’s when no significant terrestrial warming took place, and the Pacific Ocean was anomalously cold. The Pacific is somewhat of a wild card when it comes to our climate, since it is responsible for the weather patterns known as El Niño and La Niña that can swing global average temperatures by as much as 0.3 degree Celsius.

Global_Temperature_Anomaly_1880-2012.svgFor the past decade or so the tropical Pacific has again gone cold and a new study suggests that it may once again be related to the recent “pause” in global warming of average temperatures. Although the past decade also qualifies as the hottest on record, the trend has been milder than expected, with average surface temperatures plateauing for many years.

This is in stark contrast to the end of the 20th century, when rising concentrations of greenhouse gases in the atmosphere accelerated warming to new heights. To explain this, climate scientists Shang-Ping Xie and Yu Kosaka of the Scripps Institution of Oceanography at the University of California looked to the Pacific Ocean, using observable data and an advanced computer model.

NASA_global_warming_predThe latter came from the US Department of Commerce’s Geophysical Fluid Dynamics Laboratory computer model of the oceans and atmosphere. By adding in sea-surface temperatures of an oceanic area covering roughly 8 percent of the globe, the researchers were able to mimic the recent hiatus in global warming as well as weather phenomena like the prolonged drought in the southern US.

The results were published in the Aug. 29th edition of Nature Magazine. In it, Xie observed that the “tropical Pacific is the engine that drives the global atmosphere and climate. There were epochs of accelerated and stalled warming in the past.” This included the pause in a global warming trend between the 1940s and 1970s, which has often been attributed to sunlight-blocking air pollution from Europe, the Soviet Union and the US.

Pollution over Mexico CityOther factors have also been considered – volcanoes, an unusually weak solar cycle, air pollution from China – when looking at restraining trends in global warming. Some of the observed climate effects may also stem from other ocean dynamics such as variations in the mixing of surface and deep ocean waters. And the meltdown of significant ice from Greenland or Antarctica might even cool oceans enough to offset the extra heat trapped by rising levels of greenhouse gases for a time.

What is less clear at this point is what is driving cycles of cooling and heating of tropical Pacific Ocean waters. But it is clear that the cool Pacific pattern cannot persist forever to cancel out the extra heat trapped by rising CO2 concentrations, Xie notes. As climate modeler Gavin Schmidt of the NASA Goddard Institute for Space Studies recently stated:

We need updates to the forcings and a proper exploration of all the different mechanisms together. This has taken time but will happen soon-ish.

global-warming-trends_lrgAnd despite any pause in the trend toward hotter temperatures, the first decade of the 21st century was still the hottest recorded decade since the 1880s, and it included record heat waves in Russia and the US as well as a precipitous meltdown of Arctic sea ice and surging sea level rise. Atmospheric concentrations of CO2 touched 400 parts per million on Mauna Loa in May, a first in the time line of human existence.

A cooler Pacific due to prolonged La Niña activity may have restrained global warming for the past decade or so, but it is unlikely to last. As Xie noted:

This effect of natural variability will be averaged out over a period of 100 years. and cannot argue away the threat of persistent anthropogenic warming that is occurring now.

These warnings are key since any changes or anomalous readings are often seized upon by Climate Change deniers as evidence that the problem does not exist, is not man-made, or is at least not as severe as otherwise predicted. But in the coming decades, even the most benign scenarios are still fraught with peril. If the worst is to be averted, extensive and positive changes need to be made now.

Source: news.cnet.com, nature.com