any other marine environment. This implies that the ecosystem functioning that produces the most highly valued components is also complex and that many otherwise insignificant species have strong effects on sustaining the rest of the reef system. 860 Thus, maintaining and restoring the biodiversity of marine ecosystems is critical to maintaining and restoring the ecosystem services that they provide. Non-use biodiversity values for marine ecosystems have been calculated in the wake of marine disasters, like the Exxon Valdez oil spill in Alaska. 861 Similar calculations could derive preservation values for marine wilderness. However, economic value, or economic value equivalents, should not be "the sole or even primary justification for conservation of ocean ecosystems. Ethical arguments also have considerable force and merit." 862 At the forefront of such arguments should be a recognition of how little we know about the sea - and about the actual effect of human activities on marine ecosystems. The United States has traditionally failed to protect marine ecosystems because it was difficult to detect anthropogenic harm to the oceans, but we now know that such harm is occurring - even though we are not completely sure about causation or about how to fix every problem. Ecosystems like the NWHI coral reef ecosystem should inspire lawmakers and policymakers to admit that most of the time we really do not know what we are doing to the sea and hence should be preserving marine wilderness whenever we can - especially when the United States has within its territory relatively pristine marine ecosystems that may be unique in the world. We may not know much about the sea, but we do know this much: if we kill the ocean we kill ourselves, and we will take most of the biosphere with us. The Black Sea is almost dead, 863 its once-complex and productive ecosystem almost entirely replaced by a monoculture of comb jellies, "starving out fish and dolphins, emptying fishermen's nets, and converting the web of life into brainless, wraith-like blobs of jelly." 864 More importantly, the Black Sea is not necessarily unique.
No working PHO deflection method in the status quo.
Bradley et al 2010 [P. A.; Plesko, C. S.; Clement, R. R. C.; Conlon, L. M.; Weaver, R. P.; Guzik, J. A.; Pritchett-Sheats, L. A.; Huebner, W. F.; American Institute of Physics Conference Proceedings; 1/28/2010, Vol. 1208 Issue 1, p430-437, Los Alamos National Laboratory, PN] [PHO - potentially hazardous object]
In this paper, we describe the threat posed PHOs and mention how they are different from other natural disasters in two important respects. First, a large enough (greater than 1-km diameter) object has the potential to destroy civilization. At 10 km, a PHO would be roughly the size of the K/T impactor and would cause mass extinctions, including possibly that of humanity itself. Unlike other natural disasters where at best we can evacuate an affected area and deal with the damage afterwards, humanity has the potential to deflect a PHO before it collides with the Earth. There are many ways possible to accomplish this mitigation, but we feel that chemical explosives, kinetic energy impactors, and nuclear munitions are the only technologies that are readily available for the near term. Of these, we focus on nuclear munitions because they offer the most concentrated source of energy per unit mass. We must emphasize that deflection is our preferred option because we cannot reliably predict the fragmentation and dispersal of an asteroid.
We also describe our technical work on the possibility of using nuclear munitions for deflecting an asteroid or comet nucleus on a collision course with Earth. Our calculations of nuclear bursts with energies of 10, 100, and 1000 kt on spheres 100 m in diameter show that we can impart impulses of up over 500 cm/s. We also show that the composition of the target and distance of the burst from the target have considerable impact on the final center of mass velocity. However, these calculations do not yet include the material strength of the body, porosity, fractures, or irregularly shaped objects. We are starting to run calculations that use the shape of asteroid 25143 Itokawa as an example of an irregularly shaped object. Much work remains to be done and the ultimate goal of our project is to create a catalog of deflection simulations where we vary the distance, magnitude, and targeting of the burst from PHOs of different sizes, shapes, internal structure, and compositions (Huebner et al., 2009). This catalog would provide a playbook that decision-makers can use to guide the range of possible responses to a given PHO threat.
Asteroid detection methods fail in multiple areas of the Status Quo.
Bradley et al 2010 [P. A.; Plesko, C. S.; Clement, R. R. C.; Conlon, L. M.; Weaver, R. P.; Guzik, J. A.; Pritchett-Sheats, L. A.; Huebner, W. F.; American Institute of Physics Conference Proceedings; 1/28/2010, Vol. 1208 Issue 1, p430-437, Los Alamos National Laboratory, PN]
Although we have come a long ways since the Tunguska event of June 30, 1908, there is still much we do not know. Even when finished, planned surveys will still not be complete for objects smaller than 140 meters. Such an asteroid or comet nucleus would be large enough to wipe out an area from New York City to Washington, D.C. Objects smaller than about 140 meters will be difficult to detect with much advance warning simply because they are extremely faint except when they are close to Earth. Although we sent probes to several asteroids and comets, we only have detailed information for a few. We also do not have detailed knowledge of the internal structure of asteroids, especially ones of order 10 to 1000 meters in diameter. An asteroid’s response to an impulsive energy burst --- whether it be high explosives, kinetic energy impactor, or nuclear burst --- will be sensitive to both the composition (ice, rock, rock/ice, or iron) and structure (monolithic piece, fractured, or rubble pile) of the body. While we may be able to determine at least the surface composition of a PHO in advance, we may not be able to determine the internal structure in advance. Any mitigation strategy must account for this uncertainty.