LDEO Seismology: Long-Period Noise

T24A-TA , LHE

Noise Levels at Different Periods

The table below gives the decibel 10% noise level (in db) for each month in several period bands. The 10% noise level is defined as the signal level not exceeded 10% of the time, based on hourly measurements. Each entry in the table is color coded with reference to the New Low Noise Model (NLNM, Peterson, 1993):
navy, -6 db < value-NLNM < -3 db
blue, -3 db < value-NLNM < 3 db
aqua, 3 db < value-NLNM < 6 db
lime, 6 db < value-NLNM < 9 db
yellow, 9 db < value-NLNM < 12 db
orange, 12 db < value-NLNM < 15 db
red, 15 db < value-NLNM < 20 db
fuchsia, 20 db < value-NLNM < 25 db
silver, value-NLNM < -6 db, value-NLNM > 25 db

Black indicates that there was an insufficient number of hourly measurements to calculate a noise level.

Noise levels (PSD) in decibels
Month Chan. Qual. # obs. 268s 228s 193s 164s 139s 118s 100s 85s 72s 61s 52s 44s 37s 32s 27s 23s 19s 16s 14s 12s 10s

200908 LHE AR 247 -126 -128 -129 -131 -132 -134 -136 -138 -140 -142 -144 -146 -148 -148 -151 -152 -152 -153 -154 -156 -155

200905 LHE AR 641 -126 -128 -129 -132 -134 -136 -138 -140 -141 -143 -145 -146 -149 -150 -152 -153 -154 -154 -154 -156 -153

200904 LHE AR 694 -130 -132 -134 -135 -138 -140 -142 -144 -147 -148 -150 -151 -153 -155 -155 -156 -156 -154 -154 -154 -150

200903 LHE AR 730 -129 -130 -132 -134 -136 -138 -139 -141 -143 -145 -146 -148 -150 -151 -152 -153 -154 -152 -152 -152 -149

200902 LHE AR 672 -126 -127 -129 -131 -133 -135 -137 -139 -141 -143 -145 -146 -148 -150 -152 -153 -154 -152 -151 -151 -148

200901 LHE AR 743 -127 -130 -132 -134 -136 -137 -139 -141 -143 -145 -147 -148 -150 -152 -153 -154 -154 -151 -151 -150 -149

200812 LHE AR 744 -124 -126 -129 -131 -133 -135 -136 -138 -140 -142 -143 -145 -147 -149 -150 -152 -152 -151 -150 -150 -149

200811 LHE AR 720 -127 -129 -131 -133 -134 -136 -137 -139 -141 -143 -145 -146 -148 -149 -151 -152 -153 -152 -151 -150 -150

200810 LHE AR 743 -125 -127 -129 -131 -133 -135 -136 -138 -139 -141 -142 -144 -146 -147 -149 -150 -151 -150 -150 -150 -149

200809 LHE AR 695 -124 -125 -127 -129 -130 -132 -133 -135 -137 -138 -140 -142 -143 -145 -146 -148 -149 -150 -150 -151 -150

200808 LHE AR 132 -124 -126 -127 -128 -130 -132 -133 -135 -137 -138 -140 -140 -143 -144 -145 -146 -148 -149 -150 -150 -150

200807 LHE AR 29 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999 999

Month	Chan.	Qual.	# obs.	268s	228s	193s	164s	139s	118s	100s	85s	72s	61s	52s	44s	37s	32s	27s	23s	19s	16s	14s	12s	10s
200908	LHE	AR	247	-126	-128	-129	-131	-132	-134	-136	-138	-140	-142	-144	-146	-148	-148	-151	-152	-152	-153	-154	-156	-155
200905	LHE	AR	641	-126	-128	-129	-132	-134	-136	-138	-140	-141	-143	-145	-146	-149	-150	-152	-153	-154	-154	-154	-156	-153
200904	LHE	AR	694	-130	-132	-134	-135	-138	-140	-142	-144	-147	-148	-150	-151	-153	-155	-155	-156	-156	-154	-154	-154	-150
200903	LHE	AR	730	-129	-130	-132	-134	-136	-138	-139	-141	-143	-145	-146	-148	-150	-151	-152	-153	-154	-152	-152	-152	-149
200902	LHE	AR	672	-126	-127	-129	-131	-133	-135	-137	-139	-141	-143	-145	-146	-148	-150	-152	-153	-154	-152	-151	-151	-148
200901	LHE	AR	743	-127	-130	-132	-134	-136	-137	-139	-141	-143	-145	-147	-148	-150	-152	-153	-154	-154	-151	-151	-150	-149
200812	LHE	AR	744	-124	-126	-129	-131	-133	-135	-136	-138	-140	-142	-143	-145	-147	-149	-150	-152	-152	-151	-150	-150	-149
200811	LHE	AR	720	-127	-129	-131	-133	-134	-136	-137	-139	-141	-143	-145	-146	-148	-149	-151	-152	-153	-152	-151	-150	-150
200810	LHE	AR	743	-125	-127	-129	-131	-133	-135	-136	-138	-139	-141	-142	-144	-146	-147	-149	-150	-151	-150	-150	-150	-149
200809	LHE	AR	695	-124	-125	-127	-129	-130	-132	-133	-135	-137	-138	-140	-142	-143	-145	-146	-148	-149	-150	-150	-151	-150
200808	LHE	AR	132	-124	-126	-127	-128	-130	-132	-133	-135	-137	-138	-140	-140	-143	-144	-145	-146	-148	-149	-150	-150	-150
200807	LHE	AR	29	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999	999